Crandell Pest Control – Pest Identifier Library
Not sure what that creepy crawly is in your home? Use our handy pest library to identify over 50 kinds of pests. Still have questions? That’s what we’re here for! Contact us today.
Introduction to Odorous Ants
The pungent, “rotten-coconutlike” odor given off when this ant is crushed gives it its name. It is a native species and is found throughout the United States. It is a major structural-invading species in the mid-Atlantic states, and in the mid-western and mid-southern regions.
Recognition of Odorous Ants
Workers monomorphic, about 1/16-1/8″ (2.4-3.3 mm) long. Body brown to black. Antenna 12-segmented, without a club. Thorax lacks spines, profile unevenly rounded. Pedicel 1-segmented, with small node/segment hidden/concealed from view from above by base of gaster. Gaster with anal opening slitlike, lacking circlet of hairs. Stinger absent. Workers emit a disagreeable, rotten, coconut-like odor.
Similar Groups to Odorous Ants
(1) Ghost ant (Tapinoma melanocephalum) with head and thorax dark but abdomen and legs pale.
(2) Whitefooted ant (Technomyrmex albipes) with tarsi pale yellowish-white
(3) Argentine (Linepitherma humilis), crazy (Paratrechina longicornis), pyramid (Conomyrma insana), and dark field (Formica spp.) ants have node visible, not hidden by gaster; in addition, pyramid ants with thorax with pyramidlike projection on upper surface towards rear, field and crazy ants with circular anal opening surrounded by circlet of hairs and crazy ants additionally with antennal scape (1st segment) at least twice head length and very long legs in relation to body size.
(4) Other small dark ants have 2-segmented pedicel and/or lack rotten coconut odor when crushed.
Biology of Odorous Ants
Colonies may be composed of several hundred to 100,000 ants, but usually number about 2,000 to 10,000 ants. There are usually many queens in a colony. Field-collected summer colonies in Tennessee were composed of about 150 workers to each queen and 200 workers for every square centimeter (0.155 square inches) of brood. Developmental time (egg to adult) is 34-83 days, varying with temperature during summer months, and up to 6-7 months during the winter. Colonies typically produce 4-5 generations a year. Although they mate both inside and outside the nest, the first swarmers appear from May to mid-July. Colonies can be founded by inseminated females or by budding. The workers and queens live for several years. Individuals from different colonies are not hostile to one another and workers normally move along trails.
Habits of Odorous Ants
Inside, these ants usually construct their nests near a moisture source such as in wall voids especially around hot water pipes and heaters, in bathtraps, beneath commodes with leaking seals, in crevices around sinks, cupboards, etc., but also in wood damaged by termites. These ants prefer sweets but also eat foods with high protein content and grease such as meats and cheese.
Outside, they are often found in the nest of larger ants, in exposed soil, but mostly under objects including stacks of lumber, firewood, bricks, etc. They have been found nesting in honey bee hives beneath the top and inner cover. Workers feed on live and dead insects, seek honeydew and plant secretions, and even feed on seeds. They are extremely fond of honeydew and attend such honeydew-excreting insects as plantlice (aphids), scale insects, mealybugs, etc. They are most likely to enter buildings when their honeydew supply is reduced such as during rainy weather or with leaf fall in the autumn. They forage during the day and at night when the temperature is 43-95°F (23-35°C). Like most ants, they follow guidelines or edges. They tend to move their nests every 3 months or so, often in response to rain.
When workers are alarmed, they run around in an erratic manner with their gasters/abdomens raised up.
Pest Control of Odorous Ants
Control is a 4-step process. First, location of the nest(s) is crucial and can often be accomplished by following the trail of foraging workers back from the food source. Treat the nest(s) directly with an appropriately labeled pesticide.
Second, a thorough perimeter treatment of a nonrepellent pesticide is highly effective in eliminating the ant problem; be sure to treat up under the bottom siding-to-foundation wall junction if present. In addition, all branches of trees and shrubs in contact with the building must be trimmed back. Be sure to check where electrical and water lines enter the building and caulk any gaps.
Third, on the inside, lightly mist/spritz any foraging trails of ants with a nonrepellent pesticide. This will speed up the control process. This outside-inside combo treatment will usually give results is a few days at most. Be sure to cover any surfaces below the application site with plastic before application to avoid unwanted contamination.
Fourth, baiting on the outside just beyond the treated area with a sucrose-based liquid bait will intercept the ants before they enter and give greater control for a longer period of time. This works best if inside sources of moisture and food are eliminated first.
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What does an Odorous House Ant look like?
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Introduction to Argentine Ants
This species, which is native to Argentina, Brazil, and Uraguay, was probably introduced at New Orleans via coffee ships from Brazil in the late 1800’s. Argentine ants are well established in the southern states, in California, and Hawaii. Less widespread infestations are found in Arizona, Missouri, Illinois, Indiana, Maryland, Missouri, Oregon, and Washington.
Recognition of Argentine Ant
Workers monomorphic, about 1/16″ (2.2-2.86 mm) long; queens about 1/8-1/4″ (4-6 mm), winged males about 1/16″ (2.8-3.0 mm) in length. Body varies from light to dark brown. Antenna 12-segmented, without a club. Thorax lacks spines, profile unevenly rounded. Pedicel 1-segmented. Gaster with anal opening slitlike, lacking circlet of hairs. Stinger absent, but can bite on provocation. Workers emit a stale greasy or musty odor when crushed.
Similar Groups to Argentine Ants
(1) Odorous house ant (Tapinoma sessile) has pedicel/node nearly hidden by front edge of abdomen/gaster, emit a sweetish rotten coconut odor when crushed.
(2) Crazy ant (Paratrechina longicornis) with legs very long in relation to body size, antennal scape (1st segment) at least 2 times head length, anal opening circular, surrounded by circlet of hairs.
(3) Other small dark ants with 2 nodes/segments in pedicel and/or thorax with 1 or more spines/teeth on upper surface.
Biology of Argentine Ants
Colonies are located in moist situations near a food source. They include a few hundred to several hundred thousand workers and many queens; typically about 10% queens and 90% workers. Their numbers fluctuate seasonally with a large build-up starting in the early spring. In the autumn, there is a huge die-off of workers and colonies sometimes join together to form massive overwintering supercolonies, which then break up into smaller colonies that disperse the following spring. Development time (egg to adult) is 33-141 days, averaging 74 days. Winged female reproductives are rarely seen because mating takes place inside the nest. Sometimes winged males will swarm to other nests for mating. The workers are very aggressive and usually eliminate other ant species and some other insects from the area. However, ants from different, but related, Argentine ant colonies are friendly and do not fight. Such a supercolony consisting of billions of ants was found to occupy an area extending about 3,600 miles (5793 km) in southeastern Europe.
Habits of Argentine Ants
Inside, these ants usually nest near a moisture source such as water pipes, sinks, potted plants, etc. The workers follow regular trails when foraging, and winged queens can sometimes be found among trailing workers. Workers commonly tend honeydew-producing insects. The preferred staple foods are sucrose-containing sweets such as honeydew, but they increase their intake of protein-containing foods such as prey during the spring and summer.
Outside, Argentine ants typically live in shallow nests about 8″ (20 cm) deep that are located in moist situations such as under boards and stones, beneath plants, along sidewalks, etc. This ant prefers sweets such as honeydew, fruit juices, and plant secretions, but also steals seeds,attacks poultry chicks, disrupts bee hives, etc.; in dry soil, nests can be as deep as 24″ (60 cm). Although they usually nest near their food source, they will forage for almost 200 feet (60 m). This ant prefers sweets such as honeydew, fruit juices, and plant secretions, but also steals seeds, attacks poultry chicks, disrupts bee hives, etc. Their habit of crawling over everything including refuse, sewage, sputum, carrion, etc. affords them the opportunity to transport the causative disease organisms for dysentery, etc.
Argentine ants invade buildings in large numbers when conditions outside are either too wet or too dry for them to live. Also, a decrease in their honeydew supply sends them indoors seeking sweets. They will readily trail along tree and shrub branches, as well as utility lines/wires to gain entrance
Pest Control of Argentine Ants
Location of the nest(s) and its treatment with a residual insecticide is ideal; try following ants back from the food source. Be sure to pull back the grass from around foundation walls and the edges of concrete sidewalks and driveways because these ants will trail below the grassline where they are not visible. Exterior baiting with liquid formulations is helpful, but should be used in combination with an outside perimeter treatment, which is essential and must be well maintained; nonrepellent pesticides work best. Be thorough and include treatment up under the siding-to-foundation wall junction if such is present. Seal all electrical and utility line entrances. Be sure to trim back all vegetation that is in contact with the structure.
Inside, be sure to check any potted plants present because these are a favorite nesting site. The light application (misting or spritzing) of a nonrepellent pesticide directly onto the foraging trails of ants is very helpful. This will usually give results is a few days at most. Be sure to cover any surfaces below the application site with plastic before application to avoid unwanted contamination.
What does an Argentine ant look like?
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Introduction to Pavement Ants
This ant gets its name from commonly locating its nest in or under cracks in pavement. Pavement ants were introduced from Europe by the early colonists. They are found in most of the eastern half of the United States and on the west coast in California and Washington.
Recognition of Pavement Ants
Workers monomorphic, about 1/16-1/8″ (2.5-3 mm) long; queens about 1/4″ (6 mm) long. Body light brown to black with paler legs and antennae. Head and thorax furrowed/grooved with parallel lines. Antenna 12-segmented, with 3-segmented club. Thorax with pair of small spines on upper back part, profile unevenly rounded. Pedicel 2-segmented. Stinger present.
Swarmers can be distinguished from other ant swarmers by the presence of fine furrows/grooves on their head and thorax, similar to those of the workers.
Similar Groups to Pavement Ants
(1) Harvester ants (Pogonomyrmex spp.) have underside of head with a brush of long bristles (coarse hairs/setae).
(2) Acrobat ants (Crematogaster spp.) with pedicel attached to upper surface of abdomen (gaster), gaster heart-shaped.
(3) Other small dark ants with only 1 node/segment in pedicel or if with 2 nodes, then thorax lacks spines on upper surface.
Biology of Pavement Ants
Very little work has been done on this ant. Colonies are moderately large to large, averaging 3-4,000 ants and several queens. Developmental time varies from 36 to 63 days. Winged reproductives appear outside primarily in June and July, but may emerge anytime inside including during the winter months. Workers have been shown to be an intermediate host of the poultry tapeworms Raillietina tetragona (Molin) and R. echinobothrida (Mednin).
Habits of Pavement Ants
Inside, pavement ants will occasionally nest in walls, in insulation, and under floors. The most likely place is in ground-level masonry walls of the foundation and especially near some heat source in the winter. They often follow pipes that come through slabs for access to upper floors of buildings. Swarmers typically emerge from expansion cracks/joints, from around floor registers, and from under baseboards. They will go up masonry walls and emerge into false ceilings and then come down into occupied areas below in commercial buildings.
Outside, these ants typically nest under stones, in cracks in pavement, and next to buildings. They enter buildings through cracks in the slab and walls, slab expansion joints, and the natural openings of buildings. When they excavate for a nest, they typically bring soil up to the surface and pile it up around the entry hole. Although not aggressive, workers can bite and sting.
These ants feed on almost anything including live and dead insects, honeydew (they will tend honeydew-producing insects, including subterranean species), seeds, plant sap, and household foods such as meats, nuts, cheese, honey, and bread, but show a preference for meats and grease. They forage in trails, and for distances of up to 30 feet (9m).
Control of Pavement Ants
Control is a 3-step process. First, location of the nest(s) is crucial and can often be accomplished by following the trail of foraging workers back from the food source. Treat the nest(s) directly with an appropriately labeled pesticide.
Second, a thorough perimeter treatment with a nonrepellent pesticide is highly effective in eliminating the ant problem; be sure to treat up under the bottom siding-to-foundation wall junction if present. In addition, all branches of trees and shrubs in contact with the building must be trimmed back. Be sure to check where electrical and water lines enter the building and caulk any gaps.
Third, lightly mist/spritz all foraging trails of ants with a nonrepellent pesticide. This step is very necessary for colonies located within the structure and it will speed up the control process for those coming in from the outside. This outside-inside combo treatment will usually give results is a few days at most. Be sure to cover any surfaces below the application site with plastic before application to avoid unwanted contamination.
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What do Pavement Ants look like?
Introduction to Fire Ants
These ants get their common name from their ability to inflict especially painful bites and stings. The two most important species are the southern fire ant (Solenopsis xyloni McCook) and the red imported fire ant (RIFA; Solenopsis invicta Buren). The southern fire ant is a native species and ranges from California to southern South Carolina to northern Florida. The red imported fire ant, introduced between 1933 and 1945, is from central Brazil and is now found in the southeastern United States, from Virginia south through Florida and westward through Texas, in southern New Mexico, southern California, and also in Puerto Rico. It is periodically found in other areas of the United States, usually associated with nursery stock. In 2006, the USDA reported that the RIFA exceeded $6 billion-a-year in damage and control costs.
Recognition of Fire Ants
Workers polymorphic, about 1/16-1/4″ (1.6-6 mm) long; queens average 1/4″ (6.6 mm, but up to 8 mm) long. Head and thorax yellowish red and abdomen black; reproductives darker with males black. Antenna 10-segmented, with 2-segmented club. Thorax lacks spines, profile unevenly rounded. Pedicel 2-segmented. Stinger extruded in most alcohol-collected specimens; readily inflict painful stings.
Characteristics of the mandible, clypeus (upper lip), and petiole (1st node of pedicel) will separate these 2 species. The mandible of S. xyloni has 3 distinct teeth on its inner/biting surface whereas, those of S. invicta have 4 teeth. The petiole of S. xyloni has a ventral tooth near the node’s attachment to the thorax whereas, S. invicta lacks such a tooth. In addition, the clypeus of S. invica has 3 small but distinct teeth or projections whereas, the clypeus of S xyloni has only 2 such teeth.
Similar Groups to Fire Ants
(1) Fire ant (Solenopsis geminata) with ridge on lower front margin of mesothorax having 1 or more teeth, 1st node in profile with rear margin almost straight.
(2) Little black ant (Monomorium minimum) with antenna 12-segmented, club 3- segmented.
(3) Acrobat (Crematogaster spp.), big-headed (Pheidole megacephala), harvester (Pogonomyrmex spp.), and pavement (Tetramorium caespitum) ants have spines on upper surface of thorax; in addition acrobat ants with heart-shaped abdomen and pedicel attached to upper surface of abdomen, big-headed ants with soldier with head very large and 3-segmented antennal club, harvester ants with underside of head with a brush of long bristles (coarse hairs/setae called psammophores), and pavement ants with head and thorax covered with distinct ridges.
(4) Other small dark ants have 1-segmented pedicel.
Biology of Fire Ants
For the red imported fire ant, single-queen (monogyne) mounds usually number 30-100/acre (0.4ha) with typically 80,000 but up to 250,000 individuals per colony. Multi-queened (polygyne) colonies may number 200-700/acre (0.4ha) but contain fewer individuals per colony, and there is less fighting between the colonies. Typical mounds are rounded, being up to 18″ (48 cm) high and 24+” (61+ cm) in diameter, each with several tunnels just under the soil surface extending out several feet. Single-queen colonies are territorial and reproduce by swarming whereas, multi-queened colonies are not territorial and reproduce by both swarming and budding. A queen in a large monogyne is capable of producing her own weight in eggs each day or about 1,500 or more; polygyne queens produce fewer eggs. Developmental time (egg to adult) for workers ranges from 22-38 days. After founding, a colony can mature (become capable of producing swarmers) in 1 or 2 years. Mature colonies can produce as many as 4,500 swarmers during a year, with 6-8 mating flights occurring between spring and fall. Mating flights usually begin about 10 am, 1-2 days following a rain if it is warm (about 75°F/24°C), sunny, and not very windy. Minor workers live 30-60 days, intermediates (medias) 60-90 days, and majors 90-180 days or longer. Queens live 2-6 years. Males die shortly after mating.
Typical mounds of the southern fire ant are flattened and irregular, covering 2-4 sq ft (0.17-0.37 sq m). Swarms occur from May through October in the afternoon to early evening of warm days. Developmental time can require as few as 44 days. Its biology has not been thoroughly studied.
Habits of Fire Ants
Fire ants are typically ground-nesting ants. However, the southern fire ant will sometimes nest in the wood or masonry of buildings, especially in areas near the soil or warmth such as fireplace hearths. When the southern fire ant nests outside near a house, it is usually in the vicinity of the kitchen. Outside nests are usually situated under stones or other covering objects, or in the soil at the base of a tree or shrub, or in clumps of grass.
The red imported fire ant typically nests outside. However, they will sometimes nest in areas of exposed soil within buildings such as bath traps. They also have the habit of building outside nests adjacent to foundation walls. They are commonly introduced into new areas via potted or balled shrubs and trees. When exposed to flooding, the displaced colony will form a ball and raft the flood waters until it encounters dry land. Such ants typically arrive hungry and with a defensive attitude (they inject higher doses of venom), probably because of their vulnerability due to a lack of protection normally afforded by their nest.
Attacks on non-responsive residents (usually the elderly or infants) of health-care or extended-care facilities typically occur in the morning, following a heavy rain and/or flooding. The displaced ants usually gain entrance into the structure through the HVAC system, such as wall A/C units. Typically, they enter seeking food. Several such incidents have resulted in the death of the person receiving multiple stings. In addition, about 1-2% of the United States population is thought to be at risk of anaphylactic shock when stung.
Fire ants are attracted to electrical junction boxes of traffic signals, air conditioners, etc. When they mass around the electrical contact points, they cause the equipment to malfunction. The attraction comes from one or more ants getting an electrical shock by completing the circuit. The shock stimulates the release of the defensive or under-attack pheromone, which attracts more ants, etc. They will also nest in gas and water meter boxes and then follow the pipes into the building.
Fire ants prefer food with a high protein content but will feed on almost anything, plant or animal. The southern fire ant has been known to remove insulation from phone and electrical wires, and to gnaw on clothing, especially if soiled. They usually feed on seeds, insects, young tree bark, honeydew and other sweets, preferring oily meats and nuts. Red imported fire ants are particularly destructive to vegetation. Workers forage in established trails.
Pest Control of Fire Ants
Fire ant control is difficult. Elimination from a single property is possible for up to a season, but scheduled inspections and retreatment will be required because of periodic reinvasion. There are presently about 5 control choices. It should be noted that when using baits, with one exception, they should be applied when the ground is dry and no rain is expected for 24 hours. Also, they should not be applied in the heat of the day when than ants are not actively foraging; late afternoon is usually best.
- Individual mound injection. This involves a thorough inspection to locate each mound and then treating each mound with a termite rodding tool hooked up to a termite or similar rig. It is a quick kill for the mounds treated, but the many small mounds will be missed. This means multiple treatments over the season.
- Broadcast application with the 2-step method. This consists of a broadcast application with slow-acting bait, and then waiting 5-10 days for it to be distributed within the colony. Then individual mounds are treated with a fast-acting liquid, dust, or granules (must be watered in) to kill most of the remaining ants. One or 2 applications are required each year.
- Broadcast treatments with several applications per year. These applications involve baits that contain both an IGR and faster-acting pesticide. The slower the action, the longer the period between applications.
- Broadcast application with the quickest kill. One of the newer baits on the market will give control in about 2-3 days. A second application may be required in 3-4 months. Best used when the ants must be eliminated in a hurry around sensitive accounts.
- Broadcast application with one treatment per year. One bait on the market usually requires only one application each year, but must be watered in to achieve control in 2-3 days. It can be applied just before or after a rain. This tends to cost more, but requires fewer applications.
What do Fire Ants look like?
Introduction to Crazy Ants
This ant’s name comes from the worker’s habit of running in an erratic, jerky manner when searching for food. The crazy ant is found throughout the United States, but is confined to the indoors in the northern states because it cannot survive the winter outdoors.
Recognition of Crazy Ants
Workers monomorphic, about 1/16-1/8″ (2.2-3.0 mm) long. Body dark brown to black with gray sheen/luster, slender. Antenna and legs very long in comparison to body size; antenna 12-segmented, without a club, and 1st antennal segment (scape) length about twice head length. Thorax lacks spines, profile unevenly rounded. Pedicel 1-segmented. Gaster with anal opening circular, surrounded by circlet of hairs. Stinger absent.
Similar Groups to Crazy Ants
(1) Paratrechina bourbonica (Forel) ants are more robust, with shorter legs, and antennal scape with many hairs readily apparent.
(2) Argentine (Linepithema humile) and odorous house (Tapinoma sessile) ants have anal opening slitlike, lacking circlet of hairs, and legs not exceptionally long in relation to body size; in addition, odorous house ants with pedicel/node nearly hidden by front edge of abdomen/gaster and emit a sweetish rotten coconut odor when crushed.
(3) Dark field ants (Formica spp.) have antennal scape (1st segment) less than 2 times head length.
(4) Other small dark ants have 2-segmented pedicel.
Biology of Crazy Ants
The colonies tend to be small, composed of up to 2,000 workers. Such a colony commonly contains 8 to 40 queens. Colonies are highly adaptable, nesting in both very dry and moist habitats. Crazy ants are known to completely abandon one nesting site and move to another. Huge colonies composed of tens of thousands of workers have been found in debris piles and mulch beds. Although swarms have been observed, apparently most new colonies are created by budding. Males are frequently observed at lights. No intensive studies on its biology have been done.
Habits of Crazy Ants
Inside, these ants usually nest underneath floors or carpeting, in potted plants, and in wall voids, especially near hot-water pipes and heaters. The workers visit food sources following trails, foraging up to 100 feet (30 m) or more. The preferred foods are insects and sweets, but they will feed on almost any household food.
Outside, the nests are shallow and usually located in soil under objects or next to foundations, or in such places as cavities in plants and trees, trash, refuse, mulch, and in potted plants. Here, they feed primarily on live and dead insects, seeds, fruits, and honeydew from aphids (plantlice), mealybugs, and scale insects that they tend. They most often enter homes in the fall or after a rain because both conditions reduce their supply of honeydew.
Control of Crazy Ants
Location of the nest(s) is crucial and can often be accomplished by following the trail of foraging workers back from the food source. The application of a perimeter treatment of a nonrepellent pesticide is effective. Be thorough and include treatment up under the siding-to-foundation wall junction if such is present. Seal all electrical and utility line entrances. Be sure to trim back all vegetation that is in contact with the structure. Additionally, on the inside, the light application (misting or spritzing) of a nonrepellent pesticide directly onto the foraging trails of ants is very helpful. This combination treatment will usually give results in a few days at most. Be sure to cover any surfaces below the application site with plastic before application to avoid unwanted contamination.
The use of boric acid dust in the voids of outside ground-floor walls and infested interior walls may be helpful in the long term.
What does a Crazy Ant look like?
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Introduction to American Cockroach
The American cockroach is also called a “waterbug”, the “Bombay canary”, and the “Palmettobug”. Despite its name, the American cockroach is not native to North America but was introduced via ships from African the early 1600s. It is world-wide in distribution.
Recognition of American Cockroach
Adults about 1 3/8-2 1/8″ (34-53 mm) long. Color reddish brown except for a submarginal pale brown to yellowish band around edge of pronotal shield. Last segment of cercus at least 2 times longer than wide. Both sexes fully winged with wings of male extending beyond tip of abdomen whereas, female’s do not; poor to moderately good fliers.
Nymphal early instars uniformly grayish brown dorsally, paler ventrally, shiny; cerci slender, distinctly tapered from base with length about 5 times width. Later instars reddish brown with lateral and posterior margins of thorax and lateral areas (sides) of abdominal segments somewhat darker; cerci slender, distinctly tapered with length about 5 times greatest width, widest segments 2.5 times as wide as long. Antennae uniformly brown.
Ootheca or egg capsule dark reddish to blackish brown; about 3/8″ (8 mm) long, with length about 1.5 times width; subdivisional furrows not extending to midwidth; weak terminal point; and usually with 8 eggs on each side.
Similar Groups to the American Cockroach
(Adults only).
(1) Brown cockroach (Periplaneta brunnea) with last segment of cercus short and triangular, length less than twice width.
(2) Australian cockroach (P. australasiae) has front wings with outside margin at base pale yellow.
(3) Smokybrown cockroach (P. fuliginosa) with pronotal shield uniformly dark.
(4) Other cockroaches are either much smaller or larger, lack characteristic pale markings, and/or are not associated with structures.
Biology of the American Cockroach
The female deposits her ootheca within a few hours or up to 4 days after it is formed. It is dropped or glued with a mouth secretion to a suitable surface, usually in a crack or crevice of high relative humidity near a food source. On the average, the female will produce about 9-10 (range 6-14; maximum 90) oothecae with each containing 14-16 eggs. Developmental time (egg to adult) is greatly influenced by temperature, varying from 168-786+ days but averaging about 600 days under ordinary room conditions. During this time, they molt 10-13 times. Adult females live about 440 days (range 102-588; maximum 913) at ordinary room conditions, but at 84°F/29°C, adult females live about 225 days (range 90-706) whereas, adult males live about 200 days (range 90-362).
Habits of the American Cockroach
Although American cockroaches are found in residences, they are much more common in larger commercial buildings such as restaurants, bakeries, grocery stores, food processing plants, hospitals, etc., where they usually infest food-storage and food-preparation areas, basements, and steam tunnels. During summer months, they can be found outdoors in yards and alleys. In the United States this is the most common species found in city sewer systems. More than 5,000 individuals have been found in a single sewer manhole.
They can enter structures by being brought in, coming up from the sewer system via drains, or occasional mass migration from other structures, dumps, etc., during warm weather. Although they feed on many kinds of food, they show a particular fondness for fermenting food.
Control of the American Cockroach
Follow standard control procedures but do not forget to check the drains. For sewers, power dusting with silica gel is particularly effective.
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What does the American Cockroach look like?
Introduction to the German Cockroach
The German cockroach is by far the most important and usually the most common of the cockroaches. In addition to being a nuisance, it has been implicated in outbreaks of illness, the transmission of a variety of pathogenic organisms including at least one parasitic protozoan, and allergic reactions in many people. This species has worldwide distribution.
Recognition of the German Cockroach
Adults about 1/2-5/8″ (13-16 mm) long. Color light brown to tan except for 2 dark, almost parallel longitudinal stripes/bars/streaks on pronotal shield. Female darker than male, her abdomen broader. Rarely glide or “fly”.
Nymphal instar 1 with 24 or 25 antennal segments, instars 1-2 with thorax dark brown to black but having pale lateral margins, meso- and metathorax pale/white centrally but with a continuous dark stripe near each margin; thorax and abdomen light brown ventrally. Later instars (3rd on) with 2 dark longitudinal stripes on pronotum continuous with dark abdomen, and abdominal segments usually with central areas pale but lightly pigmented on dorsum as are abdominal margins.
Ootheca or egg capsule yellowish brown but usually two-toned, paler end attached to female; about 1/4-3/8″ (6-9 mm) long and extending beyond wing tips, with length more than twice width; subdivisional furrows extending entire width; slightly bowed or arched; and with about 15-20 (range 9-25) eggs on each side.
Similar Groups to the German Cockroach
(Adults only).
(1) Asian cockroach (Blattella asahinai) with almost identical color pattern, attracted to lights, flies readily, breeds outdoors in leaf litter, presently known only from Florida, identification should be confirmed by an expert.
(2) Brownbanded cockroach (Supella longipalpa) and Pennsylvania wood cockroach (Parcoblatta pensylvanica) lack 2 dark longitudinal stripes on pronotal shield.
(3) Field cockroach (B. vaga) with a median dark line between eyes on front of head.
(4) Other cockroaches are either smaller or larger, lack characteristic pronotal stripes, and/or are not associated with structures.
Biology of the German Cockroach
The female carries her ootheca until it is within 1-2 days of hatching, and then deposits it in a sheltered area/site. On the average, the female will produce about 5 oothecae (range 4-8), averaging 30-40 eggs (range 18-50) each.
Developmental time (egg to adult) usually varies from 54-215 days, averaging about 103 days; under lab conditions of 80°F/27°C and 40% relative humidity, usually only 50-60 days are required. This means usually 3 to 4 generations per year, but up to 6. Adults live about 100-200 days (range 1-303). Established/mature German cockroach populations are typically composed of at least 75% nymphs.
Habits of the German Cockroach
German cockroaches are found throughout structures but show a preference for warm (70°F/21°C) and humid places. They are usually found in kitchens and secondarily in bathrooms, but infestations often occur in rooms where people eat and drink while watching television such as the den, bedroom, etc. Any crack or crevice located near a source of food and/or water is prime harborage, and they spend about 75% of their time in such harborages. First instar nymphs require a crack of about 1/32″ (1 mm) whereas, adults require a crack of about 3/16″ (5 mm) in width.
These cockroaches are most commonly introduced into buildings via paper products or paper packaging such as grocery bags, cardboard boxes, drink cartons, and via secondhand appliances such as refrigerators, televisions, VCR’s, microwaves, etc. They have been observed to migrate from building to building on warm evenings, but this rarely occurs. Although uncommon, they can survive outdoors during the warm months.
They feed on almost anything with nutritive value including all kinds of food, and such things as soap, glue, and toothpaste.
Activity periods vary with life stage, age, and physiological state. For instance, reproducing females are quite active whereas, gravid (with ootheca) females are relatively inactive starting about the 5th day after mating and go only to food and water when necessary. Males spend most of their time in harborage, even at night. All nymphs become immobile and stay in harborage during the last 3 days of each instar while they prepare to molt. Hence, about 1/3 of the time the cockroach nymphs will not be found or found exposed during an inspection.
Control of the German Cockroach
Follow the standard control procedures but more frequent service may be required because of their rapid reproductive rate. At least 95% of the population must be eliminated on the initial or clean-out service, or the typical maintenance program will usually fail. Baits are particularly effective, but correct placement along junctions and/or in cracks and crevices in or near harborages is essential. Incorporating IGRs (insect growth regulators) into the service helps with long-term control. Be sure to follow label directions.
What does the German Cockroach look like?
Introduction to Oriental Cockroach
Contrary to its common name, the oriental cockroach is thought to be of north African origin. It is also commonly called a “black beetle” or “waterbug” or “shad roach.” This species has worldwide distribution.
Recognition of Oriental Cockroach
Adult males about 1″ (25 mm) long whereas, females about 1 1/4″ (32 mm) long. Color usually shiny black but may vary to dark reddish brown. Male’s wings cover about 75% of abdomen, leaving 3 to 5 abdominal segments exposed. Female with much reduced wings which resemble nymphal wing pads but have veins. Adults do not fly.
Nymphal early instars shiny reddish brown, cerci rounded laterally and broadly tapering to tip, widest near center. Later instars dark reddish brown to black, cerci rounded laterally and broadly tapering to tip, widest near center with middle segments about 3 times as wide as long, and length about 3 times greatest width.
Ootheca or egg capsule reddish brown when deposited, then changing to black; about 3/8″ (8-10 mm) long, with length about 1.5 times width; subdivisional furrows extending from less than midwidth to beyond midwidth but are not entire; prominent terminal point; and usually with 8 eggs on each side.
Similar Groups to Oriental Cockroaches
(Adults only).
(1) Smokybrown cockroaches (Periplaneta fuliginosa) with wings extending to tip of abdomen.
(2) American cockroach (P. americana), Australian cockroach (P. australasiae), and brown cockroach (P. brunnea) with wings extending to tip of abdomen and with pale markings.
(3) Other cockroaches are either smaller or larger, have fully developed wings, are not uniformly black in color, and/or are not associated with structures.
Biology of Oriental Cockroach
The female usually deposits her ootheca within about 30 hours (range 12-120) after it is formed. It is either dropped or glued to something in a warm protected area near a food source. On the average, the female will produce about 8 (range 1-18) oothecae with each containing about 16 eggs.
Developmental time (egg to adult) is influenced by temperature, varying from 206-800 days but it takes about 575 (males) and 602 (females) days at ordinary room conditions. Adult females live 34-181 days whereas, males live 112-160 days.
Habits of Oriental Cockroach
In many areas, the oriental cockroach survives quite well outdoors and spends considerable time there. It is typically found under debris, stones, and leaf litter, but also in wall and porch voids. It has been observed to survive outdoors during 13 weeks of almost continuous freezing weather.
They usually enter buildings via door thresholds, under sliding glass doors, along utility pipes and air ducts, through unscreened ventilators, and from floor drains. Indoors, they are typically found in crawl spaces, cellars, basements, and on the first floor but at times on higher floors, especially around water pipes which they typically climb.
They feed on all kinds of food and decaying organic matter, but prefer to feed on starchy foods. They are much despised because of their strong “roachy” odor and because they feed on filth.
Control of Oriental Cockroach
Follow the standard control procedures but pay particular attention to damp crawl spaces, basements, and floor drains. Outside perimeter/barrier treatments are quite effective, especially when microencapsulated or wettable powder formulations are used.
What does an Oriental Cockroach look like?
Introduction to the Turkestan Cockroach
The common name probably comes from its having been collected in the Asian province of Turkestan. Its distribution is Egypt, Libya, Sudan, Saudi Arabia, Israel, Jordan, Iraq, Iran, Pakistan, India, the Soviet Central Asia, Kashmir, Afghanistan, and the United States. In the United States it is established in San Joaqnin, California (1978), El Paso, Texas (1979), and Maricopa and Pima, Arizona (1985). This species was introduced into California and Texas with the household goods of military personnel when they returned from the Middle East.
Recognition of the Turkestan Cockroach
Adult males about 1/2-7/8″ (14-23 mm) long whereas, females about 3/4-1″ (19-25 mm) long. Male with wings brownish yellow except basal outer edge pale/lighter and pronotum reddish brown with 2 wide lateral/side marginal transparent yellow bands; female body dark brown to black, short wings with basal outer edge pale, and pronotum with scattered paler areas. Legs have 1st and 2nd pair with femora bearing numerous, similarly-arranged stout spines on both ventral margins; 1st segment of hind leg tarsi as long as or slightly longer than segments 2-5 combined, and with pulvilli (ventral pads) of segments 2-3 small, much shorter than their respective segments. Male supraanal plate (terminal abdominal segment) with apex broadly notched (indented). Wings of male extend beyond abdomen, wings of female very short, present as small triangular pads separated by a distance less than a wing width.
Nymphal instars bicolored, with thorax light chocolate brown and abdomen very dark brown.
Ootheca or egg capsule dark brown; about 3/8-1/2″ (9-12 mm) long; keel with 14-22 denticles (teeth), shallow depressions between denticles; ootheca rounded on one end, truncate dorsally on other end with terminal point; subdivisional furrows extending to much less than midwidth; and usually with 9 eggs on each side.
Similar Groups to the Turkestan Cockroach
(Long-winged).
(1) Australian cockroach (Periplaneta australasiae) with front wings much darker (reddish brown), pronotum with pale yellow submarginal band extending across basal margin, and supraanal plate (terminal abdominal segment) with apex deeply notched.
(2) Surinam cockroach (Pycnoscelus surinamensis) with pronotum dark brown to blackish except for front and side margins usually yellow.
(3) American (Periplaneta americana) and brown (P. brunnea) cockroaches lack pale basal outer margin to front wings, pronotal markings somewhat indistinct, and supraanal plate with apex deeply notched.
(4) Other cockroaches either smaller or larger, with different coloration, and/or not associated with structures.
Similar Groups to the Turkestan Cockroach
(Short-winged).
(1) Female oriental cockroach (Blatta orientalis) with front wings separated by a distance greater than a wing width.
(2) Florida woods cockroach (Eurycotis floridana) longer, at least 1 1/8″ (30 mm) long, with front wings almost touching along midline, and hind leg 1st tarsal segment as long as or slightly longer than segments 2-5 combined.
(3) Harlequin cockroach (Neostylopyga rhombifolia) dark brown with a conspicuous pattern of yellowish areas, front wings separated by a space greater than a wing width.
(4) Other cockroaches either smaller or larger, with different coloration, and/or not associated with structures.
Biology of the Turkestan Cockroach
Apparently little is known about this species, but its biology is reported to be similar to that of the oriental cockroach.
At 86-95°F (30-35°C), nymphs develop in 118-137 days. Optimum embryonic development occurs at 86°F/30°C. Adults live for 30-300 days.
Habits of the Turkestan Cockroach
The Turkestan cockroach is a desert species which also inhabits semi-desert locations and sometimes lives under moist conditions. It is found both outdoors and inside structures. In California it inhabits warehouses and steam tunnels.
This species is common in sewer systems and is capable of carrying bacteria which cause dysentery.
Control of the Turkestan Cockroach
Follow standard control procedures but do not forget to check drains. For sewers, power dusting with silica gel is particularly effective.
Outside, practice good sanitation by the removal of debris and litter. A perimeter treatment using an appropriately labeled pesticide may be required. Baits should be an effective control method and should be tried first.
What does the Turkestan Cockroach look like?
Introduction to the Brownbanded Cockroach
Brownbanded cockroaches get their common name from the pale brown bands which run across the wings of the adult, but more appropriately, from the pale brown bands which run across the body of the nymph. This species is apparently of African origin and was presumably introduced from Cuba into Florida about 1903. It now occurs throughout the United States.
Recognition of the Brownbanded Cockroach
Adults about 1/2″ (male 13-14.5 mm; female 11-12 mm) long. Color light brown to brown with females much darker than males; head brown, pronotal shield with brown liberty-bell shaped pattern formed by translucent lateral margins or sides, and wings darker at base but paler towards their tips with exception of a pale band at their base and another about 1/3 from base. Female darker than male, her abdomen much broader and more rounded, and her wings do not completely cover the abdomen as they do in males. Males readily fly, but females cannot fly.
Nymphal instars 1-2 with thorax dark brown to black, but having pale lateral margins, mesothorax with white central area, metathorax pale/white its entire width or at least on its posterior half, abdomen with white central area; thorax and abdomen pale/white ventrally. Later instars (3rd on) with pronotum having a dark liberty-bell shaped pattern formed by pale/clear lateral margins, meso- and metathorax mostly white but white areas of mesothorax usually divided by dark posterior and sublateral margins; abdomen with 1st segment dark, next 4 segments dark laterally on dorsum.
Ootheca or egg capsule light brown; length about 1/4″ (5 mm) or less, with length less than twice width; subdivisional furrows extending entire width; bottom straight, top slightly bowed or arched; and with 8-10 subsegments but only 7-9 eggs on each side.
Similar Groups to the Brownbanded Cockroach
(Adults only).
(1) German cockroach (Blattella germanica), Asian cockroach (B. asahinai), and field cockroach (B. vaga) have 2 dark longitudinal stripes on pronotal shield.
(2) Pennsylvania wood cockroach (Parcoblatta pensylvanica) lacks dark liberty-bell shaped pattern on pronotal shield and cross bands on wings.
(3) Other cockroaches are either smaller or larger, lack characteristic pronotal and wing color patterns, and/or are not associated with structures.
Biology of the Brownbanded Cockroach
The female carries the ootheca for 24-36 hours and then attaches it, usually to the side or undersurface of shelves, furniture, etc. On the average, the female will produce about 14 egg capsules with each containing about 14-18 eggs (range 10-18), with an average hatch of 13-14 per egg capsule.
Developmental time (egg to adult) is greatly influenced by temperature, varying from 90-276 days but averaging about 161 days. Adults live about 206 days (range 131-315).
Habits of the Brownbanded Cockroach
Brownbanded cockroaches are found throughout structures but show a preference for warmer areas, over 80°F (27°C). Be sure to check ceilings, anything high on walls such as picture frames and wall molding, near appliance motors, and in light switches, closets, and furniture.
Control of the Brownbanded Cockroach
Follow standard control procedures but remember their preference for warm places.
What does the Brownbanded Cockroach look like?
Have a black widow problem?
Introduction to the Black Widow Spider
These spiders get their common name from the popular belief that the female eats the male after mating, a phenomenon which rarely happens in nature. The genus Latrodectus is worldwide in distribution, with 5 species occurring in the United States. Recognition of the genus is sufficient for PMP purposes.
Recognition of the Black Widow Spider
Adult female body length about 1/2″ (12-13 mm) including an almost spherical abdomen about 1/4-3/8″ (7.2-9.6 mm) in diameter, with overall length including legs of about 1 1/2-1 3/8″ (38-43 mm); males about half female size. Color typically black, abdomen on ventral or underneath side with 2 reddish triangular markings usually joined to form a reddish hourglass-shaped marking but sometimes separated (“split-hourglass”) or only a single mark; usually with red markings above spinnerets in eastern species. Females usually black (occasionally brownish black; red widow of Florida with cephalothorax and legs usually bright orange, sometimes yellow or brick red); males usually with color pattern on dorsal or upper surface, pattern variable but typically consists of a median row of red spots with white lines or bars radiating out to sides. With 8 simple eyes, 2 lateral pairs almost touching. Last tarsal segment of 4th pair of legs with row/comb of serrated bristles on venter; all tarsi with 3 claws each.
Young spiders primarily orange and white but acquire more and more black as they mature, with markings very similar to those of males. With 1 or 2 reddish markings on underneath side of abdomen.
Similar Groups to the Black Widow Spider
(1) All other spiders lack a hourglass-shaped or split-hourglass marking on underside of abdomen and/or comb of serrated bristles on last tarsal segment of 4th pair of legs and 8 eyes with 2 lateral pairs almost touching.
Representative Speicies of Black Widow Spiders
Identification to species is left to experts since several species are involved and species separation is based primarily on differences in the male genitalia. Although a very brief description based on female coloration is given below, it must be realized that color and markings are not always reliable characteristics for separation of these species and that males are usually colored and marked quite differently.
- Latrodectus bishopi Kaston, the red widow. Cephalothorax reddish, abdomen black with reddish to orangish spots outlined by white, red marks on venter, and legs reddish; occurs only in central and southern Florida.
- Latrodectus geometricus (Fabricius), the brown widow. Color brown or grayish-brown, abdomen with 3 white spots on top, with a median white band on rear, with 4 diagonal white bands on either side, and with a yellow to orange hourglass mark on underside, legs dark banded/ringed; occurs only along the Gulf Coast of Louisiana and Mississippi, in southern Georgia, in Florida from Jacksonville southward, and recently established in southern California from San Diego to Los Angles.
- Latrodectus hesperus Chamberlin and Ivie, the “western” widow. Color blackish, abdomen with ventral red hourglass mark complete, anterior triangular part longer and broader than posterior triangle, red spot above anal tubercle (just above spinnerets) usually absent; occurs in the western United States and western Canada.
- Latrodectus mactans (Fabricius), the southern black widow. Color blackish, abdomen with ventral red hourglass mark complete, posterior half more a rounded rectangle than a triangle, often with a red spot just above anal tubercle (just above spinnerets), and/or with row of red spots dorsally along midline; occurs primarily from Massachusetts to Florida and west to Texas, Oklahoma, and Kansas, but is most common in the southern states.
- Latrodectus variolus Walckenaer, the northern black widow. Color blackish, abdomen usually with separated red hourglass mark, having posterior mark triangular and anterior mark rounded, dorsally with row of red spots along midline and diagonal white bands laterally; occurs in the same area as the black widow but is also found in the northern states and in Canada and is more common in the northern states.
Biology of Black Widow Spider
Female black widow spiders deposit their eggs in silken egg sacs which are about 3/8-1/2″ (9.5-12 mm) in diameter, can be constructed in 1-3 hours, and are white but soon turn pale brown. Depending on the species, the maximum number of sacs per female ranges from 6 to 21 and the average number of eggs per sac is about 185-464 (maximum 917). The sac’s outer covering is tough and closely woven. The incubation period ranges from 8 to 30 days.
When newly hatched, the spiderlings undergo the first molt within the sac. They go through 4 to 9 instars in 54 to 107 days respectively, with each instar having different coloration and/or color pattern.
Most of the spiders overwinter as immature individuals, develop into adults in the spring, and die in late July, taking nearly a year to grow from egg to adult. The maximum number of days survived after maturity ranges from 822 to 952 for females and 127 to 196 for males, depending on the species.
These spiders spin an irregular web and hang from it in an inverted or upsidedown position. The web is used to ensnare prey. The female avoids light in sheltered places, and tends to work her web at night.
In terms of toxic bites, only the female is of concern. The male’s poison/venom sacs cease development and he does not attack prey upon maturity. Spiderlings are poisonous when ingested until they are 18 days old, and then lose their toxicity; adults have a different kind of venom.
The black widow’s venom is a neurotoxin. The female is normally shy and retiring, but aggressively attacks immediately after egg laying and when guarding her eggs. The black widow bite is not always felt, so the only reliable evidence of a bite is a slight local swelling with 2 tiny red spots where the fangs entered. However, pain is usually almost immediate and reaches its maximum in 1-3 hours, continues for 12-48 hours, and then gradually subsides. The major symptoms are increased body temperature and blood pressure, profuse sweating, and nausea. There is an antivenom available. Immediately call a physician or go to an emergency room if bitten and take the spider along for identification purposes. If treated, bites are rarely fatal except occasionally in small children.
Habits of Black Widow Spider
Initially, the second instar spiderlings remain near the sac but within a few days they climb to a high point within suitable air currents, spin silk threads and float out on the breeze like kites. This “ballooning” provides for general dispersal of the species.
Outside, black widows commonly live in protected places among and under stones and pieces of wood, in firewood piles, under decks, in hollow stumps and trees, in rodent burrows, and less often in low tree branches or shrubbery. Favorite places are dry man-made structures including barns, outhouses, henhouses, sheds, meter boxes, brick veneer, barrels, and woodpiles.
Indoors, they are typically found in seldom-used parts of garages and basements and in crawl spaces, preferring the more cluttered areas because they provide more harborage for their prey which consists primarily of insects. Their webs are usually about 1 foot (30 cm) in diameter.
Control of Black Widow Spider
Follow the standard control procedures for spiders.
Have a black widow problem?
What does a Black Widow Spider look like?
Have a brown recluse problem?
Introduction to Brown Recluse Spider
The brown recluse or fiddleback/violin spider gets its common names from its coloration and reclusive habits, or the dark violin/fiddle-shaped marking on the top of the cephalothorax. Members of the genus Loxosceles occur in southern Europe, temperate Africa, and in North, Central, and South America. In the United States, brown recluse spiders occur throughout the south central Midwest from Ohio to Nebraska and southward through Texas to Georgia; specifically starting with central and southern Indiana southward through central and western Kentucky and Tennessee, northern Georgia, and all but extreme southeastern Alabama, then westward to northeastern and central Texas, and northward into central and eastern Oklahoma and Kansas, southeastern Nebraska, then eastward through southern Iowa, central and southern Illinois and back into central and southern Indiana; areas just outside of these locations may also have a few brown recluse spiders. Of the 11 species recognized, the 6 listed under representative species below are of public health importance. Recognition of the brown recluse species group is sufficient for PMP purposes.
Recognition of Brown Recluse Spider
Adults usually about 1/4-1/2″ (6-11 mm) in body length (L. laeta about 1/2″/13 mm in body length). Color tan to dark brown, usually with a darker fiddle-shaped marking on dorsum or top of cephalothorax whose neck points towards abdomen. Always with 6 eyes arranged in 3 groups of 2 each (diads) in a semicircle.
Immatures very similar to adults except for being smaller and slightly paler.
Similar Groups to Brown Recluse Spider
(1) Spitting spiders (Scytodes spp.) have 6 eyes arranged in 3 groups of 2 each, but also have many black spots or lines on their bodies.
(2) All other spiders lack 6 eyes arranged in 3 groups of 2 each and a darker fiddle-shaped marking on the top of cephalothorax.
Representative Species to Brown Recluse Spider
Because several species are involved and species separation is primarily by differences in male genitalia, species identification should be left to experts. Those of public health importance are:
- Loxosceles arizonica Gertsch & Mulaik which occurs in Arizona.
- Loxosceles deserta (Gertsch) which occurs in the southwestern United States.
- Loxosceles devia Gertsch and Mulaik which occurs in southern Texas.
- Loxosceles laeta (Nicolet) which has been found in Massachusetts and occurs in southern California.
- Loxosceles reclusa Gertsch and Mulaik, the brown recluse, which occurs in the south central Midwest (Nebraska to Ohio) southward through Texas to Georgia in the United States.
- Loxosceles rufescens (Dufour) which occurs sporadically throughout the United States as rare, spot infestations.
Biology of Brown Recluse Spider
This discussion is based on L. reclusa. The female deposits 40-50 eggs in a silken egg sac which is off-white, with the outer covering loosely woven. The sac has been described as either flat beneath and convex above (5/8″/17 mm in diameter and 1/8″/3.7 mm high) or as round (1/4″/6 mm in diameter). From 1 to 5 sacs are produced, each containing 31-300 eggs. The eggs hatch in 25-39 days and the spiderlings undergo at least 1 molt within the sac before emerging. The spiderlings typically go through 8 instars, and the development period (egg to adult) averages 336 days (range 266-444). Indoors, males live an average of 543 days, and females live 628 days, but 4-5 years is not uncommon.
The female spins an irregular web in undisturbed areas. The web is not used to ensnare prey, but mostly as a retreat for the spider.
Both male and female brown recluse spiders can inject venom, and must be considered dangerous to humans. Injection of their venom may produce necrosis or dead tissue, resulting in an ulcerating type of sore. The bite is usually not felt, but it may produce an immediate stinging sensation followed by intense pain or this reaction may be delayed for 6-8 hours. A small blister usually appears and the surrounding bite area becomes swollen. Symptoms include restlessness, fever, and difficulty in sleeping. The killed tissue gradually sloughs away during the next 10-14 days, leaving an open ulcer and possibly exposing the underlying muscles and/or bone. Healing is very slow and usually takes several weeks, resulting in dense scar tissue. In severe cases, plastic surgery may be required. An antivenom has been developed but it is NOT clinically available. Call a physician or go to an emergency room immediately if bitten, and take the spider along for identification purposes. It should be noted that not all brown recluse bites result in ulcer formation and that bites of other arthropods may cause similar reactions in people.
Habits of Brown Recluse Spider
Outside, brown recluse spiders are typically found around rocks, piles of inner tubes, utility boxes, woodpiles, under bark, etc. These spiders have been found in such places as outside rodent bait stations and infesting cedar shake roofs.
Inside the home, they can be found in almost any undisturbed area to which they can gain access. They are most commonly found in boxes, among papers, and in seldom-used clothing and shoes, although they can be found in corners, underneath tables and chairs, or in crevices such as those found along baseboards, doors, and window moldings. Hence, storage areas such as closets, bedrooms, attics, crawl spaces, and basements are the areas of greatest occurrence. They typically run for cover when disturbed. Bites have been reported to occur when putting on seldom-used clothing or shoes, when cleaning out storage areas, or by rolling on the spider while in bed.
In commercial buildings, the usual places to find brown recluse spiders include heat tunnels, boiler rooms, attics, basements, storerooms, and garages.
In the Midwest, in heavily infested homes, people are rarely if ever bitten. For example, in one house is Lenexa, KS, over 2,050 brown recluse spiders were found in 6 months, yet nobody in the family of 4 (2 adults, 2 teenagers) that lived in the house had been bitten in over 4 years of living there; in St. Louis, MO, a house had 45 brown recluse spiders and the family (2 adults, 2 small children) had lived there 2 years with no bites; and in Tulsa, OK, the house had 30 brown recluse spiders and the family (1 adult, 3 teenagers) had lived there 4 years with no bites.
With respect to food, brown recluse spiders prefer live small prey. If their prey is large, they prefer it to be dead, presumably to avoid damage to themselves. Their prey are primarily insects.
Control of Brown Recluse Spider
Follow the standard procedures for spiders, but check any cedar shake shingles present. Vacuuming up dead insects is advisible. The generous use of glue boards placed in areas where spiders have been seen or along walls can help locate and remove these spiders. Effective pesticide control usually involves its direct application to the spider. Control of severe infestations may require several months.
Clothes and shoes should not be left on the floor, or they must be shaken out before wearing. Especially if stored in the basement, garage, or other dark area, store seldom-used items such as boots, baseball mitts, skates, gardening clothes, and gloves in tightly sealed plastic bags or boxes.
Have a brown recluse problem?
What does a Brown Recluse Spider look like?
Introduction to Daddylongleg Celler Spiders
The common name cellar comes from these spiders being frequently found in dark and damp places such as cellars, basements, and crawl spaces, and that of daddylonglegs from their very long, thin legs which give them an appearance somewhat similar to harvestmen/daddylonglegs (order Opiliones, family Phalangiidae; see similar groups below). Cellar spiders are nuisance pests, probably more because of their webs than the spider itself. About 20 species are found in the United States and Canada.
Recognition of Daddylongleg Celler Spiders
Adult body length ranges from about 1/16-5/16″ (2-8 mm); cephalothorax and abdomen connected by tiny waist (pedicel) but appearing as small body with very long, thin legs. Color usually pale yellowish to light brown or gray. Usually with 8 eyes, some species with 6, usually with 2 widely spaced groups of 3 closely-spaced eyes each and 2 eyes in between. Chelicerae (fangs) fused at base, cheliceral claw short and opposed (closes to/opposite) by a short toothlike projection of basal segment. Abdomen either globose or elongate. Tarsi with 3 claws each.
Similar Groups to Daddylongleg Celler Spiders
(1) Harvestmen/Daddylonglegs (order Opiliones, family Phalangiidae) with cephalothorax and abdomen broadly connected giving appearance of singular oval body, 1 pair ocelli, and tarsi with 1 claw each.
Representative Species to Daddylongleg Celler Spiders
- Long-bodied cellar spider, Pholcus phalangioides (Fuesslin). Adult female body length about 1/4-5/16″ (7-8 mm) with front legs about 1 3/4-1 15/16″ (45-50 mm) long, male body length about 1/4″ (6 mm); with 8 eyes in 2 lateral groups of 3 each and 2 smaller eyes in between; abdomen elongate, cylindrical, about 3 times longer than wide; found worldwide.
- Short-bodied cellar spider, Spermophora meridionalis Hentz. Adult female body length about 1/16″ (2 mm) with front legs about 5/16″ (8.5 mm) long, male body length about 1/16″ (1.6 mm) with front legs about 3/8″ (9.5 mm) long; cephalothorax pale yellow with 2 light gray spots, abdomen pale yellow; with 6 eyes in 2 lateral groups of 3 each; abdomen globose; found in eastern United States.
Biology of Daddylongleg Celler Spiders
The long-bodied female cellar spider may produce up to 3 egg sacs containing 13-60 eggs each. The sacs are very thin such that the cluster of eggs shows through, giving the appearance of an unripened blackberry. The female typically carries the egg sac between her chelicerae (jaws) until they hatch. The emerging spiderlings often cling to their mother for a short time. There are 5 molts before maturity is reached, and this usually requires about 1 year. Adults typically live about 2 years.
The short-bodied female cellar spider produces a similar egg sac containing 10-27 eggs each, and also carries it in her chelicerae.
Habits of Daddylongleg Celler Spiders
Cellar spiders construct loose, irregular webs in corners. They hang upside down on the underside of the web. The webs are not cleaned but instead new web is continually added. This habit can result in extensive webbing in a relatively short time.
Webs are commonly found in dark and damp places such as cellars, basements, and crawl spaces. They can also be found in the corners of garages, sheds, barns, and warehouses, on eaves, windows, and ceilings, and in closets, sink cabinets, and bathtraps. In commercial buildings and warehouses, these spiders tend to be in corners near doors which are left open. Open doors allow many flying insects to enter which means more food.
Cellar spiders seem to fare better in areas with higher relative humidity (RH). The higher RH may be due to older construction, improperly vented crawl spaces, excessive ground moisture, improperly sealed basement walls, leaking/sweating plumbing pipes, leaky flashing, roof problems, etc. This increased RH attracts and helps support insect prey.
When disturbed on its web, the long-legged cellar spider has the habit of rapidly shaking its body in a rotary movement. This causes the web to vibrate enough to blur both spider and web, making the spider seem to disappear. If the disturbance is caused by insect prey, this vibration helps to further entangle the prey. If disturbed too much, the spider will retreat to a corner or drop from the web to escape.
Control of Daddylongleg Celler Spiders
Follow the standard control procedures for spiders outlined in the introductory section. Lowering the RH can be helpful in discouraging these spiders and their insect prey.
What do Daddylongleg Celler Spiders look like?
Introduction to the House/American or Common House/Domestic Spider
The common names reflect the fact that this is usually the spider most often encountered indoors. It is a nuisance pest, probably more because of its webs than the spider itself. This spider is found worldwide and is common throughout the United States and Canada.
Recognition of the House/American or Common House/Domestic Spider
Adult female body length about 3/16-5/16″ (5-8 mm) including an almost spherical abdomen, male body length about 1/8-3/16″ (3.8-4.7 mm) including an elongated abdomen. Color highly variable with carapace (cephalothorax dorsum) yellowish brown; abdomen dirty white with a few dark spots (sometimes with a black triangular spot in center of dorsum) to almost black, with several dark stripes meeting at angle medially (=chevrons/“army sergeant stripes”) above tip of abdomen; legs orange in male but yellow in female, with dusky ring at end of each segment (=banded). With 8 eyes, 2 lateral pairs almost touching. Last tarsal segment of 4th pair of legs with row/comb of serrated bristles on venter; all tarsi with 3 claws each.
Similar Groups to the House/American or Common House/Domestic Spider
(1) Other Achaearanea spp. lack chevrons on abdomen.
(2) Tidarren sisyphiodes with a distinctive white stripe on posterior of abdomen.
(3) Other spiders lack comb of serrated bristles on last tarsal segment of 4th pair of legs and 8 eyes with 2 lateral pairs almost touching.
Biology of the House/American or Common House/Domestic Spider
Female house spiders lay about 250 eggs (range 132-442) in a silken sac which is brownish, oval to flask-shaped, about 1/4-3/8″ (6-9 mm) in diameter, and with a tough, papery cover. There may be more than one sac in the web at a time; a female may produce up to 17 sacs, containing over 3,760 eggs, in her lifetime. The sacs are usually located in the center of the web but may be moved to warmer or cooler sites as required. The eggs hatch in about 7-10 days but the 1st instar spiderlings remain in the sac until they molt once. The 2nd instar spiderlings then emerge and balloon. Females molt 7 times and males 6 or 7 times to reach maturity. Adults may live for a year or more.
Habits of the House/American or Common House/Domestic Spider
The house spider randomly selects its web sites and creates a tangled web. If a web does not yield prey (food) it is abandoned, another site is selected, and a new web built. Eventually, successful webs are constructed where air currents bring in prey. Survival is low in modern homes with low humidity and few insects, higher in garages, sheds, barns, warehouses, etc. because of more prey and generally higher humidity, and highest outdoors in protected places.
Inside structures, house spiders are most likely to be found in upper corners, under furniture, in closets, angles of window frames, basements, garages, and crawl spaces. In warehouses, they are common in corners near doors that stay open. Outside, they are often around windows and under eaves especially near light sources which attract prey.
Because of their web site selection by trial and error, many webs may be constructed in several days. Dust collecting on these webs accentuates their presence. This situation is unacceptable in most households, offices, food processing plants, etc.
Control of the House/American or Common House/Domestic Spider
Follow the standard control procedures for spiders as outlined in the introductory section.
Use a vacuum to remove adults, egg sacs, and webs. If a broom is used, adults usually escape unless they are first individually treated with a nonresidual contact pesticide; this can leave marks or dirt/dust on wall and ceiling surfaces.
What does the House/American or Common House/Domestic Spider look like?
Introduction to the Hobo Spider
The common name comes from this spider’s method of very rapidly expanding its distribution by hitching rides with humans along major highways in the Pacific Northwest; it was formerly known as the aggressive house spider. Their webs are a nuisance. The allegation that their bite may cause a slow-healing lesion and is therefore of medical importance has yet to be proven. This species was introduced from Europe and first found in the Puget Sound ports in the 1930’s. It is currently common in the north- western United States (Idaho, western half of Montana, Oregon, east of the Great Salt Lake in northern Utah, Washington, western Wyoming, and in Colorado) and in southern British Columbia. The hobo spider appears to be rapidly expanding its range, displacing many native spiders as it spreads.
Recognition of the Hobo Spider
Adult female body length about 7/16-9/16″ (11-14 mm) including oblong abdomen, male body length about 5/16-7/16″ (7-11 mm); total size including legs about 1-1 3/4″ (40-50 mm) in diameter. Color variable with carapace (cephalothorax dorsum) light to medium brown, with dark stripe to either side of lighter midline stripe, dark stripe with lateral extensions in posterior half; abdomen with interrupted light midline stripe with about 5 light colored triangular shaped loops on each side bordered by a dark background but usually 1st 1 or 2 and last 2 or 3 loops incomplete, last 2 or 3 loops chevron-shaped (stripes meeting at angle medially; “army sergeant stripes”) with enlarged ends, white on darker dorsal coloration gradually changes to dark blotches on a lighter background on sides and venter; sternum (venter central area between coxae) with light midline stripe and usually solid dark lateral stripe on each side; legs solid light brown, no bands. With 8 eyes in 2 transverse lines/rows, front row slightly curved forward and rear row almost straight. Cephalothorax, abdomen, and legs with plumose (featherlike) hairs/setae (only visible under 30x or higher magnification). Abdomen with longer posterior spinnerets extending beyond abdomen, visible from above. Tarsi with 3 claws each.
Because color is so variable, examination of adult genitalia is best for positive identification. Male with inner surface of palp (side view; best to remove left palp) at tip of tibia (segment just before swollen apical segment) with a retrolateral tibial apophysis (RTA), a large structure composed of a single projection whose top is rather flat or squared off. Female with epigynum (opening to reproductive organs, located on underside of abdomen) with hardened cavity (atrium) in middle surrounded by 3 thickened raised ridges, 2 slanted white side ridges and 1 ridge below.
Similar Groups to the Hobo Spider
(1) Domestic (Tegenaria domestica (Clerck)) and giant (Tegenaria duel- lica [formerly T. gigantea]) house spiders with posterior line of 4 eyes curved rearward and sternum with lateral dark stripes containing 3 pairs of light circular marks each; in addition T. domestica has banded/ringed/annulated legs and T. duellica male palp RTA with 2 projections (1 on each end of a saddle) and female epigynum with no cavity/atrium (only a shiny flat surface) and with large spurs or projections near bottom that point toward each other.
(2) Grass spiders (Agelenopsis spp.; Agelenidae) with carapace (cephalothorax dorsum) yellowish to dark brown with 2 dark longitudinal stripes, abdomen yellowish gray to dark brown and patterned, and legs banded/ringed/annulated.
Biology of the Hobo Spider
Hobo spiders have a 2-year life cycle. Mating occurs in the autumn. In mid-September to October, the female spins a hemispherical silken egg sac into which she deposits her eggs. In the spring, spiderlings molt once within the sac before emerging as 2nd instars in early June. They molt a second time about one week after emergence and continue molting monthly for about 12-15 molts. They spend the second winter as immatures. Males mature the second summer from June through September, and females mature from late June to September. Mating occurs, and most males die before October. Females lay eggs in sacs until cold prohibits activity and usually die from late autumn to early spring. However, some females may live 3 or more years.
Only a few dozen bites, almost all are circumstantial, are attributed to this spider for several reasons. Rarely is the culprit caught in the act, captured, and/or properly identified. It is common for people to use home remedies and never see a physician unless severe conditions develop. Many physicians in the northwestern United States and adjacent Canada continue to attribute necrotic lesions to the brown recluse spider, which does not occur in this area, while others now attribute the cause to the hobo spider, which does occur in this area.
The hobo spider has been blamed for necrotic wounds since the late 1980s. However, recent research is investigating if its venom is active toxicologically. In its native Europe, the hobo spider is not considered to be medically important. Since no significant difference has been found in the venom in populations from the North America and Europe, the serious question arises if in fact hobo spiders have been wrongly accused of routinely/ typically causing dermonecrotic lesions. The following two paragraphs summarize what is presently in most of the literature, but because all the symptoms have been based on circumstantial evidence, none of the following may be valid.
The bite of these spiders typically produces a necrotic lesion similar to that caused by brown recluse spiders, Loxosceles spp. The initial bite produces a very slight prickling sensation. Within 3 minutes or less, a small, insensitive, hard area appears which is surrounded by an expanding reddened area of 2-6″ (51-153 mm) in diameter. Within 15-35 minutes the area blisters. About 24 hours later the blister usually breaks, and the wound oozes serum. The cratered ulcer crusts over to form a scab. Tissues beneath the scab may die and slough away; severe bites may require surgery to close. The fully developed lesion may be up to 1/2-1″ (12-25+ mm) or more in diameter. It may take several months to heal and often leaves a permanent scar.
Systemic illness occasionally occurs. The most common symptom is a severe headache, sometimes within 30 minutes but usually within 10 hours, which does not respond to aspirin and may last for 2-7 days. The headache may be accompanied by nausea, weakness, joint pain, fatigue, and vision impairment, symptoms commonly associated with migraine headaches. A low blood platelet count (<150,000) may occur at about 36 hours, which recovers in about 7-10 days. Antibiotics do nothing to alleviate the effects of the venom, although they are often prescribed. At least a couple of deaths may have resulted from hobo spider bites, but this has not been proven with solid evidence.
Habits of the Hobo Spider
Hobo spiders may be found in almost any habitat containing holes, cracks, or crevices which can support tunnel formation. Since they are poor climbers, they are rarely found above ground level. They frequent dark, moist areas, and are most often found in basements, window wells, and crawl spaces. Common web sites include rock retaining walls, soil and concrete cracks, the junction of foundations and tall grass, firewood and lumber piles, landscape timbers, stones and rocks partially raised above the ground, etc.
These spiders build funnel webs opening at both ends with one end expanding outward into a broad, slightly curved sheet. Vibrations from struggling prey (usually insects) ensnared on this sheet alert the spider which runs out of the funnel, bites the prey, and quickly carries it into the funnel. An escape tunnel is commonly built in the back of the web which leads to a deep crack or other protected area.
From late June to October (peak activity in August-September), males extensively wander about seeking a female mate; females are found most of year with peak activity in Spetember in coastal states and from August to October in other areas. It is not uncommon for several roving males to enter the ground level of a structure each day. Because they are poor climbers, they tend to be found mostly on the ground floor and in basements. It should be noted that males have been said to be more toxic than females, but until proof of their necrosis-inducing ability is established, this is still in question. Males are also responsible for more bites because this late-summer to early-autumn wandering habit brings them into contact with humans.
Immatures wander about in the spring in search of a web site. This wandering tends to bring them into contact with humans. They can be seen moving on floors or get trapped in various objects such as buckets, sinks, bathtubs, open jars, and children’s toys. Immatures can be found year-round in basements and garages behind stored items, behind furniture, under raised baseboard heaters, in closets, etc.
It should be noted that in human populaton centers where both species occur, the giant house spider, T. duellica, is typically more common that is the hobo spider, T. agrestis. In this situation, only in Portland, OR, has the hobo spider been found to be more abundant.
Control of the Hobo Spider
Follow the standard control procedures for spiders outlined in the introductory section. Outside, pay particular attention to tall or matted grass near the foundation. This should be removed and replaced with a gravel edging several inches wide around the foundation.
What does a Hobo Spider look like?
Introduction to Jumping Spiders
The common name comes from their jumping ability and habit which they use to capture prey. They are an occasional nuisance pest indoors, and some black colored species may cause concern when people mistaken them for black widow spiders, Latrodectus spp. About 300 species are found in the United States and Canada.
Recognition of Jumping Spiders
Adult body length about 1/8-3/4″ (4-18 mm); robust, compact with relatively short legs. With 8 eyes in 3 rows, front row of 4 eyes with middle pair very large, 3rd row of 2 moderately large eyes at about midlength of cephalothorax, and middle row of 2 small eyes about midway between 1st and 3rd rows. Color usually black, sometimes brown, tan, or gray, and usually with pale markings of white, gray, yellow, red, blue and/or green; typically densely covered with hairs or scales, these often brightly colored or iridescent. Front legs usually thicker and somewhat longer than other legs; tarsi with 2 serrate (toothed) claws each. No snare webs, quick to jump, with jumping power generally supplied by the 4th pair of legs.
Note that there are several genera with species which mimic ants, having cephalothorax slightly pinched in at middle to resemble head and thorax and front legs held up and bent like elbowed antennae; these species do not jump.
Similar Groups to Jumping Spiders
(1) Crab (Thomisidae) and giant crab (Sparassidae) spiders have body usually flattened with legs positioned/held at right angle to sides giving a crablike appearance and many species with horns or ornaments on cephalothorax and/or abdomen.
Representative Species of Jumping Spiders
- Phidippus audax (Hentz). Adult female body length about 5/16-5/8″ (8-15 mm), male about 1/4-1/2″ (6-13 mm); color blackish with basal white band and paired white (sometimes yellow or orange) spots on abdomen, largest spot (=fused 2nd pair) triangular, in center, and pointing towards front, sometimes cephalothorax with white lateral bands extending back from rear eyes and abdomen with lateral white bands and tan pattern; male (with swollen terminal segments of palps) with large blunt cusp/knob on front of each chelicera near fang; found throughout the United States and southern Canada.
- Zebra spider, Salticus scenicus (Clerck). Adult female body length about 3/16-1/4″ (4.3-6.4 mm), male 1/8-1/4″ (4-5.5 mm); color gray (often with brown to reddish scales intermixed) with white markings on cephalothoracic front (with iridescent scales), behind rear pair of eyes, and laterally, and on abdomen as basal band, middle band interrupted at midline, and rear band usually interrupted at midline, legs white or brown with gray rings; male with chelicerae elongate, extending almost horizontally forward, and fangs long and sinuate; found throughout northern United States and southern Canada.
Biology of Jumping Spiders
Jumping spiders do not construct snare webs but do build web retreats which are loosely woven, saclike, composed of several envelopes, and usually have 2 openings. These retreats are used for molting, hibernation, night-time seclusion, and egg laying; often a different retreat is built for each function/activity. The egg sacs are typically lens-shaped and suspended like a hammock from the retreat’s walls. There is usually only 1 egg sac, but occasionally there may be several present at one time.
In the New England states, Phidippus audax females lay their eggs in June and July. The egg sac is about 3/8″ (9 mm) in diameter and about 1/8″ (3.5 mm) thick. Each egg sac contains 67-166 orange eggs. The older spiderlings overwinter in the retreat and become adults in late April to early May. Adults are present through August.
In the New England states, the zebra spiders mate in May and eggs are laid in June and July. Each egg sac contains 15-25 white eggs. Presumably, the older spiderlings over- winter in the retreat and become adults in spring. Adult males are found April to July and females from mid-May to late October.
Habits of Jumping Spiders
Unlike most spiders, jumping spiders are active during the daytime and seem to like sunshine. They are hunters and have the keenest vision of all spiders, being able to detect and react to movement up to 18″ (45 cm) distant; however, their night vision is very poor. They can rapidly move both sideways and backward for short distances.
They are excellent jumpers. They either jump on passing prey, or once they locate prey, it is stalked and then pounced upon. When hunting they may jump 1″ or more (25+ mm) but when threatened, they may jump 20 times their body length. They employ silk as a dragline when they jump; the dragline is anchored before they jump and acts as a safety line.
Retreats may be built under furniture, in drapery folds, between books on bookshelves, in cracks such as found in wood floors, around door and window molding, etc. Outside, they can frequently be found under loose bark, between leaves, etc.
Indoors, they will usually be found hunting around windows and doors because more insects are attracted to these areas. Also, their vision is best in sunlit areas.
Outdoors, jumping spiders are commonly seen running over tree bark, under stones and boards, on bushes, fences, decks, and the outside of buildings, etc. They like sunny areas.
Pest Control of Jumping Spiders
Follow the standard control procedures for spiders outlined in the introductory section except pesticide application is rarely warranted. Exclusion and the removal of outdoor harborages is key. Indoors, removal with a vacuum is best followed by disposal of the vacuum bag outside.
What do Jumping Spiders look like?
Introduction to Wolf Spiders
The common name reflects that these are hunting spiders and will chase their prey; the family name and typical genus Lycosa are from the Greek word for wolf. These spiders are often big and hairy which alarms some people, but they are primarily nuisance pests. Over 100 species occur in the United States and Canada. This section will be restricted to members of the genus Hogna (over 30 spp.) that contains the large and hairy species of wolf spiders.
Recognition of Wolf Spiders
Adult female body length 3/8-1 3/8″ (9-35 mm), male body length 1/4-3/4″ (6-20 mm); cephalothorax and abdomen very hairy. Color usually dark brown, often with paler stripes or markings, or sometimes yellow with dark stripes or markings. With 8 dark eyes, front row of 4 small, evenly spaced, eyes slightly curved towards rear medially, posterior row strongly curved forward medially forming 2 rows, center/front 2 eyes very large and lateral/posterior 2 eyes of intermediate size; appear as 3 rows of 4, 2 and 2. Cephalothorax (in lateral view) with front eye area raised above posterior half. Chelicerae moderately long, strong, with 3 teeth on fang furrow retromargin (side opposing fang). Labium longer than wide. Abdomen with posterior spinnerets at most only slightly longer than anterior ones. Legs long and spiny, tibiae of 1st and 2nd pair of legs with last pair of ventral spines apical, tibia of 4th pair of legs with 3 spines of about equal thickness/stoutness across dorsum, and metatarsus (1st tarsal segment/6th segment from body) of 4th leg less or not longer than its tibia and patella (segment between femur and tibia) combined. Tarsi with 3 claws each, center claw very small.
Similar Groups to Wolf Spiders
(1) Other genera of wolf spiders (Lycosidae) without the above combination of characters, and usually smaller.
(2) Nursery web and fishing spiders (Pisauridae) with 8 eyes about equal in size, front row of 4 slightly curved downward/forward, and female carries egg sac in her chelicerae (jaws).
(3) Lynx spiders (Oxyopidae) with 6 large eyes forming a hexagon and 2 smaller eyes below, and abdomen pointed.
(4) Ground spiders (Gnaphosidae) with posterior row of 4 small eyes almost straight, front spinnerets cylindrical and separated, and abdomen long and somewhat flattened.
(5) Funnel-web weavers (Agelenidae) with 8 eyes, front row consisting of 2 widely spaced (same spacing as rear 2 eyes) eyes, each with 2 stacked almost touching eyes to outside, posterior (rear most) spinnerets longer than other spinnerets.
Representative Species of Wolf Spiders
- Hogna aspersa (Hentz). Adult female body length 3/4-1″ (18-25 mm), male 5/8-3/4″ (16-18 mm); color brown, carapace (cephalothorax dorsum) dark brown with gray hairs (somewhat lighter in males to yellowish brown) and without distinct markings except for a distinct narrow line of yellow hairs in eye region, abdomen brown with slightly darker median longitudinal stripe, venter black but spotted, and legs annulate/ringed; usually builds a burrow in ground; found in New England and adjacent Canada south to Florida and west to Nebraska.
- Hogna carolinensis (Walckenaer). Adult female body length 7/8-1 3/8″ (22-35 mm) with leg span of about 3″ (75 mm), male body length 3/4″ (18-20 mm); color brown, carapace (cephalothorax dorsum) dark brown with gray hairs (lighter in males to light silvery gray) and without distinct markings, abdomen brownish with slightly darker median longitudinal stripe, and venter blackish; usually builds burrow in ground; found throughout the United States.
- Rabidosa punctulata (Hentz). Adult female body length 7/16-5/8″ (11-17 mm), male 1/2-5/8″ (13-15 mm); color yellow with brownish to black longitudinal stripes, carapace (cephalothorax dorsum) with 2 submedial stripes, abdomen with 1 wide median stripe and 1 narrow lateral stripe in basal half on each side, and venter spotted; found in New England south to Florida and west to Rocky Mountains.
- Rabidosa rabida (Walckenaer). Adult female body length 5/8-7/8″ (16-21 mm), male about 7/16″ (11 mm); color yellow with brownish to black longitudinal stripes, carapace (cephalothorax dorsum) with 2 submedial stripes, abdomen with 1 wide median stripe enclosing lighter areas and 1 narrower lateral stripe solid in basal half and solid or as dots in apical/posterior half, venter not spotted, and male with 1st pair of legs dark brown to black; no burrow; found in New England to Florida and west to Oklahoma and Nebraska.
Biology of Wolf Spiders
The egg sac is spherical, consisting of an upper and lower half united at the middle. It is carried on the female’s spinnerets and is usually white, sometimes green, but changes to dirty gray or dirty brown with age.
In the New England states, Hogna carolinensis females lay their eggs in June and July. The egg sac is about 1/2″ (12 mm) in diameter contains about 100-135 eggs (range to 600 per sac). The mother bites open the egg sac allowing the enclosed spiderlings to emerge and crawl onto her abdomen where they stay for a week or longer; they usually emerge in June and July. They attain about half their growth by the succeeding winter and become adults the following year. Mating occurs in the autumn with males dying before winter. Females overwinter, lay their eggs the next May-June, and may live for a 3rd year.
In the New England states, Rabidosa rabida females lay their eggs in August to mid-October. The egg sac is about 5/16-3/8″ (7.5-10 mm) in diameter and contains 168-365 eggs. Upon emerging, the spiderlings crawl onto their mother’s body where they have been observed until mid-October. They become adults the following summer with mating occurring in August. Females live until frost.
Habits of Wolf Spiders
Wolf spiders actively hunt during the night and sometimes during the day. They are fast on their feet and pursue prey. Because of these habits, they are commonly seen by people. Wolf spiders often alarm people because they are big, hairy, and run fast.
Some wolf spider species build retreats consisting of either a shallow excavation under a stone, or a tube/burrow running vertically or diagonally into the ground. They leave their burrows primarily at night to hunt insect prey in the surrounding area. Some species build web retreats or shelters when with young, but they do not build snare webs.
Outside, they can be found under stones, landscape timbers, firewood, under decks, in leaf litter, etc. They often rest in such sheltered places during the day.
These spiders may enter structures in search of prey. Although they are not inclined to be permanent residents in structures, once inside, they often stay. Inside, they tend to stay at or near floor level, especially along walls under furniture and other objects. Wolf spiders may be brought indoors with firewood.
Control of Wolf Spiders
Follow the standard control procedures for spiders outlined in the introductory section. The use of glueboards indoors is quite effective when they are placed near where the spiders have been seen, along walls, under furniture or other objects, and/or near door thresholds.
What do Wolf Spiders look like?
Introduction to Tarantulas
The common name was applied by Europeans to the large, hairy spiders of the southwest and western United States probably because of the resemblance to a large European wolf spider that took its name from the city of Taranto in Italy. Myth was that people who thought they were bitten had a huge desire for dancing with the frenzied dance being referred to as “tarantism”, and the legend grew; the bite of that spider is no more dangerous than that of other wolf spiders. Although some people become alarmed when tarantulas are found indoors, they are primarily a nuisance pest; bites by United States species are no more harmful than a bee sting but they may shed hairs which cause itching. There are about 30 species found in the United States with most occurring in the south central states but more commonly in the southwestern states.
Recognition of Tarantulas
Adult female body length 1 3/4-2 7/8″ (43-70 mm) and a leg span of up to 5″ (130 mm), male body length about 1 9/16-2 9/16″ (40-65 mm); robust and very hairy. Color usually dark brown to blackish, sometimes tan to yellowish/reddish brown and/or with reddish golden hairs etc.; one species with dark spot on light-colored abdomen. Chelicerae (jaws) move vertically (vs jaws of all true spiders move horizontally) up and down so fangs move in plane almost parallel to median plane of body (=paraxial), front of body must be raised to plunge fangs downward; fang with distinct furrow/groove. Abdomen with 2 pairs of slit openings to booklungs (just to rear of 4th pair of legs) and anal tubercle immediately behind (above) 4 spinnerets. Tarsi each with 2 claws and claw tuft (bunch of hairs at tarsal tip).
Similar Groups to Tarantulas
(1) Purseweb spiders (Atypidae), foldingdoor trapdoor spiders (Antrodiaetidae) and sheetweb weaving atypical tarantulas (Mecicobothriidae) have abdomen usually with 1-3 sclerotized tergites (hard dorsal plates), cheliceral fang furrow indistinct, and anal tubercle separated from spinnerets by considerable distance.
(2) Trapdoor spiders (Ctenizidae) and sheetweb/funnelweb building tarantulas (Dipluridae) have tarsi with 2 large lateral and a small median claw, without claw tufts (pad of hairs).
(3) Wolf spiders (Lycosidae) with chelicerae diaxial (fangs move in transverse plane towards each other), and usually with only 1 pair of booklung slits just behind 4th pair of legs.
Representative Species of Tarantulas
- Aphonopelma chalcodes Chamberlin. Adult female body length about 2 7/8″ (70 mm) and leg span of about 5″ (130 mm), male body length about 2 9/16″ (65 mm); color dirty yellowish brown with abdomen, leg coxa-trochanter-femur, and 1st segment of pedipalps dark brown; found in Arizona.
- Aphonopelma eutylenum (Chamberlin). Adult female body length about 1 11/16″ (43 mm), male body length about 1 9/16″ (40 mm); color blackish to dark brown; found in California.
- Aphonopelma hentzi (Girard). Adult female body length 1 3/4-2 1/4″ (44-58 mm), male body length 1 1/4-2 1/16″ (32-52 mm); cephalothorax and legs dark brown with reddish golden hairs on carapace (cephalothorax dorsum), abdomen brownish black; found in southern Missouri and Kansas south through Oklahoma, Arkansas, and Louisiana.
Biology of Tarantulas
Mating occurs in the autumn, and the female produces an egg sac the following summer (July). The egg sacs average 800-850 eggs each, and are up to 2-3″ (50-75 mm) in diameter. After their first molt, young tarantulas venture out on their own. They molt about once each year and become adults in 5-7 years (some require 10-12 years). Adult males die about 6 months after reaching maturity. Adult females are very long-lived, often living in excess of 20 years. Adult females continue to mate once each year and produce an egg sac the following spring. They also continue to molt once each year during which any damaged palps and/or legs are replaced.
Tarantulas are not seriously toxic to humans. Their bites usually result in pinpricks with mild pain, but can be very painful because of the large chelicerae (fangs). However, the pain usually subsides in 30-60 minutes. Sensitive individuals may have more serious reactions, but serious injury or death is not likely to occur. Tarantulas are not aggressive and must usually be provoked to bite.
A physical encounter, such as handling a tarantula, may result in an itch. When disturbed, many tarantulas have the habit of rubbing off some of the hairs on the rear of their abdomen with the hind legs; this can result in a bald spot. These hairs are kinked and barbed such that they will cause irritation when they contact human skin. The allergic response to these hairs is likely to cause great discomfort.
Habits of Tarantulas
Tarantulas are nocturnal and spend most days secluded in their burrows or retreats. These are located in natural cavities in the ground, in old rodent burrows, under stones or debris on the ground, in cracks of trees, etc. They line the upper portion of their burrow with silk.
They usually hunt in the general area surrounding their burrow. Often, they may wait inside their burrow until a prey insect or spider gets close enough for capture. A number of tarantulas often occupy the same general area such as a hillside or pasture.
Females usually do not leave the vicinity of their burrows. However, males wander for considerable distances during the late summer and autumn (July to November) mating season in search of a mate. Sometimes males can be seen by the dozens wandering across roads and backyards.
As long as they have water, tarantulas can live for up to 2 years without eating. For pet tarantulas, crickets from the local pet store, bait shop, or yard are a good food.
Control of Tarantulas
Follow the standard control procedures outlined in the introductory spider section except pesticide application is almost never warranted. Sanitation to eliminate nearby burrows and exclusion are particularly important. Exclusion is important because tarantulas often enter structures through doors and unscreened windows left open at night or doors with wide gaps at the bottom.
Most calls are for single tarantulas which have entered structures. Capture in a box, remove, and release outside is the preferred method. Rarely is the application of pesticides required.
What do Tarantulas look like?
Introduction to Solpugids, Sun Spiders, Camel Spiders, Wind-Scorpions
The common names come from their order name, that of sun because they live in desert areas, because of their spiderlike or camel-like appearance, and because they can run extremely fast. There is confusion in the literature regarding calling these arthropods solpugids or solifuges; solpugids will be used in this Field Guide because of its more common usage. Of about 60 species of solifuges found in the arid aeas of the United States, 15 species are commonly found in the desert regions of southwestern United States, and one species, Ammotrechella stimpsoni (Putnam), occurs in Florida. Many more species are found in Latin America. Indoors, they are a nuisance pest.
Recognition of Solpugids, Sun Spiders, Camel Spiders, Wind-Scorpions
Adults up to about 1 3/4″ (45 mm) in length. Color tan, chelicerae dark, abdomen somewhat darker. Shape distinctive, body only slightly constricted behind cephalothorax (fused head and thorax), chelicerae very large (appear as 4 long, separate mandibles, a pair to either side, with curved tips and several teeth along their length), pedipalps long and leglike (used with 1st pair of legs as feelers), 4 pairs of legs present, 4th pair of legs with malleoli or racquet organs (stalked, “T”-shaped structures) on their ventral surfaces, and abdomen segmented with a wide rounded rear end, stinger absent.
Nymphs similar in appearance to adults, but legs appear longer because of smaller body size.
Similar Groups to Solpugids, Sun Spiders, Camel Spiders, Wind-Scorpions
(1) Scorpions (order Scorpiones) with large pincerlike pediplalps, segmented abdomen ending in a tail with apical stinger.
(2) Whipscorpions (order Uropygi) with pincerlike pedipalps, many with a long, thin whiplike tail that lacks a stinger.
(3) Pseudoscorpions (order Chelonethida) small (usually less than 3/16″ or 5 mm long), flat- tened, oval body with large clawlike pepipalps.
(4) Spiders (order Araneae) with abdomen strongly constricted at base, nearly always unsegmented, and with fingerlike spinnerets near its rear end.
(5) All other Arachnida, including 4 groups above, lack malleoli or racquet organs on 4th pair of legs.
Biology of Solpugids, Sun Spiders, Camel Spiders, Wind-Scorpions
This group has been poorly studied, so very little is known. Burrows are utilized for protection from temperature extremes and predators. During mating, the sperm are transferred either on the male’s chelicerae or in a spermatophore that is placed in the female’s genital opening with the male’s clelicerae; some species are capable of multiple matings. Eggs are laid in mass about 11 days after mating, with some species laying more than one batch. They may be placed in the ground or in an earthen birth chamber and they may be guarded by the female. Incubation varies from 2 days to 2 months depending on temperature and humidity. The first stage after hatching is called a larva or post-embryo. They have poorly developed appendages and are rather immobile. In a few days, they molt into first instars that resemble adults in appearance, but are smaller. They are gregarious and remain in the birth chamber. With the next molt into the second instar, they disperse. Some species have only one generation per year, while others have two. Males tend to die shortly after mating. Adults live less than one year.
Habits of Solpugids, Sun Spiders, Camel Spiders, Wind-Scorpions
Solpugids as a group are poorly studied. They are one of the dominant predators of arid ecosystems. They have a voracious appetite. In turn, birds, small mammals, reptiles and arachnids eat them.
Most species spend their days in their sub-surface burrows or under soil-surface debris to escape the hot temperatures; only 5 or 6 species in the genus Hemerotrecha are diurnal. The Florida species, Ammotrechella stimpsoni, is known to inhabit above-surface habitats such as termite and other wood-boring insect tunnels.
Most species come out and hunt at night. Solpugids feed on a wide variety of prey, from termites to small vertebrates, but mostly on arachnids. They are very agile and have been observed by the senior author to cover many feet in just a few seconds on a mid-summer night in Arizona.
They eat by macerating their prey in their massive chelicerae. They then extract and consume the liquids.
Solifuge species are typically isolated seasonally. The abundance of mature adults peaks for different species at different times, typically during a short time period of a few weeks anywhere from January through December, but mostly March through October. Species are also isolated by different habitat preferences.
Control of Solpugids, Sun Spiders, Camel Spiders, Wind-Scorpions
Since these are beneficial arthropods, control measures are not desirable. If found indoors, they should be relocated to the outside, or if necessary, they can be removed with a vacuum.
Outside, removal of attractive habitat is best. That is, eliminate or reduce yard debris, woodpiles, stones and rock piles, or anything that would provide shelter from the hot daytime sun. This is especially important within 30 ft (9 m) of the structure. Also, proper light management is necessary to reduce the number of insects that the lights attract. Change mercury vapor lights to sodium vapor, and white incandescent and florescent bulbs to yellow bulbs. Locating a decoy mercury vapor light over 50 ft (15 m) away from the structure may help. On the structure itself, practice exclusion. This includes doors and windows should be tight-fitting, door sweeps in good repair, door and window frames sealed, windows screened and the screen in good repair, and all utility lines and other wall penetrations sealed. Also, all vegetation should be trimmed back so that none is in contact with the structure.
What do Solpugids, Sun Spiders, Camel Spiders, Wind-Scorpions look like?
Introduction to the Field Cricket
Field crickets can severely damage or destroy field crops and vegetable crops and hence, probably get their common name from this activity. The genus Gryllus is widely distributed throughout the Americas or New World, and consists of about 25 species in the United States.
Recognition of the Field Cricket
Adults 1/2-1 1/8″ (13-30 mm) long. Color typically black but varies to brownish yellow or straw yellow. Antenna threadlike, much longer than body. Wings lay flat on the back. Adults may be short-winged (hindwings completely concealed by front wings) or long-winged (hind wings protruding from beneath front wings to form “tails”); some species contain both wing morphs. Cerci long, feelerlike. Hind leg tibial spines short, stout, non-movable. Tarsi 3-segmented. Adult female with a long tubelike ovipositor (egg laying structure) located at tip of abdomen, between cerci.
Nymphs similar to adults except smaller, and lack wings and an ovipositor (females).
Similar Groups to the Field Cricket
(1) House crickets (Acheta domesticus) are light yellowish brown with 3 dark crossbands on head.
(2) Cave/camel/stone crickets (Gryllacrididae) with humpbacked appearance, wingless, antennae touch or almost touch at base, hind femora long.
(3) Jerusalem crickets (Stenopelmatidae) large and robust, wingless, hind femora do not extend beyond tip of abdomen.
(4) Mole crickets (Gryllotalpidae) with front legs broad and spadelike, antennae much shorter than body length.
(5) Earwigs (order Dermaptera) with forcepslike cerci.
Biology of the Field Cricket
Field crickets usually overwinter in the egg stage but depending on the species, may overwinter as mid- to late-instar nymphs. The females usually lay 150-400 eggs which are deposited singly in firm but moist soil. There are typically 8 (males) to 9 (females) instars which require 78-90 days (range 65-102) to mature. There may be 1-3 generations per year.
Habits of the Field Cricket
Outdoors around buildings, they are typically found in moist situations such as in mulched areas, unweeded plant beds, in and around woodpiles, stones, and debris, etc. Their presence is often indicated by the male’s chirping, which for most species occurs during the day and night. These sounds are made by rubbing the front wings together. His “calling song” serves to attract females. They are often attracted in great numbers to electric lights.
Field crickets can destroy field crops such as alfalfa, wheat, oats, and rye, and vegetable crops such as tomatoes, cucumbers, peas, beans, etc. Huge outbreaks occasionally occur in the midwest and south where they sometimes enter towns and cities in great swarms. They also feed on other insects and their own kind.
They do not survive indoors for long periods of time and usually die off by winter. However, they may cause damage to fabrics of cotton, wool, linen, silk, synthetics, or leather and fur garments, especially when soiled with perspiration or food.
Control of the Field Cricket
Cricket control starts outdoors with the reduction or elimination of moist harborage near the structure by mowing lawns, weeding plant beds, removing woodpiles, etc. Since they are attracted to lights, change outdoor lighting to less-attractive yellow bulbs or sodium vapor lamps. Seal possible points of entry such as around windows and doors, holes in masonry, add doorsweeps, and screen windows, doors, etc.
Baits are especially effective when applied as a band between the structure and peripheral harborages or indoors. Microencapsulated or wettable powder formulations are particularly effective in the moist areas that crickets prefer. Mechanical removal with a vacuum works well. Crack and crevice treatment may be required indoors for infestations.
What does a Field Cricket look like?
Introduction to the House Cricket
The common name comes from the fact that these crickets often enter houses where they can survive indefinitely. Having been introduced from Europe, this species is found throughout the United States but is a pest primarily east of the Rocky Mountains.
Recognition of the House Cricket
Adults about 3/4-7/8″ (16-22 mm) long. Color light yellowish brown with 3 dark crossbands on head. Antenna threadlike, longer than body. Wings lay flat on the back. Cerci long, feelerlike. Hind leg tibial spines short, stout, non-movable. Tarsi 3- segmented. Adult female with a long tubelike oviposter (egg laying structure) located at tip of abdomen and between cerci.
Nymphs look like adults except smaller, and lack wings and an ovipositor (females).
Similar Groups to the House Cricket
(1) Field crickets (Gryllus spp.) lack crossbands on top of head.
(2) Cave/camel/stone crickets (Gryllacrididae) with humpbacked appearance, wingless, antennae touch or almost touch at base, hind femora long.
(3) Jerusalem crickets (Stenopelmatidae) large and robust, wingless, hind femora do not extend beyond tip of abdomen.
(4) Mole crickets (Gryllotalpidae) with front legs broad and spadelike, antennae much shorter than body length.
(5) Earwigs (order Dermaptera) with forcepslike cerci.
Damage Caused by the House Cricket
House crickets typically surface feed, leaving the surface roughened from pulling or picking the fibers loose while feeding. Their feeding sometimes results in an irregular matted network over the surface, or if the infestation is heavy, large areas of the fabric may be eaten out. Mandible marks along the chewed edges are often visible but only with magnification. Such marks are much less than 1/32″/1 mm wide, not in pairs, and with little or no tearing. Fecal stains are absent but with fecal pellets on or about the damaged materials. The larger fecal pellets are about 1/16″-1/8″ (2-2.5 mm) long and about 1/32″ (1 mm) wide, with the pellets almost or entirely lacking longitudinal ridges. No hairs are on or about the damaged materials.
Biology of the House Cricket
Outdoors, the overwintering eggs hatch in late spring and adults appear in late summer, with only 1 generation per year. When raised under ideal conditions, females lay an average of 728 eggs. The nymphs go through 7-8 instars which require an average of about 56 days for males and 53 days for females. Indoors, females deposit an average of 104 eggs (range 40-170) at room temperature. Their eggs are placed singly in crevices, such as behind baseboards and other dark places.
Habits of the House Cricket
During warm weather, house crickets typically live outdoors and especially in garbage dumps. With the approach of cold weather, they seek sheltered places such as sheds and houses.
These crickets are nocturnal or active at night and usually hide in dark warm places during the day. Their presence is indicated by the male’s chirping which is done by rubbing their front wings together. His “calling song” serves to attract females.
Outside, they are often attracted to electric lights in large numbers, sometimes by the thousands, and rest on vertical surfaces such as light poles and house walls. Outside, they feed on plants and dead or live insects, including crickets.
They often enter homes seeking moisture. When these crickets enter homes, many kinds of clothing and even carpets can be damaged. Favorite fabrics include wool, cotton, silk, and synthetics (particularly acetate, vicose, and triacetate). Clothes soiled with perspiration are especially attractive to crickets. They eat out large areas of fabrics as opposed to the small holes typical of clothes moths.
Control of the House Cricket
Cricket control starts outdoors with the reduction or elimination of moist harborage near the structure by mowing lawns, weeding plant beds, removing woodpiles, etc. Since they are attracted to lights, change outdoor lighting to less-attractive yellow bulbs or sodium vapor lamps. Seal possible points of entry such as around windows and doors, holes in masonry, add doorsweeps, and screen windows, doors, etc.
Baits are effective when applied as a band between the structure and peripheral harborages or indoors. Microencapsulated or wettable powder formulations are particularly effective in the moist areas that crickets prefer. Mechanical removal with a vacuum works well. Crack and crevice treatment of possible entry points may reduce invasion or may be required indoors for established infestations.
What does the House Cricket look like?
Introduction to Western Drywood Termites
The common name refers to its western United States distribution and to the fact that it lives in wood that has a relatively low moisture content (12% or less). It is found in the southwestern United States, up the west coast of California with spotty infestations in Oregon and Washington, southward into northwestern Mexico, in the central valley of California and extends eastward into central and southern Arizona. In the east, there are spotty infestations in New York, New Jersey, Maryland, South Carolina, Georgia, along both coasts of Florida, in Louisiana and Texas. Inland structural infestations occur in Utah, Oklahoma, Arkansas, Iowa, Minnesota, Wisconsin, Ohio, and Pennsylvania. It is also found in the Caribbean and has been introducted into southern Japan. However, it can readily be transported outside its natural areas in infested furniture, picture frames, etc., and on yachts, sailboats, and small pleasure craft. Such transport has resulted in small localized individual structural infestations in several places in the United States and Canada.
Recognition of Western Drywood Termites
Swarmer. About 7/16-1/2″ (11-12.5 mm) long including wings, wings 3/8″ (8.5 mm) or longer. Head and pronotum orange brown, abdomen dark brown, and wing membrane with smoky tinge and sclerotized (hardened or pigmented) veins blackish. Head with 2 ocelli; with hairs shorter than diameter of eye. Antenna with 10-11 segments, 3rd segment slightly longer and darker than adjacent segments. Front wing with 3 dark, heavily sclerotized veins in front half/portion; median vein (M) unsclerotized, running midway between sclerotized veins above and unsclerotized cubitus (Cu) below, and curving forward near mid-wing to join sclerotized radial sector vein (Rs); and a few sclerotized diagonal cross veins branch to coastal margin; not hairy. Tibia with spines absent along length, apex with 3 spines; tarsi with arolium (pad) absent between claws.
Soldier. Large, about 5/16-1/2″ (8-12+ mm) long. Forehead slopes down gradually from top of head, head flattened to slightly rounded in side view, and head orange to reddish brown with eye spot whitish. Mandibles with unequal number of teeth on each member of pair; left mandible with 2 distinct teeth on its inner margin. Antenna with 3rd segment greatly enlarged and clublike, as long as or longer than segments 4-6 combined, and about twice as wide as 4th segment. Pronotum as wide as or wider than head (dorsal view).
Similar Groups to Western Drywood Termites
(1) Other structure-infesting drywood termites (Incisitermes spp.) with swarmer wing membrane uncolored or faintly yellowish brown, and front wing with unsclerotized median vein (M) ending near tip of wing; soldier with 3rd antennal segment shorter than segments 4-6 combined and less than twice width of 4th segment.
(2) Dark southeastern drywood termite (Kalotermes approximatus) with swarmer shorter (3/8″/8.5- 10 mm) including wings, with head, thorax, and abdomen dark reddish brown, hairs on head longer than diameter of eye, front wing with numerous sclerotized diagonal cross veins, and tarsi with arolium (pad) present between claws; soldier with 3rd antennal segment shorter than segments 4-6 combined and less than twice width of 4th segment.
(3) Formosan subterranean termite (Coptotermes formosanus) swarmer has wings densely covered with hairs; soldier with mandibles lacking teeth.
Damage and Signs of Infestation of the Western Drywood Termite
Drywood termites eat across the wood grain and make chambers and/or galleries connected by tunnels. Their gallery and tunnel walls are velvety smooth, and no soil is present. Usually there are fecal pellets present which are hard, less than 1/32″ (average 0.98 mm) long, elongate-oval with rounded ends, and have 6 concave sides. Signs of infestation include swarmers, shed wings, piles of pellets, termite plugs which seal all openings in infested wood, and surface blisters caused by older enlarged galleries very close to the wood surface.
Damage to wood occurs slowly. Under optimal conditions of 80-90°F (26-32°C) and 50% relative humidity, it has been estimated that one drywood termite eats about 0.59 mg of wood per day. Therefore, a colony of 1,000 mature nymphs would consume about 1/2 pound (0.25 kg) of wood in a year. Be aware that it would take a drywood colony about 7+ years to reach this size. Swarmers often reinfest the same structure.
Annual damage and treatment costs in California and Arizona are estimated (2006) to be $250 million.
Biology of the Western Drywood Termite
Drywood termites are non-subterranean termites; they do not live in the ground, require no ground contact, and do not build mud tubes.
Their colonies are located in the wood they eat and are of small size when compared to subterranean termite colonies, usually numbering less than 3,000 individuals after 15 years. There is no worker caste and the immatures/nymphs perform all tasks typically done by workers.
The life history of the western drywood can be briefly summarized as follows. After flight, they seek cracks, nail holes, or knotholes in nearby wood and gnaw a small tunnel that they close; here, they excavate a chamber or cell after which they mate. The pair may remain dormant for nearly a year or produce up to 5 eggs, 20 nymphs, and 1 soldier. By the end of the 2nd year, the colony may consist of 6-40 nymphs, and 1 soldier. After 3 years, the colony may consist of 40-165 individuals, and 70-700 individuals after 4 years; such colonies have a soldier to nymph ratio of 1:15 to 1:60. The nymphs go through 4-7 instars, with reproductives requiring 7. The first swarmers may be released when the colony is 4 years old.
Swarming typically takes place about midday on sunny, warm (80-100°F/26.7-37.8°C) days, with the peak of the swarm occurring after a sudden rise in temperature. In southern California, it typically occurs from September through November, but in desert areas such as Palm Springs, it swarms as early as May. In Florida, swarming occurs during every month except December, but mostly in September, October, and November. Swarmers usually number in the dozens, occasionally the hundreds. They are weak fliers, the strongest traveling only up to 250 feet (76.2 m) from their point of emergence.
Habits of the Western Drywood Termite
Swarming drywood termites fly into structures and infest wood directly. When swarming, they often reinfest the same structure. They typically first infest exposed wood such as window/door frames, trim, eaves, attics, etc. They do so by finding a protected crevice or other area, such as the joint between 2 pieces of wood, where shingles/paper overhang timber or molding, etc., and then attack the wood. On roofs, they tend to avoid wooden shingles because the temperatures are too high. However, they are commonly found in attics where temperatures may exceed 131°F (55°C). Here they locate their colonies in wood with more favorable temperatures, such as ceiling joists that have their bottom sides cooled by the A/C below and modulated by surrounding insulation. It may take 5-7 years before a new colony produces visible damage.
Drywood termites are often distributed by human activity, commonly by transporting infested furniture, picture frames, boats of various types, and wood to new areas. The western drywood termite has been found in localized structural infestations in such places as St. George, Utah, Milwaukee, Wisconsin, Cleveland, Ohio, Niagara Falls, New York, Pittsburg, Pennsylvania, Fegus Falls, Minnesota, Toronto, Canada, etc., but it has failed to become established and spread in such areas outside its normal southern and mostly coastal range.
Control of the Western Drywood Termite
Since infestation is direct and not via the ground, the most successful methods of control are fumigation, or local treatment or replacement of the infested wood. Fumigation is recommended if infestations are widespread and/or difficult to access whereas, local treatment with pesticides or other means is prudent where infestations are isolated and accessible.
If the infestation is confined to a piece of furniture, picture frame, etc. which can easily be removed, then it may be treated via heat or cold if practical, or the infested item destroyed. Other methods/means available include the use of microwaves, the application of electrical currents (high watts, low amps), etc.
Localized infestations may be treated via intergallery injection or surface treatment with pesticides which are labeled for these termites.
What do Western Drywood Termites look like?
Introduction to the Desert Subterranean Termite
The common name reflects its southwestern United States distribution, where it is almost entirely restricted to the Colorado and Gila deserts of southern Arizona and California and into Lower/Baja California. It lives in desert plants including dead cactus, but can severely damage posts, utility poles, and the wood of buildings.
Recognition of the Desert Subterranean Termite
Swarmer. About 3/8″ (10 mm) long including wings. Body pale yellowish to pale yellowish brown. Fontanelle (front gland pore) indistinct or absent. Wing with 2 prominent but lightly pigmented, heavily sclerotized (hardened) veins in front portion, other veins unpigmented except for basal third. Wing membrane translucent, almost colorless, with a few barely visible hairs. Front wing scale distinctly larger than hind wing scale, may overlap basal portion of hind wing scale. Ocelli conspicuous but not large. Antenna with less than 18 segments.
Soldier. Head rectangular in shape, not narrowed toward front, length about 2x width. Fontanelle (front gland pore) dorsal. Mandibles very slender, fairly straight but slightly curved inward at tip (about 15°), acutely pointed, and usually longer than head width; lack teeth. Pronotum flat, almost as wide as head.
Similar Groups to the Desert Subterranean Termite
(1) Reticulitermes tibialis and western subterranean termite (R. hesperus) swarmers dark brown to black; soldier with mandibles not quite as long as head width, usually somewhat roughened, not slender, and distinctly curved inward at tip (about 45°).
(2) Formosan subterranean termite (Coptotermes formosanus) swarmer with wing densely covered with hairs; soldier with head tapered towards front and fontanelle opening at end of short, forward-facing tube on front margin of head.
(3) Amitermes spp. and Gnathamitermes spp. swarmers brown to black; soldiers with a single tooth on each mandible.
Damage and Signs of Infestation of the Desert Subterranean Termite
Subterranean termites eat mostly the spring wood, which they prefer over the harder summer wood. Hence, damaged wood appears to be layered. Sometimes soil is present in the galleries.
This species is apparently less dependent on moisture and decay than other subterranean termites. It readily attacks dry, sound wood. A typical sign of infestation is the presence of drop tubes coming from the ceiling rafters and sheetrock/plasterboard and/or holes in the sheetrock plugged with feces. Also, their mud tubes are light in color (yellowish white to tan) and almost circular in cross section.
Biology of the Desert Subterranean Termite
Very little has been published on the biology of this species. Its biology is thought to be similar to that of the western subterranean termite, Reticulitermes hesperus Banks.
The desert subterranean termite swarms at night. After swarming, they pair off, enter the soil, and excavate a cell. Mature colony size in their natural habitat is typically about 150,000 workers, with a range of 45,000-300,000 workers. Each colony contains large numbers of secondary queens. They can form secondary colonies when their ground connection is interrupted, with secondary reproductives being produced in about 6 weeks.
A colony’s foraging territory in the natural habitat can range from a few hundred square yards to several thousand square yards, with a maximum of 35,508 sq ft/0.8 acre (3,300 sq m/0.3 hectare). Workers have been found to forage up to 223 ft (68 m) in 11 days.
Habits of the Desert Subterranean Termite
The colonies are typically located in the desert soil. They readily build mud tubes to transverse inpenetrable materials or adverse conditions to reach wood. Their tubes are smaller, more solidly built, lighter in color (yellowish white to tan), and more circular in cross section than those of Reticulitermes spp. which are flattened in cross section and a dirty light brown. Desert subterranean termites require a hole of only about 1/32″ (1 mm) in diameter for access. They often build tubes from the ground up underneath buildings, with these tubes often 24+” (60.9+ cm) in height. Within structures, they often construct drop tubes from ceilings and other overhead places.
These termites are often attracted to the thermal shadows that are cast by various objects such as rocks/stones, animal dung, plants, and structures. These thermal shadows provide areas of soil with cooler temperatures. Foraging is greatest during the summer rainy season, but they tend to forage year round in areas of denser vegetation. Such areas provide higher moisture, lower temperature, and a food supply.
Control of the Desert Subterranean Termite
This is similar to that for other subterranean termites. It involves placing a chemical treatment zone (second-generation nonrepellent pesticides work best) and/or an in-ground perimeter monitoring-baiting system between the termite colony and the wood of the structure. In addition, all wood-to-soil contact should be eliminated (the building owner’s responsibility) and any wood debris must be removed. Secondary colonies are controlled by correcting the moisture problem to dry out the moisture-source area. When it is desirable to rapidly reduce the secondary infestation, this can be done by treating the galleries with an appropriately labeled pesticide. Also available are above-ground termite baiting systems that are placed directly on the infested wood.
What does the Desert Subterranean Termite look like?
Introduction to the Western Subterranean Termite
This species is restricted to the western states, ranging from British Columbia south to western Mexico and east to Idaho and Nevada.
Recognition of the Western Subterranean Termite
Swarmer. About 3/8″ (9 mm) long including wings. Body dark brown to almost black. Fontanelle (frontal gland pore) present, may be inconspicuous. Front wing with 2 dark, heavily sclerotized (hardened) veins in front portion, other veins unpigmented except for basal third. Wing brownish gray, with a few barely visible hairs. Front wing scale distinctly larger than hind wing scale, may overlap basal portion of hind wing scale. Leg with tibia slightly darkened, tarsus pale.
Soldier. Head rectangular in shape, not narrowed toward front, length fully 2 times width. Fontanelle (frontal gland pore) dorsal. Mandibles lack teeth. Pronotum flat, almost as wide as head.
Similar Groups to the Western Subterranean Termite
(1) R. tibialis swarmer with wings whitish, almost colorless and tibiae black to sooty (vs pale tibiae).
(2) Eastern subterranean termite (R. flavipes) swarmer with wings sooty and tibiae and tarsi pale; soldier with head less than twice as long as broad.
(3) Desert subterranean termite (Heterotermes aureus) swarmer pale yellowish brown with wings almost colorless; soldier with mandibles slightly longer than head width, smooth and slender.
(4) Formosan subterranean termite (Coptotermes formosanus) swarmer has wings densely covered with hairs and body pale to brownish yellow; soldier with head rounded on sides and tapered toward front, with fontanelle (pore opening) on slight tubercle (very short tube) toward front of head.
(5) Most other termite swarmers likely to be in western states have 3 or more pigmented veins in front wings.
Western Subterranean Termite Damage
This is the same as for the eastern subterranean termite. They eat mostly the spring wood and leave the lignin-containing summer wood which they cannot effectively digest. Hence, damaged wood appears to be layered. Also, soil is typically found in the galleries.
Biology of the Western Subterranean Termite
The biology of the western subterranean termite is very similar to that of the eastern subterranean termite. After swarming, they pair off and construct an appropriate cavity. They mate within a day of excavating their cavity. An average of 10 eggs is produced in the 1st clutch (range 4-20). The eggs usually hatch in 50-56 days (range 30- 90). The 1st instar lasts 14-18 days, the 2nd lasts 14-18 days, the 3rd about 30 days, the 4th about 60 days. There may be as many as 7 instars. Development usually takes more than 5 months and workers may live from 3-5 years. Swarmers are not produced before the 3rd or 4th year, at the earliest.
Swarming takes place during the daytime. In the northern part of its range, swarming takes place in the spring, but without rain. In the southern portion of its range, swarming usually follows rain. In some areas, fall swarms are very large.
The estimated foraging area for this termite species is 82-3,780 sq ft (25-1,152 sq m).
Habits of the Western Subterranean Termite
These are essentially the same as for the eastern subterranean termites. The colonies are usually located in the ground. Location is usually below the frost line, but above the water table and rock formations. Mud tubes are built to cross areas of adverse conditions between the colony and food sources. They can enter structures through cracks less than 1/16″ (1-2 mm) wide. However, if a constant source of moisture is available (like leaky pipes), colonies (called secondary colonies) can exist above ground and without ground contact.
Control of the Western Subterranean Termite
This is the same as for the eastern subterranean termite. It involves placing a chemical treatment zone (second-generation nonrepellent pesticides work best) and/or an in-ground monitoring-baiting system between the termite colony and the wood of the structure. In addition, all wood-to-soil contact should be eliminated, any wood debris must be removed, and the wood moisture content should be reduced to below 20%. Secondary colonies are controlled by correcting the moisture problem to dry out the moisture-source area. When it is desirable to rapidly reduce the secondary infestation, this can be done by intergallery injection or surface treatment with a pesticide labeled for these termites. Also available are above-ground baiting systems that are placed directly on the infested wood.
What does the Western Subterranean Termite look like?
Introduction to the House Mouse
The house mouse is the most commonly encountered and economically important of the commensal rodents, the Norway and roof/black rats being the other two. House mice are not only a nuisance, damage/destroy materials by gnawing, and eat and contaminate stored food, they are also of human health importance as disease carriers or vectors. It is thought to be of Central Asian origin, but is now of worldwide distribution and found throughout the United States.
Recognition of the House Mouse
Adult with head and body length 2.5-3.75″ (6.5-9.5 cm), tail length 2.75-4″ (7-10.2 cm), weight about 0.5-1.1 oz (12-30 g). Fur smooth, color usually dusty gray above and light gray or cream on belly (some mice light brown to dark gray above), but fur color varies considerably from area to area or location to location regardless of living habits. With muzzle pointed, eyes small, incisors ungrooved, ears large with some hair. Feet short and broad. With a uniformly dark, scaly, semi-naked tail. Adult droppings 1/8-1/4″ (3-6 mm) long, rod-shaped, with pointed ends, and lack ridges (American cockroach droppings with ridges).
Signs of Infestation of the House Mouse
- Gnaw marks. New gnawings or holes tend to be rough whereas, old gnawings are smooth from wear.
- Droppings. Fresh droppings are soft and moist whereas, old droppings are dried and hard; house mouse’s about 1/8-1/4″ (3-6 mm) long, rod shaped, and with pointed ends vs American cockroach about 1/8″ (3 mm) long and with ridges.
- Tracks/footprints. Front foot 4-toed and print is in front of hind print with 5-toes. Fresh tracks are clear and sharp whereas, old tracks are at least partially obscured by dust.
- Rub marks. These are usually less noticeable and smaller in size than those of rats.
- Burrows. Indoors they often nest in various materials such as insulation. If active, free of dust and cobwebs. Entrance usually with material packed/compressed, rub marks sometimes visible.
- Runways. Frequently use the same paths, usually along walls, stacked merchandise, etc., and to interior objects. Active runways free of dust and cobwebs, with fresh droppings. Tracks may or may not be visible.
- Damaged goods. Mice prefer seeds or cereals, but will readily eat insects trapped on glue boards, leaving only some legs and antennae.
Similar Groups to the House Mouse
(1) Adult Norway (Rattus norvegicus) and roof/black (R. rattus) rats with body and head length 7-9.5″ (18-25 cm) and weigh 7-18+ oz (200-500+ g).
(2) Young Norway and roof/black rats with head and feet disproportionately large for body size.
(3) Deer mouse (Peromyscus maniculatus) and white-footed mouse (P. leucopus) very similar in size and weight but with distinct bicolored tail (tawny brown above, white underneath), a distinct line evident where 2 colors meet, seed feeders.
(4) Most other native rats and mice with hairy tail, hairs short or long, or if tail almost naked, it is also annulate (appears to be of ringlike segments).
Biology of the House Mouse
The house mouse is a prolific breeder. They reach sexual maturity in 35 days and mate when 6-10 weeks old. Pregnancy lasts an average of 19 days (range 18- 21). The young are blind and naked except for vibrissae (long whiskers), and are weaned at about 21 days (range 3-4 weeks). The average litter size is 6 (range 5-8), with about 8 litters per year, but averaging 30-35 weaned/female/year. Therefore, a female can have a new litter about once every 40-50 days. More than 1 litter may be present in the nest at one time. Life expectancy is normally less than 1 year, but mice have been known to live as long as 6 years.
Mice have keen senses, except for sight because they cannot see clearly beyond 6″ (15 cm) and are color blind. They are excellent climbers and can run up most roughened walls. Mice can swim but prefer not to do so. They can jump 12″ (30.5 cm) high and can jump down from about 8 ft (2.5 m) high without injury. Mice can survive and thrive in cold storage facilities at 14°F (-10°C). They can run horizontally along pipes, ropes, and wires. A mouse requires about 1/10 oz (2.8 g) of dry food and 1/20 oz (1.5 ml) of water (normally obtained from food) each day and produces about 50 droppings each day.
Over a 6-month period, a pair of mice will eat about 4 pounds (1.8 kg) of food, produce about 18,000 droppings, and void about 3/4 pint/12 oz. (355 ml) of urine.
The most common way mice transmit disease organisms is by contaminating food with their droppings and/or urine.
The most threatening organism spread by mice is Salmonella, a cause of food poisoning, spread via droppings. Other transmittable organisms include tapeworms via droppings, rat-bite fever via bites, infectious jaundice/leptospirosis/Weil’s Disease via urine in food or water, a fungus disease (Favus) of the scalp either by direct contact or indirectly via cats, plague and murine typhus via fleas, Rickettsial pox via the mite Liponyssoides sanguineus (Hirst), lymphocytic choriomeningitis via droppings, and possibly poliomyelitis (polio). Another problem is house mouse mite dermatitis which is caused by these mites when they feed on humans.
Habits of the House Mouse
Mice are very social. Related males and females are compatible, but unrelated male mice are typically very aggressive toward one another. Social hierarchies with one male dominating lower-ranking males result in the maintenance of territories, which may include a large number of females as well as lower-ranking males, most of which will be related. All mature mice tend to show aggression towards strangers of either sex that enter their territory, which is marked with urine. Territory size varies but it is usually relatively small. If food and shelter are plentiful, they may not travel more than 4-5 feet (1.2-1.5 m) from their nests.
Mice are inquisitive. During the daily territorial patrol, they will explore anything new or changed, and establish new travel routes if needed. Mice are nibblers and eat only small amounts of food at any one time or place. Although mice will eat many kinds of food, seeds and insects are usually preferred. They are opportunistic feeders and should one food disappear, they will readily switch to another food. There are 2 main feeding periods, at dusk and just before dawn, with many other “mini” feeding times in between. They will sample new foods but return to the old food unless the new food is preferred. Required moisture is normally obtained from their food but they will take free water when available, especially when feeding on high-protein food. When given a choice, they prefer sweetened liquids over plain water.
Their preferred nesting sites are dark, secluded places where there is abundant nesting material nearby and little chance of disturbance. Nesting materials include paper products, cotton, packing materials, wall/attic insulation, fabrics, etc. Mice are nocturnal in habit. They require an opening of greater than 1/4″ (6 mm) to gain entry.
In rural and suburban areas, the house mouse lives outdoors in wooded areas, fields, croplands, yards, etc., where they build their nest in vegetative debris, natural cavities, burrows, etc. Here they feed on seeds and insects. Since the house mouse cannot hibernate, in temperate areas they seek shelter as the weather cools and their food sources disappear. Around structures, they follow warm air currents and food odors coming out through door thresholds, utility line entrances, etc. into a suitable site. If the entrance has been marked by previous mice, it’s just that much more attractive. In urban areas, they commonly come in from other structures via utility connections, or from other parts of the same structure. In commercial structures, mice are commonly also brought in with supplies and/or equipment.
Control of the House Mouse
The key to any mouse control program is pest identification, sanitation, harborage elimination, and mouse-proofing the building. Control is based on the behavioral habits of mice. Some of the most important things to remember are:
- Mice defecate wherever they travel but mostly where they feed. Mouse droppings serve to indicate where control efforts should be concentrated. Non-toxic tracking powders can also be used to determine where the greatest mouse activity is occurring.
- Territories are relatively small and rarely exceed 20 ft (6 m) in diameter. Traps and bait stations must be placed within this area if control is to be effective. If a trap or bait is unused after 48 hours, move it because the mice are elsewhere.
- Mice are nibblers. Put a little bit of bait in many bait stations to increase exposure and consumption. Change baits until preference is established, then utilize this bait until feeding stops.
- Mice are inquisitive. Move things around when traps/stations/glue boards are introduced so mice will explore to establish new movement routes. This makes trapping/baiting more successful.
- Mice like nesting material nearby. Use nesting material on the trigger of snap traps and in the center of glue boards.
- Water requirements increase with temperature and/or a lower moisture content of food. Use water baits (sweetened with prune juice, pineapple juice, or original cherry flavor Kool-Aid) during hot weather and when food moisture content may be low, e.g., feed and grain elevators, warehouses, etc.
- Mice are attracted to certain foods. Bait snap traps and/or the center of glue boards with prunes, fresh pineapple, salted peanuts, or whatever they are feeding on at the time. Tie the bait down on the trigger with unsented/flavored dental floss.
- Glue boards tend to harvest only juveniles and the occasional adult; adults typically jump over them. Use multiple-catch traps in addition to glue boards.
- Traps and bait stations are more effective if placed in corners (mice slow down for corners), and along established runways. Droppings will indicate the best placement sites.
- Outdoors, reproduction is more seasonal, hitting its low between October and January. Because of a reduced chance of introductions, concentrated control efforts should be more effective in eliminating the mice during this low period.
What does the House Mouse look like?
Introduction to the Sewer Rat (Norway/Brown/Wharf Rat)
The Norway rat is the largest of the commensal rodents and the most common commensal rat in the temperate regions of the world. It not only damages/destroys materials by gnawing, eats and contaminates stored food, but it is also of human health importance as a vector or carrier of diseases. It is thought to be of central Asian origin, but is now of worldwide distribution and found throughout the United States.
Recognition of the Sewer Rat (Norway/Brown/Wharf Rat)
Adult with combined head and body length 7-9.5″ (18-25 cm), tail length 6-8″ (15-21 cm), usual weight about 7-18 oz (200-500 g) but up to 20.5 oz (620 g). Fur coarse, shaggy, brown with scattered black hairs, with underside gray to yellowish white. With muzzle blunt, eyes small, ears small (do not reach eyes) and densely covered with short hairs. Heavy bodied. With scaly tail bicolored (darker above), shorter than head and body combined. Adult droppings up to 3/4″ (20 mm) long, capsule-shaped with blunt ends.
Signs of Infestation of the Sewer Rat (Norway/Brown/Wharf Rat)
- Gnaw marks. New gnawings or holes tend to be rough whereas, old gnawings are smooth from wear and old holes are often greasy.
- Droppings. Fresh droppings are soft and moist whereas, old droppings are dried and hard; adult Norway’s about 3/4″ (18-20 mm) with blunt ends vs. adult roof’s about 1/2″ (12-13 mm) with pointed ends.
- Tracks/footprints. Front foot 4-toed and print is in front of usually longer hind print with 5 toes. Fresh tracks are clear and sharp whereas, old tracks are at least partially obscured by dust.
- Rub marks or dark, greasy markings on vertical surfaces. Fresh marks are soft, greasy, and easily smeared whereas, old marks are with the grease dry and flaky.
- Burrows. Found in earthen banks, under concrete slabs, and under walls. If active, free of dust and cobwebs. Main opening usually with hard packed soil, rub marks may be visible.
- Runways. Consistently follow same paths, usually along walls, stacked merchandise, etc. Active runways with greasy appearance, free of dust and cobwebs, with fresh tracks and/or droppings.
- Damaged goods. Norway rats prefer meat, fish, and cereal (dry dog food a favorite) whereas, roof rats prefer fruits, vegetables, and cereals.
Similar Groups to the Sewer Rat (Norway/Brown/Wharf Rat)
(1) Roof rat (Rattus rattus) with muzzle pointed, eyes large, ears large, almost naked tail uniformly colored and longer than head plus body, droppings spindle-shaped with pointed ends.
(2) Hispid cotton rat (Sigmodon hispidus) with tail about half head-body length combined and less heavy (weight 2 3/4-7 oz/80-198 g), and fur coarse and grizzled, grayish above with mixed buff and black, and whitish below.
(3) House mouse (Mus musculus) with muzzle pointed, ears large, tail about as long as head plus body, small (about 1/2-1 oz/14-28 g), shorter (head, body and tail 5.25- 7.5″/6.5-10.2 cm), droppings 1/8-1/4″ (3-6 mm) long, rod-shaped with pointed ends.
(4) Most native rats and mice have hairy tails, hairs short or long, or if the tail is almost naked, it is also annulate (appears to be of ringlike segments).
Biology of the Sewer Rat (Norway/Brown/Wharf Rat)
Norway rats reach sexual maturity in 2-5 months. Pregnancy lasts an average of 23 days (range 21-25). The young/pups are blind and naked at birth. Hair appears in about 7 days and eyes open in 12-14 days. They are weaned at about 3-4 weeks and reach sexual maturity at 8-12 weeks. The average number of litters is 3-6 per year (range 3-12), each containing an average of 7-8 young (range 4-22), but averaging about 20 weaned/female/year. Adults live an average of 5-12 months in towns and cities, but much longer in captivity.
They have rather poor vision and are color blind, but their senses of hearing, smell, touch, and taste are keenly developed. Touch is via their vibrissae or long whiskers. They are good runners, climbers, jumpers, and swimmers (documented record is 1,300 ft or 400 m across open ocean).
A Norway rat requires 3/4-1 oz (21-28 g) of food and 1/2-1 oz (15-30 ml) of water each day, with the water coming from a nonfood source. This results in about 30-180 droppings and 1/2 oz/3 teaspoons (16 cc) of urine produced each day.
Historically, the disease most commonly thought of involving rats (roof rat primarily) is plague which is transmitted via fleas leaving an infected rat and attacking man. Fortunately, plague has not been found in rats in the United States for many years. Other transmittable diseases include murine typhus via fleas (also possibly via droppings and urine), infectious jaundice/leptospirosis/Weil’s Disease via urine in water or food, rat-bite fever via bites, cowpox virus (CPXV) via direct contact, trichinosis via undercooked pork, and food poisoning or Salmonellosis via droppings. Another problem is tropical rat mite dermatitis that is caused by these mites when they feed on humans.
Habits of the Sewer Rat (Norway/Brown/Wharf Rat)
Rats are primarily nocturnal in habit and they are cautious. Although they constantly explore their surroundings, they shy away from new objects and changes. Outdoors, Norway rats prefer to nest in burrows in the soil along railroad embankments, stream/river banks, piles of rubbish, under concrete slabs, etc. The burrow will have at least 1 entrance hole and at least 1 bolt-hole or emergency exit which is often hidden under grass, debris, etc. These are social animals and often many burrows will be located within a given area. An opening of greater than 1/2″ (12 mm) is required for entry into buildings. Indoors, Norway rats usually nest in basements and the lower portions of buildings in piles of debris or merchandise as long as it is not disturbed. Although Norway rats prefer the ground or lower levels of buildings and sewers, on occasion they may be found in attics, on roofs, and in other high places.
Norway rats are opportunistic feeders and although they will eat practically anything, they prefer meat, fish, and cereal. If the food material eaten proves to be disagreeable, they are quick to develop food/bait shyness. Once they find an acceptable/preferred food, rats tend to eat their fill in one or two visits and will return time after time; if the area of food is constantly disturbed, they may require several return visits to get their fill. They almost always require a nonfood or separate source of water. Norway rats will travel about 100-150 ft (30.5-45.7 m) from their harborage for food and/or water; in urban areas the average home range is about 25-100 ft (8-30.5 m). They will gnaw through almost anything to obtain food and/or water, even plastic or lead pipes.
Norway rats typically forage and feed at dusk and again prior to dawn, although they will forage several times each night and during the daytime. If the area is quiet and undisturbed, daytime activity may or may not indicate an overpopulation. They do carry off food to less disturbed areas for consumption, or to hoard.
Once established, Norway rats tend to follow the same route or pathway between their harborage and food and/or water sources. As often as possible, they follow vertical surfaces which their vibrissae or long whiskers can contact. Runways along vertical surfaces will usually include dark rub marks on the vertical surfaces where their oily fur makes contact. Their runway will be free of debris, and outdoors, the grass will be worn away to the bare soil.
Control of the Sewer Rat (Norway/Brown/Wharf Rat)
The key to any rat control program is pest identification, sanitation, harborage elimination, and rat-proofing the building. Control is based on the behavioral habits of the Norway rat. Some of the most important things to remember are:
- Rats defecate somewhat indiscriminately within their territories but mostly where they feed. Rat droppings serve as an indication of their presence and where control efforts should be concentrated. Nontoxic tracking powders can also be used to determine where they are most numerous.
- Rats will travel 100-150 ft (30.5-45.7 m) for food and/or water along established runways and usually with their vibrissae in contact with vertical surfaces. Look for rub marks and clean runways. Place traps or bait stations along runways and against vertical surfaces.
- Rats are gluttons. Place sufficient bait in each bait station for at least 1 meal (stop-feed baits), 2 meals (acute/single-feed baits), or more (chronic/multi-feed baits) Once a preferred bait is found, they utilize this bait until feeding stops. Secure the bait within the bait station because rats carry off and hoard food.
- Rats are cautious. Minimal disturbance is desirable. Prebaiting with unset snap traps is advisible, and secure to the trigger with unsected/unflavored dental floss. Prebaiting with nontoxic bait may be necessary in bait stations.
- Norway rats prefer meat, fish, and cereals. Use such high-protein baits and bait the center of glue boards and snap traps with such foodstuff, or use a large cockroach with its legs removed.
- Rats usually have a water source other than their food if their food has a low moisture content. Liquid baits are particularly effective when their normal water source can be reduced or eliminated.
- Glue boards harvest primarily juveniles while adults usually escape. Use glue boards in addition to other methods.
- Traps and bait stations are more effective if placed in corners (rats slow down for corners), and along established runways. Droppings will indicate the best placement sites.
- Outdoors, Norway rats usually live in ground burrows. Outdoors, gassing (fumigating) rat burrows is extremely effective. Follow label directions and do not gas burrows within 15 ft (4.6 m) of an occupied structure, or burrows which may run under or open into an occupied structure.
What do Sewer Rats (Norway/Brown/Wharf Rats) look like?
Introduction to the Roof Rat (Black/Ship Rat)
The roof rat is the smaller of the 2 commensal rats (Norway rat is larger) and the more common commensal rat in the subtropical and tropical regions of the world. It not only damages/destroys materials by gnawing, eats and contaminates stored food, but it is also of human health importance as a vector or carrier of disease organisms. Roof rats are usually thought to be of southeast Asian origin, and are now worldwide in distribution. In the United States, it is more common in the coastal states, seaports, and the southern third of the country.
Recognition of the Roof Rat (Black/Ship Rat)
Adult with combined head and body length 6-8″ (16-20 cm), tail length 7-10″ (19-25 cm; when pulled over body reaches or exceeds snout), usual weight 5-9 ozs (150-250 g) but up to 12 ozs (340 g). Fur soft, smooth, color usually brown with black intermixed, to gray to black above with underside white, gray, or black. With muzzle pointed, eyes large, ears large (can be pulled over eyes) and almost naked. Tail scaly, uniformly dark, longer than head and body combined. Adult droppings up to 1/2″ (12.5 mm) long, spindle-shaped with pointed ends.
Signs of Infestation of the Roof Rat (Black/Ship Rat)
- Gnaw marks. New gnawings or holes tend to be rough whereas, old gnawings are smooth from wear.
- Droppings. Fresh droppings are soft and moist whereas, old droppings are dried and hard; adult roof’s about 1/2″ (12-13 mm) with pointed ends vs Norway’s about 3/4″ (18-20 mm) with blunt ends.
- Tracks/footprints. Front foot 4-toed and print is in front of usually longer hind print with 5 toes. Fresh tracks are clear and sharp.
- Rub marks or dark, greasy markings on vertical surfaces. Fresh marks are soft, greasy, and easily smeared whereas, old marks are with the grease dry and flaky. Swing marks often present around rafters.
- Burrows. Not common, but if present they are shallow. They usually nest in or under dense vegetation.
- Runways. Travel routes may not be apparent outside because they may travel along fences or on overhead power or telephone lines. Indoors, they usually move along walls, stacked merchandise, etc. Active runways with greasy appearance, free of dust and cobwebs, with fresh tracks and/or droppings.
- Damaged goods. Roof rats prefer fruits, vegetables, and cereal whereas, Norway rats prefer meat, fish, and cereal.
Similar Groups to the Roof Rat (Black/Ship Rat)
(1) Norway rat (Rattus norvegicus) with blunt muzzle, small eyes, ears small and hairy, tail bicolored and shorter than head plus body, droppings rod-shaped with blunt ends.
(2) Hispid cotton rat (Sigmodon hispidus) with tail about half head-body length combined and less heavy (weight 2 3/4-7 oz/80-198 g), and fur coarse and grizzled, grayish above with mixed buff, black, and whitish below.
(3) House mouse (Mus musculus) with tail about as long as head plus body, smaller (about 1/2-1 oz/14-28 g), shorter (head, body, and tail 5.25-7.5″/6.5-10.2 cm), droppings 1/8-1/4″ (3-6 mm) long, rod-shaped, with pointed ends.
(4) Most native rats and mice with tail hairy, hairs short or long, or if tail almost naked, it is also annulate (appears to be of ringlike segments).
Biology of the Roof Rat (Black/Ship Rat)
Roof rats reach sexual maturity in 2-5 months. Pregnancy lasts an average of 22 days. The young/pups are blind and naked at birth, with hair appearing in about 7 days and eyes opening in 12-14 days. They are weaned at about 3-4 weeks. The average number of litters is 4-6 per year, each containing an average of 6-8 young. Adults on an average live 9-12 months.
They have rather poor vision and are color blind, but their senses of hearing, smell, touch, and taste are keenly developed. Touch is via their vibrissae or long whiskers. They are good runners, excellent climbers and jumpers, and if forced, rather good swimmers.
A roof rat requires 1/2-1 oz (14-28 g) of food and 1-2 oz (30-60 ml) of water each day, with the water often coming in part or totally from its food. This results in about 30-180 droppings and 1/2 oz/3 teaspoons (16 cc) of urine per day.
Historically, bubonic plague has been associated with the roof rat and its fleas, which move from infested rats to man. Fortunately, plague has not been found in rats in the United States for many years. However, plague is found in wild rodents in several south- western states and transmission to humans via infected fleas does occasionally occur. From 1990-2005, CDC recorded a total of 107 cases of plague in the United States, with 81 (76%) being bubonic and 11 (10%) of the total being fatal. In 2006, there were 13 human cases (New Mexico 7; Colorado 3; California 2; and Texas 1). Carriers were primarily rabbits, but also dogs, a wood rat (Neotoma micropus Baird), and a rock squirrel (Spermophilus variegatus Erxleben).
Other transmitted disease organisms include murine typhus via fleas (also probably via droppings and urine), infectious jaundice/leptospirosis/Weil’s Disease via urine in water or food, rat-bite fever via bites, trichinosis via undercooked pork, and food poisoning or Salmonellosis via droppings. Another problem is tropical rat mite dermatitis that is caused by these mites when they feed on humans.
Habits of the Roof Rat (Black/Ship Rat)
Roof rats are primarily nocturnal in habit and colonies contain some members that are very cautious. Although they constantly explore their surroundings, they shy away from new objects and changes. Roof rats prefer to nest in the upper parts of structures, but may be found under buildings as well as occasionally in basements and sewers. Outdoors, they prefer to nest in higher places such as in trees but may occasionally be found in burrows in or under vegetation around the structure. These are social animals but less so than Norway rats. Several nests may be located within a given area. An opening of greater than 1/2″ (12 mm) is required for entry into buildings.
Although they will eat practically anything, roof rats prefer naturally-occuring seeds, nuts, fruits, and berries when in season. If available, they feed on slugs and snails, which may become a large part of their diet. They also feed on insects including American, brown, and smokybrown cockroaches. If they live near waterways, roof rats will feed on fish, shellfish, and other aquatic organisms. Around human structures and livestock operations, they will go after any easily available food. If the eaten food material proves dis- agreeable, they are quick to develop food/bait shyness. Once they find an acceptable/preferred food, rats tend to return time after time.
Roof rats typically feed at dusk and again prior to dawn, although they will forage several times each night and during the daytime. They forage in family groups of up to 10 rats. Roof rats prefer to feed in situations that give them protective cover. They do cashe all kinds of food and seeds in natural cavities or structural voids. Roof rats tend to eat smaller amounts of food in several places, a behavior somewhat between that of a house mouse and Norway rat.
Roof rats do not distribute themselves evenly throughout the grounds/property and/or structure, but prefer to locate in clusters in arial areas or in the upper regions of structures. Once established indoors, roof rats tend to follow the same route or pathway between their harborage and food and/or water sources. Runways along vertical surfaces will usually include dark rub or swing marks on the vertical surface where their fur makes contact. Their runways will be free of debris, and outdoors, the grass will be worn away to the bare soil.
Control of the Roof Rat (Black/Ship Rat)
The key to any rat control program is pest identification, sanitation, harborage elimination, and rat-proofing the building. Control is based on the behavioral habits of the roof rat. Some of the more important things to remember are:
- Rats defecate where they spend most of their time. Use rat droppings as an indication of where to concentrate the control efforts. Nontoxic tracking powder can also be used to determine where they are most numerous.
- Roof rats commonly travel up to 300 ft ( 91.5 m) for food and/or water along established runways. Look for rub/swing marks and clean runways. Place traps or bait stations along runways and against vertical surfaces. Glue boards wired to traveled pipes, rafters, etc. are effective.
- Roof rats feed several places, but they feed in groups of up to 10 rats. Place sufficient bait in each bait station for at least 1 meal (stop-feed baits), 2 meals (acute/single-feed baits), or more (chronic/multi-feed baits), but make more placements than for Norway rats.
- Some colony members are cautious. Minimal disturbance is desirable when putting out traps and/or bait stations. Prebaiting with unset snap traps or prebaiting with nontoxic bait in bait stations may be necessary. Tie the bait down on the trigger of snap traps with unsented/flavored dental floss.
- Roof rats prefer fruits, vegetables, and cereals. Use such high-carbohydrate baits. Bait the center of glue boards and snap traps with such foodstuffs or with a large cockroach with its legs removed.
- Rats usually have a water source other than their food if their food has a low moisture content. Liquid baits are particularly effective when their normal water source can be reduced or eliminated.
- Glue boards harvest primarily juneniles and adults usually escape. Use glue boards in addition to other methods.
- Traps and bait stations are more effective if placed in corners (rats slow down for corners), and along established runways. Droppings will indicate the best placement sites.
- Roof rats sometimes nest in ground burrows. Outdoors, gassing (fumigating) rat burrows is extremely effective. Follow label directions and do not gas burrows within 15 ft (4.6 m) of an occupied structure, or burrows that may run under or open into an occupied structure.
What do Roof Rats (Black/Ship Rats) look like?
Introduction to Woodrats/Packrats/Traderats
The common name of woodrat originates from the fact that they typically make their nests utilizing wooden sticks. They are also referred to as packrats because they cache various man-made objects in their nests, and that of trade rats because when returning to their nest with nesting materials if they encounter something more desirable (especially anything shiny), they will exchange for the more desirable material and return with it. Nationwide, woodrats are of minor nuisance pests. However, they are becoming increasingly more important as a pest group as urban sprawl continues, especially in the southwestern United States (e.g., Arizona, Utah, and New Mexico). When woodrats move into buildings, they can cause serious gnawing damage to the structure, wiring, and other utility elements. In addition, woodrats are of medical concern because they serve as reservoirs for disease organisms that cause Chagas’ disease, Lyme disease, etc.
Woodrats occur throughout North America and range in habitats from low, hot, dry deserts to cold, rocky slopes above the timberline. Of the approximately 22 species known to occur in North America, only the 8 listed below are encountered by property owners. Only the first 4 species (treated in detail below in the Representative Species and Habits sections) of the 8 species listed below are of any high pest significance. The 8 pest species are:
- Western white-throated woodrat, Neotoma albigula Hartley.
- Southern plains woodrat, Neotoma micropus Baird.
- Mexican woodrat, Neotoma mexicana Baird.
- Dusky-footed woodrat, Neotoma fuscipes Baird.
- Eastern woodrat, Neotoma floridana Ord; also called the Florida woodrat. (Widespread: range extends from latitude of southeastern New York through the Central United States, south to the Gulf of Mexico, over about 20 states.)
- Desert woodrat, Neotoma lepida Thomas. (California, Nevada, Utah, and Arizona.)
- Bushytailed woodrat, Neotoma cinera Ord. (Northwest quadrant, occurring in 11 states and into west/southwestern Canada.)
- Stephens woodrat, Neotoma stephensi Goldman. (Northern Arizona and New Mexico, southern Utah.)
Currently (2016) only the first 3 woodrat species (numbers 1-3 above) are listed on EPA registered rodenticide labels. Number 4, the dusty-footed woodrat of California (Western California) is probably the most pestiferous. The last 4 woodrat species listed above (numbers 5-8), typically occur away from human structures and play important ecological roles, but are not structural pests. However, in areas where these 4 woodrats occur, they can be occasional invaders in unoccupied structures such as country homes, summer cabins, detached garages, storage sheds, stored campers and the like where they do gnawing damage, create messes, and possibly deposit pathogens. To a pest professional’s customers, all furry rats are the same and they will want them gone.
Recognition of Woodrats/Packrats/Traderats
In general, woodrats are about like Norway rats in size and tend to look like overgrown deer mice. Adult head and body length about 7-8″ (178-204 mm), tail about 6 1/2-7 1/2″ (165-190 mm) long. Color varies with species, from gray to brown to blackish; bellies and feet range from bright white to light brown. Ears are large, eyes are large, bulging, and black; fur is very long, fine, and soft; tails are hairy, and facial whiskers are very prominent.
Similar Groups to Woodrats/Packrats/Traderats
(1) Norway rat (Ratus norvegicus (Berkenhout) with tail almost naked, scaly (vs hairy), fur coarse, shaggy, and brown with scattered black hairs (not soft and fine); (2) Roof rat (Ratus ratus Linnaeus) with tail almost naked, scaly (vs hairy), fur brown with scattered black hair; (3) Cotton (Oryzomys sp.) and rice rats (Sigmodon sp.) with tail almost naked but annulate (containing rings); (4) White-footed mice (Peromyscus sp.) smaller, about 5-9″ (12.8-22 cm) long (vs 12-16″ or 35-45.2 cm) from tip of nose to tip of tail, tail bones longer than half body length; (5) Other common rodents with long-haired tails.
Representative Species of Woodrats/Packrats/Traderats
(1) Western white-throated woodrat. Adult head and body length about 5 3/4-8 1/4″ (144-210 mm), tail about 4 1/4-6 3/4″ (120-193 mm) long, weight about 4 1/2-10 oz (127-280 g). Color of body gray with upper back darker, belly white or grayish, hairs of throat white to their bases, feet white, tail bicolored, brownish gray above and whitish below. Occurs from extreme southwestern Colorado and southeastern Utah, west through extreme southern Nevada to southeastern California, and southward through most of Arizona and western New Mexico, and then into northwestern Mexico.
(2) Southern plains woodrat. Adult head and body length about 7-9 1/2″ (180-245 mm), tail short and heavy, about 5-7″ (130-175 mm) long, weight about 7-11 1/4 oz (180-317 g). Color of body steel-gray above, belly pale gray, hairs on throat, breast, and feet white to bases, tail dark grayish above and white below. Range extends south-ward from southwestern Kansas, through western Oklahoma, western Texas, and most of New Mexico, and southward through northeastern Mexico.
(3) Mexican woodrat. Adult head and body length about 5 3/4-8″ (147-204 mm), tail about 4 3/4-6 1/4″ (123-157 mm) long, weight about 4-6 3/4 oz (112-194 g). Color of body grayish to brownish or rusty with darker gray mixed in (approaching black in some lava areas), belly whitish or yellowish, feet white, tail bicolored, blackish above and whitish below. Occurs primarily in the montane regions from northern Colorado and the 4-corners area southward to Honduras.
(4) Dusky-footed woodrat. Adult head and body length about 7-9 1/2″ (180-240 mm), tail about 5-9 1/2″ (148-240 mm) long, weight about 8-15 1/4 oz (200-430 g). Color of body buff-brown above, belly grayish to whitish, tail brown above, slightly paler under-neath, and feet and ankles dusky with toes and claws white. Occurs in western Oregon, southward through northern California and then southward down the western California coastal area to the Santa Barbara area.
Biology of Woodrats/Packrats/Traderats
Unlike the commensal rodents, populations of woodrats do not increase quickly. In the north, they have 1 litter each year. The breeding season is from February to March with birthing occurring during March to May. The gestation period is 33-43 days. In the south, they have 2-5 litters each year, with the breeding and birthing occurring year-round. They usually have 2-4 young per litter (range 1-7 young/litter), and the young are weaned when about 4-7 weeks old. Adult life span is up to 3 years, average about 6-12 months due to predation. They tend to be solitary animals except during mating and rearing times.
Woodrats are of medical importance because they have been found to be reservoirs of a wide range of pathogenic viruses, bacteria, and protozoans that may present disease risks to humans. Below is a listing of important diseases associated with the four pest species. If further information is needed, consult (www.cdc.gov) for the profiles of rodent-borne diseases associated with woodrats.
Western white-throated woodrat:
- Borrelia burgdorferi (Lyme disease) in Colorado;
- Arenaviruses (e.g., hemorrhagic fevers, Lymphocytic choriomeningitis (LCMV) others) primarily in the southwestern United States.
Southern plains woodrat:
- Typanosoma cruzi (Chagas’ disease; 6+ species identified as reservoirs; parasitic blood-infesting protozoans).
- Arenaviruses (See above).
Mexican woodrat:
- Arenaviruses (See above).
- Borrelia burgdorferi (Lyme disease) in Colorado.
Dusky-footed woodrat:
- Anaplasma (formerly Ehrlichia) phagocytophilum (human granulocytic anaplasmosis/HGA; formerly HGE).
- Borrelia burgdorferi (Lyme disease) in California and Oregon.
Habits of Woodrats/Packrats/Traderats
Woodrats are nocturnal in habit. Their nests are typically built out of sticks and are called “houses.” The different species occupy specific habitats or ecological areas. The range of woodrats is about 0.5-1.5+ acres (2,024-6,070 sq m), or about 200 feet (61 m) along well-marked trails from nest to feeding area. They drink very little water, but during the dry season they may make use of water-laden plants such as the fleshy stems of cacti in desert areas.
The foods of woodrats include plant tissues (e.g., roots, stems, and leaves), seeds, nuts, acorns, and fruits. For protein, they eat insects, snails, birds, small mammals, and carrion. They also eat easily accessible human and/or pet food.
As is typical of rodents, woodrats constantly gnaw (the genus name Neotoma means “new teeth”). Woodrats gnaw on electrical lines in wall voids and attics posing serious dangers to human safety from the resultant shorts and fires. In vacant summer cabins, they can cause serious damage to the furniture and stored items. Given their habit of caching, various combustible materials can accumulate in wall, ceiling, and floor voids creating fire hazards. Around landscaped yards and in orchards, woodrats damage vegetation by clipping young limbs (1/4″ or 6 mm in diameter) of fruit trees, or rarely girdling small trees and shrubs.
The habits of woodrats vary according to the species. Some occupy deserts to densely wooded and cavernous areas, while others are ground dwellers or live in trees. Specifically:
- Western white-throated woodrats. Occur in brush lands and in rocky cliffs with shallow caves. Most common in the Sonoran and Chihuahuan desert grassland and desert shrub habitats, and will utilize riparian areas when available. Houses usually constructed among cacti, brush, or in cliff caves and measure 3-10 ft (1-3m) in diameter and up to 3 ft (1 m) high, usually. White-footed woodrats feed on cactus, mesquite beans, and seeds, fruits, flowers, and occasionally on beetles, ants, and small reptiles; some may store food in their houses.
- Southern plains woodrats. Occur in semi-arid brush lands and areas of thorny vegetation located in low valleys and plains. Constructs houses of brush, cactus, and debris 3-5 ft (0.9-1.5 m) in diameter and almost as tall, typically positioned among thorny vegetation such as mesquite and cactus. It feeds on seeds, acorns, and cacti; stores food.
- Mexican woodrats. Occur among rocks and cliffs, often in mountainous areas containing conifer trees. This woodrat rarely constructs houses. Sticks and debris are simply dropped into crevices among rocks and cliffs, or under logs or tree roots, and in deserted buildings. Mexican woodrats feeds on nuts, acorns, seeds, fruits, mushrooms and cacti, but mainly on foliage. Occasionally stores its food.
- Dusky-footed woodrats. Occur in the heavy chaparral, streamside thickets of deciduous or mixed hardwoods. It constructs 1-3 large houses of sticks on the ground or up in trees. Establishes colonies of 3-15 or more multiple homes within their habitats. Dusky-footed woodrats feed on nuts, acorns, seeds, fruits, vegetation, and fungi; stores food in its houses. The dusky-footed woodrat can be a pest in homes and summer cabins located in forested/mountainous areas. It is an excellent climber and often gains access via rooftops or attics by climbing, or from overhanging tree branches. They may locate their nests in the attic or in wall voids. Nests are commonly located in attics, overhanging soffits, and wall void spaces.
Control of Woodrats/Packrats/Traderats
The presence of woodrats may be indicated by damage to the interior contents of cabins or homes located in conducive areas. Finding large stick nests in a shed, beneath a porch or deck, in a crawl space, or in an attic would indicate their presence.
Several methods of control are available. Select the one or combination that best suits the situation at hand:
- Exclusion. This is the most permanent way to keep woodrats out of a structure. It is done in the same manner that would be used to exclude Norway and roof rats. Because access is usually at the roof or attic level, pay particular attention to the removal of all over-hanging tree limbs and cut back all tree limbs 6 ft (2 m) from the roof. Also, look for openings around roof dormers, gables, skylights, and attic vents, eaves, broken roof shingles or tiles, etc. Before closing such openings, be sure that the woodrats have not been unknowingly trapped inside the structure.
- Live-trapping. Live-catch wire cage traps 16x5x5″ (40.6×12.7×12.7 cm) are elective for woodrats. Soft nesting materials and/or small shiny objects (e.g., ball of aluminum foil are good attractants.
- Lethal trapping. The traditional rat-size snap traps work well on woodrats. Bait with a prune, raisin, or shelled nut tied on to the trigger with non-flavored/scented dental floss. Place the traps across the rat’s runways. Woodrats are not fearful of new objects found in their environment and tend to investigate these traps.
- Toxic baits. Anticoagulant rodenticide baits are registered for ONLY 3 woodrat species (see above). Only block bait formulations are recommended for woodrats because the blocks facilitate the bait being consumed where it is encountered and it is thus less likely to be cached in areas that can harm non-targets. Baits are most effective when carefully placed near the woodrat’s major runways, feeding sites, or nests (i.e., inspection is important). Always secure bait blocks with wire or via nailing the bait to a structural element. Bait stations are NOT recommended for woodrats because woodrats fill and jamb the stations with sticks and other debris.
Important
: Before using rodenticides for woodrats, ALWAYS CONFIRM that the pest woodrat is on the rodenticide label and is not a threatened or endangered species. Otherwise, use exclusion and live trapping techniques given above.
What do Woodrats/Packrats/Traderats look like?
Introduction to the Pigeon/Rock Dove
Pigeons were bred from the European rock dove and introduced as a domestic bird into North America circa 1606. They are now found feral/wild in virtually every city and in most rural areas. Pigeons are of medical concern because more than 50 diseases and ectoparasites have been associated with pigeons, their nests, and droppings. Probably the best known is the lung disease histoplasmosis. They are worldwide in distribution except for the cold northern and southern areas.
Recognition of the Pigeon/Rock Dove
Adults average about 13″ (33 cm) long; average weight about 13 oz (368 g). Stocky/robust, with a short rounded fanlike tail. Color varies from white to black but usually bluish gray with black bands, 2 narrow cross bands on each wing and a broad terminal tail band, white rump, and reddish feet, head dark and often with greenish-purplish iridescence on neck. Each of 2 legs short, bearing 1 rear-projecting and 3 forward-projecting toes. Body and wings covered with feathers and horny bill short, lacking teeth. Voice soft, with guttural series of rolling coos.
Similar Groups to the Pigeon/Rock Dove
(1) Mourning dove (Zenaida (=Zenaidura) macroura) smaller, buff colored, and with long central tail feathers giving pointed appearance to tail.
(2) Ringed turtle-dove (Streptopelia risoria) pale tan overall with narrow black collar around back of neck.
(3) White-winged dove (Zenaida asiatica) lacks black bands and with large white wing patches conspicuous when in flight.
Biology of the Pigeon/Rock Dove
Pigeons are monogamous, pairing for life. About 8-12 days after mating, typically 2 (range 1-2) white eggs are laid per clutch in the nest. Eggs require about 17- 19 days incubation. Hatchlings (squabs) are almost featherless and are totally dependent on the parent birds for warmth and food. For the first 5 days, hatchlings are fed predigested food called “pigeon milk” that is produced in the parent’s crop. For the next 5 days, water and grain are added to their milk, and finally they are fed only grain and water. Young pigeons usually make their first flight when about 35-37 days old, but may leave the nest when 4-6 weeks old. Several broods are reared each year with more eggs being laid before the proceeding brood is weaned. Breeding is year round but peaks in the spring and summer. Wild pigeons often live for 15 years and captive pigeons for 30 years or more. In the urban setting, pigeons usually live for 3-4 years.
Pigeons have color vision, a hearing range very close to that of humans, and have poorly developed senses of taste and smell. Although they cannot think, pigeons are capable of conditioned learning.
Pigeons, their nests, and droppings are of medical concern because of the over 50 diseases and ectoparasites associated with them. Diseases include encephalitis (St. Louis, eastern and western equine), histoplasmosis, Newcastle disease, chlamydiosis, and salmonellosis which can affect human and animal health, and severe cases may result in death. The ectoparasites include mites and ticks that often bite humans or infest domestic animals, causing extreme discomfort. Other arthropods, such as dermestid beetles, clothes moths, flies, and stored product pests, associated with the nests and droppings may invade structures.
Habits of the Pigeon/Rock Dove
Along with damage and nuisance problems, there are 4 behavioral habits requiring consideration. These are feeding, nesting, roosting, and loafing.
Pigeons prefer to feed on seeds, grain, some fruit, and green feed. However, they will readily feed on garbage, animal matter such as insects and spiders, livestock manure, and many other foods when their preferred food is scarce. Pigeons prefer flat or smooth surfaces, such as roof tops, for feeding. They also consume enough grit to ensure proper digestion. An adult consumes about 1 lb/453 g of food per week. Feeding may occur near the nesting or roosting site(s), but often it is done some distance away.
Nests are loosely constructed and usually consist of sticks, stems, leaves, and other debris. They are built on ledges of structures or cliffs, or in caves. The abundance of clifflike nesting sites, especially on older buildings, is one of the primary factors that attract pigeons to cities. Often nesting and roosting occur in the same general area, but they can be distant.
Roosting sites are where pigeons rest or sleep. They usually involve some kind of perch that is often high off the ground, such as exposed roof girders, protected ledges, etc. Roosting sites may or may not be near nesting, feeding, or loafing areas.
Loafing is loosely defined as when pigeons are not feeding, nesting, or roosting. Loafing may occur almost anywhere pigeons are not constantly disturbed.
Pigeons have very acidic droppings which can deface marble, limestone, painted surfaces, statues, car finishes, etc. Fresh droppings can cause objectionable odors and slippery situations on sidewalks, roads, fire escapes, and other flat surfaces. Droppings, feathers, and nesting materials can contaminate unprocessed grain and packaged foods. Pigeons also have diseases, ectoparasites, and other pests associated with them as mentioned above. Although of minor importance, pigeons can be a problem around airports, especially if there is a garbage dump, railroad siding, or grain field nearby.
Control of the Pigeon/Rock Dove
Pigeon control or management begins with the most important step, the survey. The survey should address the following: location of problem, species observed (pigeons/nontargets and numbers), habitat (food, water, nesting sites), special equipment, time constraints, analysis of problem, public relations issues, recommended control procedures, and pricing considerations. The site should be visited on several days when typical/normal site activity and weather is occurring. On each day selected, 3 visits should be made (sunrise, midday, and late afternoon), and observations should be recorded with date and time. Minimal equipment includes binoculars, bird field identification guide, watch, site plan or map, and reference manual giving biology, habits, and control.
Once the species involved (pigeons and nontargets) are determined via the survey, appropriate federal, state, and local regulations should be checked. Pigeons are not protected by the federal endangered species act or migratory bird statutes, but they are protected by some states; if the area is a bird sanctuary, then local permits are also required.
Many options are available for bird control. There are 5 methods that do not utilize toxicants. The first is exclusion which involves structural modification (e.g. change ledge angle to 45°), the installation of plastic netting, and/or the use of repellents such as plastic and metal spines, monofilament and steel lines, and gels and pastes. The second is sanitation which involves the reduction or elimination of feeding sites and temporary water sources. The third involves the use of sound devices such as noise-making devices (usually not suitable for urban areas). The fourth is trapping which can be effective if the birds are destroyed and not released; otherwise, they will return home or create problems elsewhere. Finally, shooting can also be effective for removing birds within some kinds of buildings.
There is 1 method of control utilizing chemicals or toxicants. This can be considered a chemical frightening agent and involves grain coated with a material that elicits distress symptoms and calls when consumed and results in the remaining portion of the flock being repelled. Its use involves a prebaiting program, and the entire cycle may have to be repeated if other pigeons move in; it may be lethal to glutton pigeons. If nontarget birds are attracted to this treated grain, then the program must be stopped immediately.
What do Pigeon/Rock Dove look like?
Introduction of the House/English Sparrow
House sparrows were introduced from England into Central Park, New York City, in 1850; hence the name English. They rapidly spread throughout the continent. This is not a true sparrow (Fringillidae) but a member of the weaver finches. House sparrows are nuisance pests because they displace desirable songbirds, and their droppings deface buildings, statues, etc. They are of medical concern because there are over 29 diseases and ectoparasites associated with them, their nests, and droppings. House sparrows are found in the southern half of Canada, throughout the United States, and down through Central and South America.
Recognition of the House/English Sparrow
Adults about 5 3/4-6 1/4″ (14.6-15.9 cm) long; average weight about 1 oz (28.3 g). Stocky. Color sexually different, males with wings and back brownish streaked with black, wing with white bar, bill black, top of head (crown) gray, chestnut stripe behind eye, large black patch (bib) under beak on throat and upper breast and underparts gray, but in winter black and chestnut marks hidden by gray feather tips and, bill yellowish; females dusky/dirty brownish gray above with faint blackish stripes on wings and back and faint chestnut stripe behind eye, beak yellowish (lack black bib below beak), and gray below. Voice shrill, monotones, noisy chirping, with no true song.
Immature sparrows similar to females in coloration.
Similar Groups to the House/English Sparrow
(1) Eurasian tree sparrow (Passer montanus) with head chocolate brown and cheeks white with dark patch over ears (below eye); occurs in St. Louis, Missouri area and western Illinois.
(2) Song sparrow (Melospiza melodia) lacks gray cap on head and black bib under beak.
(3) Chipping sparrow (Spizella passerina) with rust-colored head cap and lacks black bib under beak.
(4) Lark sparrow (Chondestes grammacus) with chestnut brown and white striped head and lacks black bib under beak.
Biology of the House/English Sparrow
Females begin egg laying in March and April in the northern United States. They usually lay 5-6 eggs (range 3-9) per clutch. The eggs are usually pale greenish white (vary from white to light blue) and are always speckled. The eggs hatch after 10-17 days incubation. The young first fly at about 14 days and leave the nest shortly thereafter. There are at least 2 and up to 5 broods each year, but there is an annual natural mortality rate of 40-60% among mature birds which keeps the reproductive potential in check.
House sparrows, their nests, and droppings are of medical concern because of the over 29 diseases and ectoparasites associated with them. Diseases include encephalitis (St. Louis, eastern and western equine), histoplasmosis, Newcastle disease, chlamydiosis, and salmonellosis which can affect human and animal health, and severe cases may result in death. House sparrows are considered one of the major reservoirs of St. Louis encephalitis. The ectoparasites include primarily mite species that can bite humans or infest domestic animals, causing extreme discomfort. Other arthropods, such as dermestid beetles, clothes moths, and stored product pests, associated with the nest and droppings may invade structures.
Habits of the House/English Sparrow
House sparrows prefer to nest in protected areas in, on, or near buildings. Such places include building ledges, gutters, signs, light fixtures, under eaves and bridges, electric power pole cross supports and transformers, and inside warehouses, airport hangers, and stadium roofs. They also will displace other birds, such as robins, wrens, and purple martins, from their nests, destroy the eggs, and use the nest to rear their own. When they do construct nests, they are rather large and flimsy and made of grass, straw, feathers, and other debris. Nests are constructed by both sexes. Sparrows frequently use the same nesting sites over and over.
House sparrows tend to be very territorial, both as individuals and as flocks. They restrict their nesting and feeding sites to specific locations. Sparrows tend to congregate in urban areas during the winter and disperse to rural areas in the spring.
They feed mostly on grains and seeds but also on tree and plant buds, sprouting plants, flowers, and small, soft fruits (cherries, grapes, etc.). In rural areas they cause considerable damage to crops, such as wheat and sorghum. Individuals eat up to 0.2 oz (6 g) per day. Many sparrows feed at cattle feed lots, dairies, and hog and poultry farms where food is abundant. During the breeding season, they feed mostly insects to their nestlings.
They contaminate animal feed during their feeding activities, and their droppings cause defacement of buildings, statues, etc. Their droppings also damage styrofoam insulation found in warehouses, and in hog and poultry-raising facilities. Their nests have caused short-circuits and fires in electrical substations. When they enter malls, department stores, warehouse and food processing plants, they are nuisances and contaminate much with their droppings.
Control of the House/English Sparrow
House sparrow control or management begins with the most important step, the survey. The survey should address the following: location of problem, species observed (house sparrows/nontargets and numbers), habitat (food, water, nesting sites), special equipment, time constraints, analysis of problem, public relations issues, recommended control procedures, and pricing considerations. The site should be visited on several days when typical/normal site activity and weather is occurring. On each day selected, 3 visits should be made (sunrise, midday, and late afternoon), and observations should be recorded with date and time. Minimal equipment includes binoculars, bird field identification guide, watch, site plan or map, and reference manual giving biology, habits, and control.
Once the species involved (house sparrows and nontargets) are determined via the survey, appropriate federal, state, and local regulations should be checked. House sparrows are not protected by the federal endangered species act or migratory bird statutes, but they may be protected by some states; if the area is a bird sanctuary, then local permits are also required.
Many options are available for bird control. There are 3 methods that do not utilize toxicants. The first is exclusion which involves structural modification (e.g. change ledge angle to 45°), the installation of plastic netting on portions of buildings (denies access to perching and/or roosting sites), and/or the use of repellents such as plastic and metal spines, monofilament and steel lines, and gels and pastes. Second is sanitation which involves the reduction or elimination of feeding sites and temporary water sources. The third involves the use of sound devices such as noise-making devices and distress calls (usually not suitable for urban areas).
There is 1 method of control utilizing chemicals or toxicants. This can be considered a chemical frightening agent and involves grain coated with a material that elicits distress symptoms and calls when consumed and results in the remaining portion of the flock being repelled. Its use involves a prebaiting program, and the entire cycle may have to be repeated if other sparrows move in; it may be lethal to glutton sparrows. If nontarget birds are attracted to this treated grain, then the program must be stopped immediately.
What does the House/English Sparrow look like?
Introduction to Woodpeckers
Their common name reflects that they routinely peck wood, for food (insects), for shelter (nests), and for drumming to establish territories and attract mates. Woodpeckers may be nuisance or damaging pests when they attack wood structures, but they are federally protected. Although this family includes the sapsuckers (horizontally band a tree trunk with small 1/2″/6 mm holes) and the flickers, this section is restricted to woodpeckers. There are 22 species found in Canada, the United States, and Mexico.
Recognition of Woodpeckers
Depending on the species, adults about 6-18″ (15.2-45.7 cm) long. Color varies greatly between species but most males with some red on head and many species with black and white marks. Bills stout, sharply pointed, chisellike. Tail feathers stiff and spiny, used as support prop. Legs short, each with 2 sharp-clawed backward-pointed toes.
Similar Groups to Woodpeckers
(1) Sapsuckers (Picidae) almost always with long white wing patch, if lacking then with yellow belly and barred back.
(2) Flickers (Picidae) with black patch across its chest and usually brown barred back.
Representative Species of Woodpeckers
The 4 species listed below are those that typically cause problems on structures, from drumming to actual damage.
- Downy woodpecker, Picoides pubescens (Linnaeus). Adults about 6″ (15.2 cm) long; color black and white, head with black and white stripes, back black with white in center, wings black with white spots, outer tail feathers white with narrow black bars, underparts white, male with small red patch on nape (back of neck); bill short, about half head length; found in southeastern Alaska east to Newfoundland and south to southern California and Florida, with northern birds migrating south in winter.
- Hairy woodpecker, Picoides villosus (Linnaeus). Adults about 9-9 1/4″ (22.9-23.5 cm) long; color black and white, similar to downy woodpecker except outer tail feathers white, lacking black bars; bill almost as long as head; found in southern Alaska east to Newfoundland and south to Florida and Central America, with some northern birds migrating south in winter.
- Pileated woodpecker, Dryocopus pileatus (Linnaeus). Adults about 16 1/2-18″ (41.9-45.7 cm) long; color mostly black with white face and neck stripes, white wing linings, and male with bright red crest, crown, forehead, and mustache (off beak base) but female with red crest and crown only; found in southern Canada south to northern California in west and in eastern United States through Florida.
- Red-bellied woodpecker, Melanerpes carolinus (Linnaeus). Adults about 9-10″ (22.9-25.4 cm) long; color with head and belly tan, back, tail, and wings black barred with white, and male with red crown and nape (back of neck) but female with red nape only; found in the eastern United States.
Biology of Woodpeckers
This can be summarized for the 4 representative species as follows:
- Downy woodpecker. Females lay 4-5 white eggs. The incubation period is 12 days. The young hatch helpless and are dependent on parental care. Young birds leave the nest in about 12 days. There are 1-2 broods per year. They feed on a variety of insects including wood-boring beetles; also found at feeders for suet and sunflower seeds.
- Hairy woodpecker. Females lay 4-6 white eggs. The incubation period is 11-12 days. The young hatch helpless and are dependent on parental care. Young woodpeckers leave the nest in 28-30 days. There is 1 brood per year. They feed on a variety of insects including wood-boring beetles; also found at feeders for suet and sunflower seeds.
- Pileated woodpecker. Females lay 3-5 white eggs. The incubation period is 15-16 days. The young hatch helpless and are dependent on parental care. Young birds leave the nest in about 28+ days. There is 1 brood per year. They feed on carpenter ants (especially in winter), beetles, and other insects; they also feed on seeds and come to feeders for suet mixes.
- Red-bellied woodpecker. Females lay 3-8 white eggs. The incubation period is 12-14 days. The young hatch helpless and are dependent on parental care. Young woodpeckers leave the nest in 25-30 days. There are 2-3 broods per year. They feed on wood-boring beetles, grasshoppers, ants, other insects; they also eat fruit, berries, acorns, beechnuts, seeds, and come to feeders with suet.
Habits of Woodpeckers
For the 4 representative species, this can be summarized as follows:
- Downy woodpecker. They excavate a nest cavity in dead wood and rarely accept a nest box. Males drum to announce their territory and to attract a mate during breeding season. They are typically found in woods, wood lots, parks, gardens, farms, suburbs, and frequent suet feeders in winter.
- Hairy woodpecker. Similar to downy woodpecker except they prefer deciduous/hardwood forests in addition to the other habitats given.
- Pileated woodpecker. They excavate a nest cavity in dead wood about 15-70 ft (5-21m) off the ground. The entrance hole is about 3 1/2″ (8.9 cm) in diameter and the cavity may be 10-24″ (24.5-61 cm) deep. Feeding holes are squarish and about 3-6″ (7.6-15.2 cm) in size; occasionally they may excavate a long gash when after ants. Unmated males drum to attract a mate, or drumming can be done between mated pairs as part of the courtship. They are typically found in mature forests and along their borders as well as in the suburbs. Their territory size may be 150-200 acres (60.7-80.9 ha).
- Red-bellied woodpecker. They excavate a nest cavity in a living tree or one which recently died, but they will also use an abandoned hole in an old stump, fence post, or utility pole, as well as a bird house. Males and females mutually drum in 1-second bursts as a part of courtship, usually with one inside a potential nest hole and the other on the outside. They habitually store food by wedging it deeply in crevices. They are found in woodlands, parks, and the suburbs.
Woodpeckers occasionally achieve pest status because of their drumming on struc- tures and/or attacking wood structures because of an insect infestation, for nut storage, or as a potential nesting site. For drumming purposes, they prefer substrates that resonate loudly, such as gutters, vents, metal siding, drain pipes, chimney caps, roof vents, etc. Drumming may be done several times each day and can continue for several days or weeks. It may result in damage to the surface used and/or a most annoying racket.
Woodpeckers will attack the wood of a structure especially if it is insect infested. The acorn woodpecker (Melanerpes formicivorus Swainson), which occurs in the western and southwestern states, drills a series of closely spaced holes just large enough to store 1 acorn in each. Sometimes wood is pecked and explored as a possible nesting site, with cedar and redwood siding being preferred.
Control of Woodpeckers
Woodpeckers are protected by the Federal Migratory Bird Treaty Act as migratory, nongame birds. Some species are also protected by state laws. Two species are on the Endangered Species list, namely the red-cockaded woodpecker (Picoides borealis Vieillot) and the ivory-billed woodpecker (Campephilus principalis Linnaeus).
Because woodpeckers can be very persistent and are not easily driven from selected territories or pecking sites, any control effort should be started as soon as the problem begins. Positive results come easier before their territories are well established. Serious damage is more likely to occur to summer/vacation homes that are often vacant, since the attack can persist for long periods of time before discovered.
Exclusion is the best overall control technique. To prevent further damage to wood beneath the eaves, plastic bird netting can be installed from the gutter angled back to the siding below the damaged area. Metal sheeting (aluminum usually best) painted to match the siding can be installed over the area being attacked; hardware cloth can also be used but should be raised on 1″ (2.5 cm) wood spacers.
Occasionally repellents, such as bright aluminum/plastic strips, noise makers, and sticky/tacky gels, may give some relief.
Permits are required for the use of wooden-based rat snap traps. Nail the trap to the siding alongside the damage with the trigger downward. Bait the trap with walnut/almond/pecan nutmeats or suet. These traps are quite effective as is shooting which also requires a permit and an excellent marksperson to avoid liability/damage.
In general, decoys do not work. Although treating insect infested wood may have some merit, woodpeckers often attack sound and/or uninfested wood and hence such treatment is not appropriate.
What do Woodpeckers look like?
Introduction to Common Bed Bugs
This bug probably received its common name of bed bug from its close association with human sleeping beds where it often seeks refuge during daylight, only to come out to feed on the bed’s occupant(s) at night; they have been called by over 50 common names that include red coates, mahogany flats, and wall-lice, to name a few. The bed bug is an ectoparasite of primarily humans but will also attack poultry and other mammals and birds. It was introduced into the United States with the early colonists. It is found throughout the United States and the temperate regions of the world. Its’ association with humans has been documented to date back more than 3,300 years (1336 BC in Egypt).
In 2004, NPMA estimated a 500% increase in the preceding 3 years. The resurgence of bed bugs that started in the mid-1990s is probably due to a combination of factors such as the 5 that follow.
(1) Bed bugs are excellent hitch hikers and the United States in 1995 had 43 million international tourists visit, in 1999 the number was 48 million, and in 2000 it was up to 51 million; likewise, millions of Americans annually visit foreign countries.
(2) The greater use of integrated pest management techniques by pest management profes- sionals where infestations are treated in a targeted manner (e.g., baits for cockroaches) allows insects in untreated areas of the ecosystem to increase.
(3) Although mostly eliminated in the United States after World War II, bed bugs remained prevelant in Asia, Africa, Central and South America, and Europe where heavy reliance for about the last 15 years on pyrethroid pesticides for control measures selected for bed bug resistance and cross-resistance to pyrethroids, now found to be from several-hundred to several- thousand fold in some cases; most pesticides presently labeled for bed bugs are pyrethroids.
(4) The removal from the marketplace of several different classes of pesticides that previously had given very effective control and the removal of bed bugs from most remaining product labels because no need was perceived.
(5) The unfamiliarity of physicians and the public at large with bed bugs, which allows infestations to increase until the diagnosis/identification is corrected and proper treatment rendered.
Recognition of Common Bed Bugs
Adults about 3/16″ (4-5 mm) long; broadly oval and flat. Color brown to reddish brown (after feeding). Head with beak/proboscis 3-segmented, not extending beyond front coxae. Ocelli absent. Antenna 4-segmented, 3rd segment longer than 2nd or 4th. Pronotum with front margin deeply concave to receive head, with side margins greatly expanded forward to beyond eyes, pronotum more than 2.5 times as wide as long at its middle; fringe hairs on pronotum shorter than width of eye. Bases (coxae) of middle and hind legs widely separated; tarsi 3-segmented. Front wings vestigial, reduced to wing pads; with contiguous (touching) portions shorter than scutellum (triangular plate directly behind pronotum) in length. Body upper surface sparsely covered with short golden hairs (setae), usually shorter than diameter of 2nd antennal segment. Emit an “obnoxiously sweet” odor from scent glands.
Nymphs resemble adults but are smaller and paler in color; white just after molting and then light tan in color before feeding.
Similar Groups to Common Bed Bugs
(1) Tropical bed bug (Cimex hemipterus) with pronotum less than 2.5 times as wide as long at its middle; southern Florida.
(2) Bat bugs (C. adjunctus and C. pilosellus) with upper surface of body covered with long hairs (setae), length 1.5 or more times the diameter of the 2nd antennal segment, fringe hairs on pronotum longer than, or equal to, width of eye.
(3) Swallow bug (Oeciacus vicarius) with 3rd and 4th antennal segments equal in length.
(4) Poultry bug (Haematosiphon inodorus) with beak/proboscis extending back to hind coxae.
(5) Swift bug (Cimexopsis nyctalis) with bases (coxae) of middle and hind legs nearly touching and body bare, lacking hairs.
(6) Flat bugs (family Aradidae) with narrow wings, abdomen extending beyond them, beak/probosis 4-segmented, and tarsi 2-segmented.
Biology of Common Bed Bugs
Female bed bugs lay 1 -5 eggs per day with the 1/32″ (1 mm) long, white eggs being deposited individually in cracks or on rough surfaces and secured with a transparent cement for an average total of 200 eggs; maximum eggs per day is 12, with 541 for a lifetime. There are 5 nymphal instars with a blood meal required for each molt. About 3-10 minutes are required for each blood meal, during which saliva containing an anticoagulant is injected. Developmental time (egg to adult) takes 21 days at 86°F/30°C to 120 days at 65°F/18°C, with an additional 3 or 8 days respectively for oviposition to occur. The threshold for egg hatching, nymphal development, and adult activity is 55- 59°F/13-15°C. Below 61°F/16°C adults enter semihibernation and the thermal death point is 111-113°F/44-45°C. Without a blood meal, once-fed nymphs can survive an average of 51 days (range 28-73) at 81°F/27°C and 70-75% RH. Being poorly fed can greatly prolong the nymphal period (35-48 days to 158 days in one study). With normal feeding and reproductive cycles, individuals can live up to 316 days.
Humans are the preferred host of bed bugs and they tend to feed on any bare skin that is exposed while sleeping.
Although the bite of bed bugs is painless, many people develop an allergic reaction to the saliva injected by the bug as it feeds. A swelling usually results from feeding but there is no red spot such as is characteristic with flea bites. Swelling may be severe and extend beyond the immediate bite area in highly sensitive individuals. However, some individuals never develop a reaction to bites, and some after long exposure to bites eventually reach a point where they no longer have a reaction to bites.
Bed bugs have been found to be infected with some 25 different disease organisms. Survival time within the bed bug was found to be especially long (147-285 days) for the organisms of plague, relapsing fever, tularermia, and Q fever. However, although bed bugs have been suspect in the transmission of many diseases or disease organisms in humans, conclusive evidence of transmission is lacking. The principal medical concern is limited to the itching and secondary infections from scratching.
Habits of Common Bed Bugs
Bed bugs are efficient hitchhikers and easily transported. Once introduced, they are often spread throughout a building. They harbor in cracks and crevices during the day and come out to feed at night. The senior author has experienced hungry bed bugs becoming very active during the day and orientating to his presence when exposed to his normal breathing and body odors while he was taking images of the infestation.
In hotels/motels, the number one place for infestations is the backside of headboards mounted on walls; these must be removed for inspection. Typically, initial infestations of bed bugs are found associated with the bed such as around mattress buttons and beading, in boxsprings or their coverings, and in any crevice of a wooden bed frame, such as where members join. They are particularly fond of wood and fabrics as opposed to plastic and metal.
Eventually, other places are infested including wall hangings such as picture frames and mirrors, night stands, stuffed furniture (especially if used for sleeping), baseboards, floorboard cracks, behind loose wallpaper, light switches, door and window frames, curtains/drapes, under carpets between the tac-strip and baseboard, conduits, etc. Clutter is a bed bug’s best friend and must be eliminated. In heavier infestations, bed bugs may be found in telephones, radios/CD players, clocks, televisions, in items stored under beds, wall voids, electrical outlet boxes, attics, and other enclosed places. In addition, a few bugs and/or eggs can often be found in areas distant from the bed on the other side of the room. They will crawl distances in excess of 100 feet (30 m) to obtain a blood meal. If left untreated, the infestation will spread to adjoining rooms and/or apartments; think/inspect in 3 dimensions.
Because of their hitchhiking abilities, they can be introduced into a structure via used furniture or in the belongings of someone who has been living in or visiting a bed bug infested situation. Adults can survive for up to one year if they are well fed. In the absence of humans, bed bugs will feed on any warm-blooded animal including poultry, canaries, English sparrows, mice, rats, bats, and household pets such as guinea pigs and dogs. When the temperature falls below 61°F/16°C, adults enter semihibernation and can survive for months.
Bed bug infestations have been found in transportation vehicles such as boats, trains, airplanes, and buses as well as in movie theaters where they typically harborage in seats and associated frames.
Presently, most infestations are encountered in hotels/motels (all levels of prestige), youth hostels, shelters, and dormitories, probably because of the transient nature of occupation and student visitation habits in dormitories. In these situations, infestations may become widespread, but customer/resident complaints usually prevent them from becoming very severe before professional help is sought. Apartments and single-family residences are a distant second, but infestations here can build up to tremendous numbers before professional help is sought.
The primary clues to an infestation will be the presence of small red to reddish brown fecal spots clustered on surfaces near harborages, bed bug molt skins, their eggs or empty egg shells, and/or bed bugs themselves. In very heavy infestations, the characteristic obnoxiously sweet bed bug odor may be detected.
Control of Common Bed Bugs
A thorough inspection that may take several hours is indispensable; refer to the habits section above for suggestions. Treat any bed bugs found with an appropriately labeled pesticide; in general, aerosols and liquids are best, but dusts are better for under baseboards, the tac-strip area under carpets, and voids including outlet boxes and the inner framework of sofas and stuffed chairs. The proper use of steam has proven to be an effective means of control in certain situations such as mattresses, boxsprings, stuffed furniture, stuffed toys, etc., but depth of penetration can be a problem. Use the large nozzle, 1.5″ from the surface and move slowly.
Great care should be taken when treating mattresses, box springs, and upholstery to keep pesticide exposure to the customer to a minimum; allow for thorough drying before reuse. Infant’s and infirmed person’s bedding and bed frames should not be treated. If the customer is comfortable with the idea, mattresses and box springs can be encased in tight-sealing covers designed for house dust mite prevention or control. Otherwise, they should be replaced with uninfested items.
Infested items including linens and clothes should only be removed from a room once they are encased in a plastic bag to prevent spreading the infestation by bed bugs falling off during transport. A normal hot wash cycle will kill bed bugs. Running dry clothes or other items (non-washables such as backpacks, shoes, etc.) through a hot drier (as hot as the fabrics can withstand, but a minimum of 140ºF/60ºC) for 10 minutes kills all stages, but don’t run larger than half-loads. Wet clothes/loads need to be thoroughly/completely dried first, then run the drier hot (as hot as the fabrics can withstand, but a minimum of 140ºF/60ºC) for 10 minutes. If freezing is appropriate or desirable, hold the items at 27ºF/- 5ºC for 5 days in a non-defrosting kind of freezer. If a bed bug infestation is discovered when it is confined to 1 or 2 places, it can often be controlled with a single application to infested and adjoining areas, and/or by replacing the infested items; follow-up inspections should be scheduled at least monthly to be sure. For established infestations, several services will be required with 2-week intervals being the norm for the first 2 or 3 months depending on the severity of the infestation. In apartment buildings and hotels, it’s highly advisable to also inspect units to either side and above and below the infested unit(s), and treat as required.
In apartments, one study found that the boxsprings were the most heavily infested item (35%), mattresses (22%) and sofas/reclining chairs (23%) were about tied for second, and bedframes/headboards were third (13%). The other 7% were found in items such as inside a coffee maker and books, associated with walls, ceilings, and baseboards, in nightstands and dressers, which were often several feet away from the bed. The time spent was 1-2 man-hours on the initial and at least 1 hour (and often much more) on each follow-up visit. Especially on the initial, 2 people are required to lift, tear apart, and move furniture. In hotels/motels, headboards mounted on walls are usually the place of first infestation. Even though complaints should greatly diminish or stop after a few weeks of service, follow-up inspections are advisable for several months because it is extremely difficult to achieve 100% elimination. Remember, bed bugs are easily reintroduced, especially in communal or rental units/situations.
In cases where the infestation is severe, high pyrethroid resistance is established, when peace-of-mind must be addressed, and/or when quick elimination is required, fumigation should be seriously considered. Fumigation may at first appear to be costly, but when every cost or loss is added up, it may be very cost effective.
What do Common Bed Bugs look like?
Introduction to Cat Fleas
Fleas are one of the more important groups of insect pests because they not only cause discomfort by biting, but they can transmit several diseases such as plague and murine typhus. Cat fleas are the most common domestic flea. In the United States, they are commonly found on both cats and dogs. Cat fleas are found throughout the United States and the rest of the world.
Recognition of Cat Fleas
Adults about 1/8″ (2.5 mm) long. Body laterally flattened (side to side); wingless. Color brownish black to black, but reddish black when full of blood. Female’s head twice as long as high. Compound eyes well developed. Both genal and pronotal combs present, each composed of 16 spines, and genal comb’s first 2 anterior spines of about equal length. Femur of hind leg with 7-10 bristles on inner side. Abdominal terga (dorsal plate of segments) 2-6 with a single row of bristles. In addition, antennae short, 3- segmented; ocelli lacking; legs long, coxae large, tarsi 5-segmented; usually jumping insects; mouthparts piercing-sucking with well-developed palps. Mature larvae about twice the adult length (1/4″/3-5.2mm). Larvae whitish, slender, eyeless, and legless. With a well-developed head. Anal struts/hooks 2, small. With moderately long, backward-projecting hairs (setae) encircling each segment. Last abdominal segment (10th) with 3 ventrolateral hairs (setae).
Similar Groups to Cat Fleas
(1) European mouse flea (Leptopsylla segnis) has genal comb with only 4 spines.
(2) Rabbit flea (Cediopsylla simplex) with genal spines oriented vertically (vs. horizontal), comb spines with blunt/rounded ends.
(3) Dog flea (Ctenocephalides canis) with head length less than twice height, genal comb with spine I (anterior most) distinctly shorter than spine II (adjacent spine to posterior/ rear), hind leg femur with 10-13 bristles on inner side.
(4) Other fleas (various families) lack having both pronotal and genal combs or if both pronotal and genal combs present, then either have abdominal combs or have fewer than 16 spines in pronotal comb (dog flea with 16 pronotal spines, see above).
Biology of Cat Fleas
Females lay 4-8 eggs after each blood meal, laying some 400-500 during their lifetime. The eggs are smooth and not glued/stuck to the hairs or body but are deposited on or between hairs, or in the nest or bedding material. Hence, eggs deposited on the animal either fall or are shaken off, and are frequently found in cracks and crevices where pets sleep or frequent. Eggs are oval, whitish, and about 1/64″ (0.5 mm) long. They usually hatch in about 2 days (range 1-12 days).
Flea larvae move about using the setal rings and abdominal struts/hooks. They have chewing mouthparts and feed on organic debris but almost all require dried fecal blood in order to complete development; they do not bite but feed on adult flea fecal blood. Larvae require high relative humidity (45-95%) and 1-2 weeks to several months to go through 3 instars. Last instar larvae then spin a cocoon and incorporate surrounding debris on its surface which provides camouflage. Under favorable conditions, the pupal stage may last 4-14 days or up to a year under harsh conditions. The pre-emerged adult remains in the cocoon for up to 20 weeks, where it is protected from adverse conditions, including pesticides. Adults are stimulated to emerge from the cocoon by mechanical depression of the cocoon, an increase in temperature, and possibly vibrations. Larvae and pupae are typically found where the animal sleeps or frequents.
Adults usually begin to seek a blood meal on the second day after emergence, but can live for several months on their stored body fat. Adults, unlike many other fleas, once on a host tend to spend all of their time on the host, feeding, mating, and laying eggs, unless dislodged. Although they have a preferred host, they will readily bite and can survive using other species as hosts. Depending on conditions, adults usually live only several days because normal cat grooming removes up to 50% of the fleas; otherwise, they can survive about a year.
Cat fleas may transmit plague. There is very strong circumstantial evidence that they may transmit murine typhus. Cat fleas serve as intermediate hosts of the dog tapeworm, Dipylidium canninum (Linnaeus), and the rodent tapeworm, Hymenolepis diminuta (Rudolphi). These tapeworms occasionally infest humans, especially very young children. The dog tapeworm commonly infests cats that spend time outdoors.
Habits of Cat Fleas
It is not necessary to have pets in the building in order to have fleas present. Since fleas can jump about 6″ (15 cm) vertically, they can easily hitch a ride on shoes, trousers, etc.
Many vacationers who may have been unaware of the few adult fleas present, are often greeted and severely attacked by fleas upon their return. This can occur even if the building has been vacant of animals and people for as long as 6 months or so. This situation can occur because of the potentially long pupal period, adults can live for months without food, and because fleas have not been removed via normal vacuuming. Also, fleas are normally removed from the interior environment by taking up residence on the pet(s).
Fleas are typically found where animals sleep or frequent, including along their usual avenue of travel, because this is where eggs and adult fecal blood accumulate. Most larvae will be found in similar places but especially in areas with high moisture which is necessary for their survival. Pupae will be found in the same situations as larvae. Such places include both indoor and outdoor situations. Cat fleas are also found on other urban hosts such as opossum, fox, mongoose, and occasionally rats.
Flea larvae die at relative humidities below 45% and above 95%, and hence, are rarely found outdoors in arid climates. Larvae fail to develop at temperatures below 55°F (13°C) and at or above 95°F (35°C).
Control of Cat Fleas
Flea control is a 4-part process.
- Wild animals such as rodents, opossums, etc., which are nesting in or frequently visiting the structure must be prevented from entering the structure and controlled with appropriate trapping devices or baits.
- If the pet has fleas at the time of treatment, the pet owner must arrange for the pet to be treated. Treatment may be done by a veterinarian, grooming parlor personnel, or by the pet owner, but must be done on the day of treatment and either before or while the premises are being treated.
- Indoor control. The homeowner or occupant must do the following just before the flea treatment: remove all items such as toys and pillows off the floor or carpet; remove all articles from under beds, on closet floors, and from under furniture; vacuum all upholstered furniture, floors, and carpeting, paying particular attention to the foot of the furniture on which the pet rests, under furniture, and wall-floor junctions. The vacuum bag must be immediately removed and put into a plastic garbage bag, the top sealed, and then placed in an outside garbage receptacle or burned. Thoroughly clean all areas frequented by cats, e.g. table tops, refrigerator tops, window sills, counters, etc. Cover aquariums and turn off the pumps prior to the treatment. Be sure to remove all pets, including birds. The pest management professional’s treatment consists of applying an appropriately labeled pesticide and/or IGR as per label instructions with thoroughness being the key to success. It is recommended that an IGR (insect growth regulator) be used on the initial treatment and reapplied as per label instructions every 3-6 months throughout the flea season. For problem accounts, it is recommended that the IGR alone be applied prior to the beginning of the next flea season as a preventative measure. Regardless, after any carpet and/or floor treatment, do not allow humans or pets back into the house until the treatment has completely dried. This will prevent pesticide pickup and possible staining from dirt being brought in contact with the damp carpet. Also, advise the occupant(s) to ventilate the house upon re-entry. Since vacuuming has little effect on residual deposits, advise the customer to vacuum several times during the first 7-10 days after treatment. This will help reduce the emerging fleas and callbacks. Be aware that some pesticide sprays (microencapsulated formulations) tend to stimulate fleas to emerge from their cocoon.
- Outside control. Minimally, spot treatment should be done. This consists of treating with an appropriately labeled pesticide and light-stable IGR, every place the animal rests, naps, or sleeps which are typically cool areas such as next to the building’s foundation, porch, etc., or under a bush or tree. In addition, band treatment is often helpful, especially if overall treatment is not going to be done. Band treatment is done with an appropriately labeled pesticide which is applied in a 6-10 foot band around the perimeter of the building. For dogs confined to a fenced-in yard, also treat the 3-4 feet adjacent to the fence on the side to which the dog has access. If the infestation is severe, overall yard treatment may be required and an appropriately labeled pesticide should be used. Wettable powder and microencapsulated formulations are particularly effective outdoors. In 2006, it was estimated that $2.8 billion is spent annually on flea-related veterinarian bills. Pet owners annually spend an estimated $1.6 billion for flea treatment via pet groomers, $4 billion for over-the-counter treatments, and $348 million for PMP control services.
What do Cat Fleas look like?
INTRODUCTION
Their common name comes from dogs being one of their 2 favorite hosts, with rabbits being the other. Like other fleas found in homes, they cause discomfort by biting, but they can also transmit several diseases such as plague and murine typhus. Dog fleas are found throughout the United States and the rest of the world.
RECOGNITION
Adults about 1/8″ (2.5 mm). Body laterally flattened (side to side); wingless. Color brownish black to black, but reddish black when full of blood. Female’s head less than twice as long as high. Compound eyes well developed. Both genal and pronotal combs present, each composed of 16 spines, and genal comb’s spine I (anterior most) shorter than spine II (adjacent spine to posterior/rear). Femur of hind leg with 10-13 bristles on inner side. Abdominal terga (dorsal plates) 2-6 with a single row of bristles. In addition, antennae short, 3-segmented; ocelli lacking; legs long, coxae large, tarsi 5-segmented; usually jumping insects; mouthparts piercing-sucking with well-developed palps.
Mature larvae about 1/8-1/4″ (3-5.2 mm) long. Larvae whitish, slender, eyeless, and legless. With a well-developed head. Anal struts/hooks 2, small. With moderately long, backward-projecting hairs (setae) encircling each segment. Last abdominal segment (10th) with 3 ventrolateral hairs (setae). Description is same as for cat and oriental rat fleas.
SIMILAR GROUPS
(1) European mouse flea (Leptopsylla segnis) has genal comb with only 4 spines.
(2) Rabbit flea (Cediopsylla simplex) with genal spines oriented vertically (vs. horizontal), comb spines with blunt/rounded ends.
(3) Cat flea (Ctenocephalides fells) with head twice as long as high, genal comb with 1st 2 anterior spines of about equal length, and hind femur with 7-10 bristles on inner side.
(4) Other fleas (various families) lack having both pronotal and genal combs or if both present, then either have abdominal combs or have fewer than 16 spines in pronotal comb (cat flea with 16 pronotal spines, see above).
BIOLOGY
Females lay 4-8 eggs after each blood meal, laying some 400-500 during their lifetime. The eggs are not glued/stuck to the hairs or body but are deposited on or between hairs, or in the nest or bedding material. Hence, eggs deposited on the animal either fall or are shaken off, and are frequently found in cracks and crevices where pets sleep or frequent. Eggs are oval, whitish, and about 1/64″ (0.5 mm) long. They usually hatch in 1-12 days.
Flea larvae move about using the setal rings and abdominal struts/hooks. They have chewing mouthparts and feed on organic debris but almost all require dried fecal blood in order to complete development; they do not bite but feed on adult flea fecal blood. Larvae require high relative humidity (45-95%) and 1-2 weeks to several months to go through 3 instars. Last instar larvae spin a cocoon and incorporate surrounding debris on its surface which provides camouflage. Under favorable conditions, the pupal stage may last 4-14 days or maybe up to a year under harsh conditions. The pre-emerged adult remains in the cocoon for up to 20 weeks, where it is protected from adverse conditions, including pesticides; it can survive here for several months on stored body fat. Adults are stimulated to emerge from the cocoon by mechanical depression of the cocoon, an increase in temperature and/or carbon dioxide, and possibly vibrations. Larvae and pupae are typically found where an animal sleeps or frequents.
Adults usually begin to seek a blood meal on the second day after emergence. Once on a host, they tend to spend all of their time on the host, feeding, mating, and laying eggs, unless dislodged. Although they have a preferred host, they will readily bite and can survive using other species as hosts. Depending on conditions, adults usually live only several days because normal dog grooming removes up to 50% or more of the fleas; otherwise, they can survive for several months.
Dog fleas are known to be vectors of the disease organisms causing both plague and murine typhus. Dog fleas can also serve as an intermediate host for the dog tapeworm, Dipylidium caninum (Linnaeus), and the rodent tapeworm, Hymenolepis diminuta (Rudolphi). These tapeworms occasionally infest humans, particularly very young children.
HABITS
It is not necessary to have pets in the building in order to have fleas present. Since fleas can jump about 6″ (15 cm) vertically, they can easily hitch a ride on shoes, trousers, etc.
Many vacationers who may have been unaware of the few adult fleas present in their home, are often greeted and severely attacked by fleas upon their return. Fleas can be present even if the building has been vacant of animals and people for as long as 6 months or so. This situation can occur because of the potentially long pupal period, adults can live for months without food, and because fleas have not been removed via normal vacuuming. Also, fleas are normally removed from the interior environment by taking up residence on the pet(s).
Fleas are typically found where animals sleep or frequent, including along their usual avenue of travel, because this is where eggs and adult fecal blood accumulate. Most larvae will be found in similar places but especially in areas with high moisture which is necessary for their survival. Pupae will be found in the same situations as larvae. Such places include both indoor and outdoor situations. Dog fleas are also found on other urban hosts such as rabbit, spotted skunk, opossum, occasionally rats, and rarely cats.
Flea larvae die at relative humidities below 45% and above 95%, and hence, are rarely found outdoors in arid climates. Larvae fail to develop at temperatures below 55°F (13°C) and at or above 95°F (35°C).
CONTROL
Flea control is a 4-part process.
- Wild animals such as rodents, opossums, etc., which are nesting in or frequently visiting the structure must be prevented from entering the structure and controlled with appropriate trapping devices or baits.
- If the pet has fleas at the time of treatment, the pet owner must arrange for the pet to be treated. Treatment may be done by a veterinarian, grooming parlor personnel, or by the pet owner, but must be done on the day of treatment and either before or while the premises are being treated.
- Indoor control. The homeowner or occupant must do the following just before the flea treatment: remove all items such as toys and pillows off the floor or carpet; remove all articles from under beds, on closet floors, and from under furniture; vacuum all upholstered furniture, floors, and carpeting, paying particular attention to the foot of the furniture on which the pet rests, under furniture, and wall-floor junctions. The vacuum bag must be immediately removed and put into a plastic garbage bag, the top sealed, and then placed in an outside garbage receptacle or burned. Thoroughly clean all areas frequented by cats, e.g. table tops, refrigerator tops, window sills, counters, etc. Cover aquariums and turn off the pumps prior to the treatment. Be sure to remove all pets, including birds. The pest management professional’s treatment consists of applying an appropriately labeled pesticide and/or IGR as per label instructions with thoroughness being the key to success. It is recommended that an IGR (insect growth regulator) be used on the initial treatment and reapplied as per label instructions every 3-6 months throughout the flea season. For problem accounts, it is recommended that the IGR alone be applied prior to the beginning of the next flea season as a preventative measure. Regardless, after any carpet and/or floor treatment, do not allow humans or pets back into the house until the treatment has completely dried. This will prevent pesticide pickup and possible staining from dirt being brought in contact with the damp carpet. Also, advise the occupant(s) to ventilate the house upon re-entry. Since vacuuming has little effect on residual deposits, advise the customer to vacuum several times during the first 7-10 days after treatment. This will help reduce the emerging fleas and callbacks. Be aware that some pesticide sprays (microencapsulated formulations) tend to stimulate fleas to emerge from their cocoon.
- Outside control. Minimally, spot treatment should be done. This consists of treating with an appropriately labeled pesticide and light-stable IGR, every place the animal rests, naps, or sleeps which are typically cool areas such as next to the building’s foundation, porch, etc., or under a bush or tree. For dogs confined to a fenced-in yard, treat the 3-4 feet adjacent to the fence on the side to which the dog has access. Band treatment is helpful, especially if overall treatment is not going to be done. Band treatment is done with an appropriately labeled pesticide which is applied in a 6-10 foot band around the perimeter of the building. If the infestation is severe, overall yard treatment may be required and an appropriately labeled pesticide should be used. Wettable powder and microencapsulated formulations are particularly effective outdoors. Note that if the pet is on Proban, Prospot or similar product, use of such a product should be discontinued one week before treatment and until one week after treatment.
What do Dog Fleas look like?
Introduction to Deer and Horse Flies
These flies probably received the common name of deer flies (Chrysops spp.) and horse flies (Tabanus spp.) because they are notorious pests of deer and horses respectively, and of other mammals. They are pests primarily in suburban and rural areas where both their breeding sites of in or near bodies of water and mammal hosts are more abundant. Some species are vectors of disease organisms to humans and other mammals, but in the U.S. most vectored diseases involve livestock. They are found throughout North America, with about 350 species occurring here.
Recognition of Deer and Horse Flies
Adults medium to large, about 1/4-1 1/8″ (6-30 mm) long; without bristles, most stout-bodied. Color ranges from black to pale yellow, usually with stripes on abdomen, often with bright green or purple eyes. Head with compound eyes very large, separated (dichoptic) in females but touching (holoptic) in males. Antenna 3- segmented, 3rd segment enlarged basally, with terminal portion elongate and annulized (subdivided by rings into 2-8 sections). Wing with calypter (lobe at base on rear margin) large, veins R4 and R5 divergent, enclosing wing tip, 4 or 5 posterior cells present. In addition
- Deer flies (Chrysops spp.) smaller, about 1/4-1/2″ (6-12 mm) long; color black or brownish, usually with dark areas on wings, eyes usually with spots, 3rd antennal segment lacks a basal toothlike process; and hind tibiae with apical spurs.
- Horse flies (Tabanus spp.) larger, about 3/8-1 1/8″ (10-30 mm) long; color usually gray or blackish, wings usually lacking dark areas but some species with wings entirely dark, eyes often with horizontal stripes; 3rd antennal segment with a basal toothlike process; and hind tibiae lack apical spurs.
Similar Groups to Deer and Horse Flies
(1) Snipe flies (Rhagionidae) have antennae with 3rd segment more or less rounded, bearing a long slender terminal style (prolongation), and wings with calypters (lobes at base on rear margin) small or vertigial.
(2) Soldier flies (Stratiomyidae) have antennae with 3rd segment rounded or elongate and wing with branches of radius (R4+R5) crowded towards front, with R5 ending in front of wing tip.
(3) Other flies of public health importance with 3-segmented antennae have fewer than 4 posterior cells in wings.
Representative Species of Deer and Horse Flies
- Chrysops callidus Osten Sacken. Length about 1/4-3/8″ (7-9 mm); color black with mid-dorsal yellow triangles on abdomen and large pale yellow spots on sides near base, wings with characteristic brown markings; widespread in United States.
- Chrysops carbonarius Walker. Length about 1/4-3/8″ (7-9 mm); color black with yellowish gray and greenish gray markings, wings with characteristic black markings; widespread in United States.
- Chrysops discalis Williston. Length about 3/8″ (8-10.5 mm); color of female gray to yellowish gray with black spots on abdomen, male mostly black with yellowish gray spots on abdomen, wings with characteristic brown pattern; distributed in western U.S.
- Chrysops flavidus Wiedemann. Length about 3/8-1/2″ (8-12 mm); color brown to black with light tan markings, wings with characteristic black markings; found throughout eastern U.S.
- Black horse fly, Tabanus atratus Fabricius. Length about 3/4-1″ (20-25 mm); color entirely black including wings; found throughout United States.
- Greenhead, Tabanus americanus Forester. Length about 7/8-1 1/8″ (22-28 mm); color with eyes bright green, thorax and abdomen reddish brown, wings with markings only along front edge; found throughout eastern U.S. west to Mississippi River and eastern Texas, also southern Canada.
- Striped horse fly, Tabanus lineola Fabricius. Length about 1/2-5/8″ (12-15 mm); color with thorax striped brown and gray, abdomen brown or black above with 3 gray stripes; found throughout eastern U.S. and in Texas.
- Western black horse fly, Tabanus punctifer Osten Sacken. Length about 3/4-7/8″ (18-22 mm); color black, male with thorax white on rear and side margins, female with thorax all pale and hairy, wings lightly smoky with single dark spot in outer portion; found in Pacific Northwest, Montana, Wyoming, Colorado, California, and southwestern U.S.
Biology of Deer and Horse Flies
Eggs are laid in masses of 100-1,000 eggs covered with a jellylike material on leaves, rocks, or debris overhanging water or on moist areas; deer flies often lay single layer masses, horse flies lay 3-4 layer masses. Upon hatching the larvae fall into the water or onto moist soil. In general, the larvae of horse flies are carnivorous and cannibalistic, feeding on insect larvae, snails, earthworms, etc. whereas, larvae of deer flies feed on decaying organic matter (detritovores). They go through 4-9 instars. Larvae move to the drier fringe areas of their habitat to pupate, aquatic larvae to decaying vegetation at water’s edge and soil dwellers to the drier edges of their habitat. Developmental time (egg to adult) may require 3 months to 3 years. Adults live about 3-4 weeks, and produce 5-6 batches of eggs. Most species overwinter as larvae.
The mouthparts are for tearing and lapping, not piercing. Both sexes feed on nectar, but females require a blood meal for egg laying.
In the U.S. only the deer fly, Chrysops discalis, is a vector of disease to humans. In this case it is the bacterium Francisella tularensis (McCoy & Chapin) which causes tularemia that is transmitted from rabbits, hares, and other rodents. After biting an infected animal, they can transmit the disease for about 5 days. Apparently the transmission is mechanical. Tabanids also mechanically transmit a number of diseases to domesticated animals such as anthrax, California encephalitis, western equine encephalitis, etc.
Habits of Deer and Horse Flies
Most tabanid flies are woodland or forest dwellers. Most species feed during full daylight and are most evident on windless, hot, sunny days. In general, larvae of horse flies (Tabanusspp.) develop in wet soil close to bodies of water and the larvae of deer flies (Chrysops spp.) develop in wet mud often in semi-submerged situations. However some species are aquatic, living in rapidly flowing streams to stagnant ponds and some only in bogs, while others live in relatively dry soil or in rotten wood.
Adults are strong fliers and are capable of flying over 31 mi (50 km). However they generally do not disperse widely, usually less than 2 mi (3 km). Moving and dark objects are most often attacked. They often rest on paths and roads, especially in wooded areas. A slight drop in temperature or increase in wind will greatly reduce the numbers flying.
The females can enter structures in considerable numbers and then congregate at the windows since they are attracted to light. Both sexes of many species occasionally come to lights at night.
Control of Deer and Horse Flies
Outside control of horse flies and deer flies is not practical because of the larval developmental sites, the distance adults can travel, and because adults in general do not continually reuse the same resting surfaces. During outside activities, the wearing of light-colored clothing and insect repellents can reduce attack by horse flies and deer flies.
If these tabanids are entering structures, the best method of control is exclusion. This includes screening all doors and windows. Self-closing doors are helpful. In commercial structures, dock doors should be equipped with an interior screen door that is lowered when the dock door is up to permit ventilation, but the dock is not in use. Non-public exterior doors should be equipped with air curtains which come on automatically whenever the door is opened to help prevent entry. Properly placed insect light traps will help eliminate tabanids once they enter the structure.
What do Deer and Horse Flies look like?
Introduction to Mosquitos
Mosquitoes are well known by most people because of their pesky biting habit. Of greater concern, they are very important as vectors of numerous human diseases such as West Nile virus, malaria, yellow fever, filariasis, dengue, and encephalitis. Mosquitoes are distributed throughout the world, including the United States.
Recognition of Mosquitos
Adults about 1/8-3/8″ (3-9 mm) long; body and legs usually covered with scales. Color mostly gray to dark, some marked with white, silver, green, or iridescent blue scales. Head with proboscis/beak long; ocelli absent. Antennae 15- segmented, plumose (feathery) in male, hairy in female. Wings 2 in number, long, narrow, with scales along veins and wing margin; outer part of wing with an unforked vein between 2 forked veins.
The adults of the 4 most common genera of mosquitoes can be distinguished as follows:
- Anopheles with palps about as long as proboscis/beak and rests with body and proboscis in one plane or axis which is at an angle to the surface.
- Aedes and Ochlerotatus with palps much shorter than proboscis and rests with body and proboscis in 2 different planes (at an obtuse angle to each other) and body resting on the surface.
- Culex with palps much shorter than proboscis and rests with body and proboscis in 2 different planes and body up off but parallel to the surface.
Larvae with head and thorax wider than abdomen, thorax of 3 fused segments and widest. Antenna 1-segmented. Mouthparts with labial brush usually consisting of numerous fine hairs, sometimes reduced to about 10 stout curved rods. Abdominal segment 8 usually with a breathing/respiratory tube. Abdominal segment 10 (last segment) with hardened dorsal plate or ring, with long dorsal hairs and prominent ventral brush, and with 2 or 4 membraneous anal papillae (fingerlike projections).
Similar Groups to Mosquitos
(1) Dixid midges (Dixidae) with wings lacking scales and body bare.
(2) Midges (Chironomidae) with wings lacking scales, front tarsi usually lengthened (very long), male antennae generally plumose (feathery), and proboscis (beak) short.
(3) Crane flies (Tipulidae) with wings lacking scales, body bare, legs very long, and usually much larger (3/8-1″/10-25 mm).
(4) Phantom crane flies (Ptychopteridae) with wings lacking scales.
Representative Species of Mosquitos
- Yellowfever mosquito, Aedes aegypti (Linnaeus). Adult dark brown to black with silvery white markings, identifying marks include dorsum of thorax with 2 outer curved and 2 median parallel marks forming a lyre-shaped pattern, tarsal segments ringed with white only on basal portion of segments, and abdomen with a dorsal narrow white basal band on each segment; wing length about 1/8″ (3.5 mm); breed in shaded artificial containers; occurs in southern states where nights are above 68°F/20°C, but not in California.
- Asian tiger or forest day mosquito, Aedes albopictus (Skuse). Adult dark to black with silvery white markings, identifying marks include dorsum of thorax with a single median silver-white stripe, tarsal segments ringed with white, and abdominal segments with a narrow dorsal white basal band; wing length about 1/8″ (3.5 mm); breed in artificial containers; found in eastern, midwestern, and southern United States.
- Floodwater mosquito, Ochlerotatus [formerly Aedes] stictcus (Meigen). Adult dark to black with whitish markings, identifying marks include head and thorax gray, thorax with darker longitudinal stripes, wings black scaled except costa and subcosta with white scales intermixed, legs speckled with white but no white rings, and abdominal segments with a narrow dorsal white basal band; wing length about 1/8″ (4 mm); breed in flood pools; distributed throughout the United States.
- Eastern saltmarsh or saltmarsh mosquito, Ochlerotatus [formerly Aedes] sollicitans (Walker). Adults golden brown with golden yellow or white markings, identifying marks include black proboscis/beak with wide white band near middle, black palps tipped with white, dorsum of thorax with darker brown areas, tarsal segments with narrow white basal ring, hind tarsal 1st segment with median yellow ring and 5th/last segment largely white, abdominal segments with dorsal yellowish narrow basal band and wider median longitudinal stripe and with white lateral/side markings; wing length about 3/16″ (4.5 mm); breed in salt marshes and saline areas; occurs in eastern and Gulf coastal areas from New Jersey to Texas and in inland saline areas.
- Vexans or inland floodwater mosquito, Aedes vexans (Meigen). Adult golden brown to brown with white to light gray markings, identifying marks include short palps with a few white scales at tip, all tarsal segments with narrow white basal ring, abdominal segments with dorsal white basal band notched in center, sometimes separating band into 2 parts, and 7th (terminal/last) abdominal segment with white only at tip if present; wing length about 3/16″ (4.5 mm); breed in temporary pools; found throughout the United States.
- Common malaria mosquito, Anopheles quadrimaculatus Say. Adults dark brown, legs lack bands and wings with only dark scales, each wing with 4 patches/spots of dark scales; palps as long as proboscis/beak; body and proboscis in one plane/axis when feeding; breed in permanent freshwater sites; found east of Rocky Mountains.
- Northern house mosquito, Culex pipiens Linnaeus. Adults brownish with white or gray markings, identifying marks include legs dark or black and lack bands but femora cream with dorsal or outer portions dark and abdominal segments with broad dorsal basal white band widest along midline and broadly jointed to lateral patches; wing length about 1/8″ (3.5 mm); breed in artificial containers, ditches, storm sewer catch basins, and polluted water; occurs throughout the northern states and as far south as Oklahoma and Georgia.
- Southern house mosquito, Culex quinquefasciatus Say. Adults similar in almost all respects to C. pipiens except abdominal basal white bands narrowly joined or disconnected from lateral patches; breeding sites similar to those of C. pipiens; occurs throughout the southern states and as far north as Nebraska, Iowa, Illinois, and Ohio.
- Encephalitis mosquito, Culex tarsalis Coquillett. Adults brown with white or gray markings, identifying marks include proboscis/beak with white ring near middle, tarsal segments with white rings, and femora and tibiae each with a longitudinal white line or row of white spots on outer surface; wing length about 3/16″ (4.5 mm); breed in temporary pools; throughout United States except for approximately eastern Michigan to eastern North Carolina and eastward.
Biology of Mosqutios
Mosquitoes are commonly separated into 3 groups based on where and how their eggs are laid. After a blood meal, the female will lay her eggs:
(1) singly on water, eggs with floats, usually hatch within a few days, e.g. Anopheles;
(2) in rafts on water with up to 100+ eggs per raft, usually hatch within a few days, e.g. Culex; and
(3) singly in semi-dry places such as moist soil near water, do not hatch until water has risen and inundated them, can lie dormant for 3-5 years, e.g. Aedes and Ochlerotatus.
With water present, eggs hatch in a few days into larvae which are commonly called wig- glers because of their jerky movements. All larvae live in water and go through 4 instars and 4 molts. Larvae of most species (e.g. Aedes, Culex, Ochlerotatus, etc.) take in air through a breathing tube (siphon) located on the 8th abdominal segment which penetrates the water surface while they float at an angle just below the surface. Other species (e.g. Anopheles) have a spiracular plate on the 8th abdominal segment which penetrates the surface while they float parallel to and just below the surface, their buoyancy enhanced by clusters of float hairs (palmate hairs) on some abdominal segments.
With their 4th molt, the larvae become pupae which are commonly called tumblers. The pupae live in water and are very active. The pupae of most species breathe through a pair of respiratory trumpets located on the dorsal thoracic surface which penetrate the water surface while they float just below the surface. At the end of the pupal stage, while at the water’s surface, the pupal skin splits open and the adult works its way out and onto the surface of the water, briefly dries and flies away. Developmental time (egg to adult) is usually about 10-14 days; eggs hatch in 1-3 days to 5 years, larval stage lasts 7 days to weeks, and pupal stage takes 2-4 days to a few weeks. Adult females may live up to 1-2 months (males about 6-7 days) in the summer or for 6+ months if they overwinter.
Mosquitoes serve as vectors of many important diseases affecting humans including West Nile virus, malaria, yellow fever, dengue fever, filariasis, and encephalitis. Refer to the chart entitled “Biological Data on Medically Important Mosquitoes in the U.S.” (page 3.18.5) for a summary of such diseases. Also of interest is the dog heartworm (Dirofilaria immitis (Leidy)) which is a common mosquito-transmitted filarial parasite of dogs and is a serious problem from Minnesota to Illinois to Texas and eastward.
Habits of Mosquitos
Mosquitoes have adapted to almost every kind of aquatic situation such as permanent ponds and marshes, temporary flood waters or woodland pools, drainage ditches, and water contained in tree holes, leaves of plants, or artificial containers. The exceptions are flowing streams and the open waters of large streams, rivers, lakes, seas, and oceans. The number of generations per year ranges from 1 where the eggs require cold before hatching (e.g. some Anopheles), to many in warm climates where most breed continuously.
The larvae of most species feed on small aquatic organisms and organic debris which they strain out of the water with a series of oral brushes. Although quite active, the pupae do not feed. The adult males feed on nectar. Although the adult female also feeds on nectar, females of most species require a blood meal before they can lay fertile eggs. Females require 2+ days to digest a blood meal, lay a batch of eggs, and then seek another blood meal.
The flight range of mosquitoes varies with the species, temperature, wind direction, time of year, and distance to blood meal sources. For various species of Aedes and Ochlerotatus (for 7 species formerly in Aedes, see table page 3.18.5), the range for recaptured marked females was from 18 mi (29 km) along coastal Georgia to 110 mi (177 km) at sea off the coast of North Carolina. These records probably represent females that got caught up in wind currents because their normal flight ranges are much shorter, about 5-10 mi (8-16/km).
The time of day in which biting occurs varies with the species. Most medically important species bite at dusk and dawn (crepuscular) and also during the night (nocturnal), e.g. the vexans mosquito (Aedes vexans), the southern house mosquito (Culex quinquefasciatus), and the encephalitis mosquito (Culex tarsalis), whereas others bite only at dusk and dawn such as the eastern saltmarsh mosquito (Ochlerotatus sollicitans). Several species of medical importance bite only during the daytime (diurnal) such as the Asian tiger mosquito (Aedes albopictus), and one species, the yellowfever mosquito (Aedes aegypti), bites during the day but also at dawn and dusk. Some species which normally do not bite during daytime will do so if disturbed, for instance by someone walking through high grass on which they are harboring.
Control of Mosquitos
Mosquito control begins with an accurate and thorough assessment of the problem through surveillance and then using the control measures best suited to the situation. Control measures may include one or a combination of techniques to:
(1) eliminate mosquito-producing areas via habitat modification;
(2) control mosquito larvae via pesticides, insect growth regulators (IGR’s), biologicals, monomolecular films, and/or predatory fish; and
(3) control of adults via ULV pesticide applications. For success, control efforts must not be dictated by political jurisdictions but instead by mosquito biology and distribution.
On the household level, relief can be achieved by preventing entry into structures via proper screening and sealing, the application of appropriately labeled residuals to resting surfaces, and ULV treatment to infested rooms. On the personal level, the use of repellents is quite effective. In areas of heavy infestation, full-head nets (similar to bee veils) are useful when outdoors and mosquito nets are useful when/where sleeping.
It should be mentioned that keeping gutters free-flowing, and emptying weekly or eliminating completely any containers which hold water on one’s own property can be of great help in reducing the number of local mosquitoes. This is especially true for mosquitoes which live in close association with humans and have short flight ranges.
What do Mosquitos look like?
Introduction of the American Dog Tick
This tick’s common name comes from the fact that it is only found in North America and that domestic dogs are the favorite host of the adults. Although not a structural pest, it is commonly found on dogs and readily attacks humans. It is of medical importance because it vectors the causal organisms of Rocky Mountain spotted fever and tularemia, and also causes tick paralysis. It is found throughout the United States except for the area of the Rocky Mountains, and in Canada and Mexico.
Recognition of the American Dog Tick
Unengorged adult female about 3/16″ (5 mm) long, male slightly smaller (about 1/8″/3.6 mm); engorged female up to about 5/8″ (15 mm) long, 3/8″ (10 mm) wide. Body oval, dorsoventrally flattened (top to bottom). Color brown with whitish to grayish markings often with silvery hue (ornamentation) on scutum (dorsal shield). Scutum (dorsal shield just behind mouthparts) restricted to front half of dorsum in female, almost completely covers dorsum in male except for festoons. Eyes on margin of scutum. Capitulum (mouthparts and their base) visible from above; basis capituli (base for mouthparts) rectangular with sides not laterally produced/angular; about as long as mouthparts; 2nd segment of palpi about as long as wide, not laterally produced. Abdominal festoons (rectangular areas divided by grooves along posterior margin) 11 in number; anal grove present, posterior to anus. Spiracular plate (ventral/bottom, near margin just behind 4th coxae, 1 pair) broad, usually with blunt process reaching dorsum, goblets (round structures) very small and numerous.
Both larvae (6 legs) and nymphs (8 legs) with red markings near eyes and lack white on scutum; unengorged 1st instar larvae about 1/64″ (0.59-0.64 mm) long, yellow, becoming gray to black when engorged; unengorged 2nd instar nymphs about 1/32″ (0.9 mm) long, pale yellowish brown, becoming slate gray when engorged.
Similar Groups to the American Dog Tick
(1) Rocky Mountain wood tick (Dermacentor andersoni) with spiracular plate goblets (round structures) moderate in size and number, found in Rocky Mountain area only.
(2) Winter tick (Dermacentor albipictus) and brown winter tick (Dermacentor nigrolineatus) with spiracular plate oval, lacking prolongation, and goblets few and large; in addition, brown winter tick scutum (dorsal shield just behind mouthparts) with little or no whitish/grayish markings.
(3) Pacific Coast tick (Dermacentor occidentalis) with posterior/rear lateral extensions of basis capituli (base for mouthparts) long, length equal to or greater than width.
(4) Tropical horse tick (Anocentor nitens) with 7 abdominal festoons (rectangular areas divided by grooves along posterior margin) and hypostome (middle mouthpart) with denticles (teeth on venter) in 8 rows (vs. 6 rows for Dermacentor spp.).
Biology of American Dog Ticks
The engorged female drops off the host and seeks a sheltered place to lay her eggs. Over 14-32 days she lays egg masses totaling 4,000-6,500 yellowish-brown eggs, and then dies. Egg hatch usually occurs in 36-57 days. Unfed larvae actively crawl about seeking a host. They can survive for up to 540 days unfed. Larvae require about 4 days (range 3-13 days) to become engorged, then drop off the host and seek shelter for molting purposes. Usually 10+ days (range 6-247 days) are required from drop to nymphal emergence. Unfed nymphs actively crawl about seeking a host. Engorgement usually requires about 6 days (range 3-12) but they can survive for up to 584 days unfed. After feeding, they drop off the host and seek shelter in which to molt. Molting usually requires about 24 days (range 24-291). Adults crawl up on grass or other low vegetation and wait for a host to pass. After both sexes have fed, females are completely engorged in about 10.5 days (range 5-27 days), mating occurs on the host. Males continue to feed but females drop off to lay their eggs. Females require a 3-58 day preoviposition or waiting period before egg laying begins. Unfed adults can survive for about 2-3 years (up to 1,053 days). The entire life cycle (egg to egg) requires from 3 months to more than one year, and both larvae and nymphs can overwinter. In the northern states, a 2-year life cycle may be more common.
In the eastern United States, American dog ticks are the primary vector of Rocky Mountain spotted fever (RMSF) which is caused by the rickettsial bacterium Rickettsia rickettsia. They transmit RMSF from small animals. It is a severe acute infectious disease of the small peripheral blood vessels whose characteristic symptom is a rash that develops in 2-5 days. Mortality in humans is 20% or more. Fortunately, attachment for 2 hours or more is required for transmission.
These ticks also transmit tularemia which is caused by the bacterium Francisella tularensis. It is transmitted from rabbits, meadow mice, ground squirrels, sheep, beavers, coyotes, and various game birds. Symptoms include chills and fever, prostration, an ulcer at the tick-bite site, and tender, swollen lymph nodes.
In addition, American dog ticks can cause tick paralysis which is caused by fluids injected by the tick during feeding, but requires at least 5-6 days of feeding for transmission. If the tick is not removed, death may result from respiratory failure; children are particularly susceptible. If the tick is removed, recovery is rapid and usually within 24-72 hours.
Deticking dogs is an important way that Rocky Mountain spotted fever is spread. Handpicking is dangerous because infected tick secretions on the hands can be transmitted via contact with eyes, mucous membranes, etc.; use forceps for removal.
Habits of American Dog Ticks
The American dog tick does not survive well indoors. If found indoors, it was probably carried in on a dog and dropped off when fully engorged to seek a suitable place for egg laying.
This is a 3-host tick, with each stage requiring a different host. Both larvae and nymphs actively crawl about seeking a small mammalian host, primarily rodents; hosts include the white-footed mouse (Peromyscus), meadow mouse (Microtus), cotton rat (Sigmodon), cottontail and swamp rabbits (Sylvilagus), muskrat (Ondatra), Norway rat (Rattus norvegicus (Berkenhout)), squirrel, and cat. Larvae alone are known from house mouse (Mus musculus (Linnaeus)), jack rabbit (Lepus), and mole (Scalopus aquaticus (Linnaeus)). Only nymphs are known from the wood rat (Neotoma), sheep, cattle, and dog. Because of this kind of host seeking activity, neither larvae nor nymphs are picked up on tick drags.
Adults crawl up grass or other low vegetation, cling to it with their 3rd pair of legs, and wave their other legs about ready to grasp onto any passing host; this is called their “waiting position.” They prefer larger mammals as hosts and these include the preferred dog and others such as man, cattle, opossum, coyote, hog, horse, raccoon, wild cat, squirrel, sheep, skunk, deer, fox, domestic cat, mule, rabbit, Norway rat, donkey/burro, weasel, and woodchuck.
American dog ticks are attracted by the scent of animals and are therefore most numerous along roads, paths, and trails. The concentration is further increased along such travel routes by the dropping of engorged ticks from their host animal.
Larval and nymphal activity usually starts about the end of March, representing those which overwintered, and continues to mid-July. Nymphal activity predominates from June to early September. Adults become active about mid-April, peak in June, and decline until mid-September.
Control of American Dog Ticks
Reducing the likelihood of being fed upon by American dog ticks can be separated into 4 considerations.
- Personal protection. Keep trouser legs tucked into socks or boots, shirts tucked in, and clothes buttoned. Avoid sitting on logs, stumps, or the ground in brushy areas. Periodically inspect clothing and the body for ticks to remove them before they become attached. If a tick is found attached, remove it with a slow steady pull that will not break off the mouthparts and leave them in the skin. It is best to use forceps whose tips are placed on or just behind the mouthparts. If fingers are used, place the fingernails of thumb and index finger on or just behind the mouthparts but be sure to wash thoroughly with soap and water afterwards. Be sure to clean the attachment area. Liberal use of tick repellents is helpful, including application to clothing.
- Habitat modification. Keep the grass cut to 3″ (7.5 cm) or less; this also reduces rodent habitat. Trim back vegetation along trails, paths, and yard edges. Remove debris and ground cover to discourage rodents.
- Removal of hosts. The reduction or elimination of rodents in the area immediately surrounding the house is helpful. This can be done by the use of rodenticides and/or traps.
- Pesticide application. In heavily infested areas the application of an appropriately labeled pesticide may be advisable. Concentrate on the areas most likely to harbor ticks such as along paths, trails, and roads, and the yard-woods interface. The 1st application should be in the early spring to reduce the larvae and nymphs which overwintered.
What does an American Dog Tick look like?
Introduction to the Blacklegged/Deer/Bear Tick
The common name blacklegged refers to their dark legs which are in contrast to the paler body and that of deer because the preferred adult host is the white-tailed deer; in the midwest, it is called the bear tick. Blacklegged ticks are found primarily in the northeastern, mid-Atlantic, southeastern, and northcentral states in the United States, but extend into Mexico. In error, this tick was described in 1979 as the new species Ixodes dammini by Spielman, Clifford, Piesman & Corwin; this error was corrected by Olivier, Jr., et. al. in 1993.
Powassan encephalitis is caused by Powassan virus. It occurs primarily in the Great Lakes region and the northeastern states. Borrelia miyamotoi is an infection causing illness, with a distribution similar to that of Lyme disease.
This tick is of medical importance because it is an important vector of Lyme disease, anaplasmosis, human babesiosis, Powassan encephalitis, etc. In 2014, the CDC reported that about 30,000 Americans are reported with Lyme disease every year.
Recognition of the Blacklegged/Deer/Bear Tick
Unengorged female about 1/8″ (2.7 mm) long, male smaller (about 1/16″/2 mm). Body oval, dorsoventrally flattened (top to bottom), not hard-shelled. Color orangish brown except legs, mouthparts and scutum (dorsal shield just behind mouthparts) dark reddish brown but abdomen darker when engorged; male body reddish brown overall. Scutum present, longer than wide, almost completely covering dorsum in male. Eyes lacking. Capitulum (mouthparts and their base) visible from above; hypostome (toothed median mouthpart) with apex sharply pointed. Coxa I (1st pair of legs) with internal spur (projection from coxal base) overlapping coxa II (2nd pair of legs). Abdomen with anal groove in front of anus; lacking abdominal festoons (rectangular areas divided by grooves along posterior margin).
Unengorged 1st instar larvae about 1/32″ (0.7-0.8 mm) long, with 6 legs; 2nd instar nymphs about 1/16″ (1.1-1.8 mm) long, with 8 legs.
Similar Groups to the Blacklegged/Deer/Bear Tick
(1) Pacific/western blacklegged tick (Ixodes pacificus) with scutum (dorsal shield) almost round (subcircular);
(2) Other ixodid ticks (non-lxoctes) with anal groove either behind anus, indistinct, or absent, festoons often present;
(3) Soft ticks (Argasidae) lack a scutum (dorsal shield), with capitulum (mouthparts and their base) ventral, not visible from above.
Biology of the Blacklegged/Deer/Bear Tick
Although the life cycle (egg to egg) can be completed in 2 years in nature, it may be extended to 4 years if hosts are scarce. Adult ticks feed during the winter primarily on the white-tailed deer, Odocoileus virginianus (Zimmermann). Here they mate, with the male dying shortly after mating and the female remaining on the host. In the spring, the female drops off the host and deposits about 3,000 eggs. The 6-legged larvae hatch out in several weeks (48-135 days) and can be found June through September. They feed for 3-9 days but only once, usually on small mammals such as mice, chipmunks, voles, etc. but the preferred larval host is the white-footed mouse, Peromyscus leucopus Rafinesque. Larvae feeding before September molt promptly and overwinter as 8-legged nymphs; those which feed later, overwinter engorged and molt into nymphs the following spring. Nymphs feed for 3-8 days but only once during the summer, usually on mice or larger mammals such as squirrels, raccoons, opossums, skunks, dogs, and humans, or on birds. Nymphs can be found from April through August, with the population usually peaking in June or July. These fed nymphs then require 25-56 days to molt into adults in the autumn. The adults attach primarily to the white-tailed deer, engorge, and mate. The male dies after mating but the female continues to feed until egg development is completed and remains on the deer until spring when she drops off to lay eggs. Shortly after her eggs are laid, the female dies.
If adults do not feed during their first season (autumn through spring), they die before summer’s end. If nymphs do not feed their first season (summer), most die off but they can survive through 2 seasons (May through August of the next year); they develop into adults in the same year in which they feed. Unfed larvae survive less than one year, they usually survive the winter but die during the following year.
Lyme disease is caused by the spirochete, Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner, which is a corkscrew-shaped bacteria. Its primary wild reservoir is the white-footed mouse which is infected by the spring-feeding, pathogen-infected blacklegged/deer tick nymphs. These white-footed mice then serve to infest the later-feeding blacklegged/deer tick larvae, which keeps the disease cycle going. Tick eggs don’t contain the spirochete, so it is acquired via feeding.
It is the pathogen-infected blacklegged/deer tick nymphs, which are most active in mid-summer (May-July) and use a wide variety of hosts, that are primarily responsible for Lyme disease in humans in the northeast and midwest. Larvae and nymphs have been collected on 29 species of mammals in 7 orders, and from 49 species of birds (23 species being migratory birds) in 17 different families.
In the west, the primary Lyme disease vector is the Pacific/western blacklegged tick, Ixodes pacificus Cooley and Kohls. In the south, the vector(s) of a Lyme-like disease (caused by Borrelia lonestari) is suspected to be the lone star tick, Amblyomma americanum (Linnaeus), but it is questionable if it is the primary vector.
Anaplasmosis and ehrlichiosis are caused by rickettsiae that primarily infect circulating leukocytes. Anaplasma [formerly Ehrlichia] phagocytophilum is the causative agent of human granulocytic anaplasmosis (HGA; formerly HGE) and infects granulocytes. It occurs mostly in the upper midwest and northeastern United States. Symptoms include fever, chills, headache, muscle aches, nausea, and vomiting.
Human babesiois is a tick-borne disease caused by two protozoa in the family Piroplasmordia: Babesia microti (a rodent parasite) and Babesia divergens (a cattle para- site). In the United States, it is B. microti that is vectored by the blacklegged tick. In Europe, it is B. divergens that causes the problem. Symptoms are very similar to those of malaria. The concern here is that the disease can be fatal in 5% of cases and that it can be trans- mitted via blood transfusions (more than 30 documented cases; likely under-reported because it often goes unrecognized and unreported).
Habits of the Blacklegged/Deer/Bear Tick
Blacklegged/deer ticks climb grass and shrubs to wait for a passing host, and move very little laterally. They concentrate on such vegetation located in transitional areas/zones such as where forest meets field, mowed lawn meets unmowed fence line, a foot/animal trail through high grass or forest, etc. Because these transitional areas or edge habitats are where most animals travel sometime each 24-hour period, this is where the ticks are mostly likely to acquire a host.
The other habitat most likely to harbor ticks is the den, nest, or nesting area of its host such as that of skunks, raccoons, opossums, but especially the white-footed mouse. The white-footed mouse prefers woody or brushy areas. It nests in any place that gives shelter such as below ground, in stumps, logs, old bird or squirrel nests, woodpiles, buildings, etc.
A favorite feeding area for these ticks on humans is at the back of the neck, at the base of the skull; long hair makes detection more difficult. However, the ticks will usually crawl about for up to 4 hours or so before they attach. Then, a tick has to be attached for a period of 6-8 hours before a successful transmission can take place.
Control of the Blacklegged/Deer/Bear Tick
The reduction of these ticks is a 5-step process. The first 2 are sanitation and personal protection, which are the responsibility of the homeowner or occupant(s) but usually require education by the PMP.
- Sanitation, consists of the following: (a) keep grass cut low including around fence lines, sheds, trees, shrubs, swing sets and other difficult to cut locations; (b) remove weeds, woodpiles, and other debris which are attractive to mice as nesting areas, and leaf litter which is attractive to ticks, especially the nymphs; (c) keep garbage can lids on tightly to discourage opossums, raccoons, and skunks from coming into the yard to raid garbage cans for food because these animals all harbor the ticks which transmit the Lyme disease pathogen; (d) discourage feeding birds because the seeds attract deer mice, the major reservoir host for the Lyme disease pathogen; and (e) install a chimney screen to keep squirrels, raccoons, and birds away.
- Personal protection, consists of: (a) use deet or permethrin containing repellent and tuck pants into socks or boots when going into suspect areas; (b) check children for ticks when they come into the house because it takes up to 4 hours, possibly longer, for the tick to start feeding; (c) wear light colored clothing which makes spotting ticks easier; (d) pets which go outdoors may increase the chance of the occupant’s encounter with these ticks, especially cats; and (e) encourage the vet to check any pet’s blood to determine if they are carrying the Lyme disease spirochete.
- Inspection, is done by performing a tick drag on a routine basis in areas where the ticks have been reported or for homes adjacent to heavily wooded or uninhabited areas. The drag consists of light colored heavy-duty cloth, 7 feet long by 2 feet wide, which is securely weighted at both ends. A rope is attached to one end and this drag is walked around the suspect property.
- Treat the perimeter of the property or the entire property with an appropriately labeled pesticide if ticks show up on the drag. Wettable powder and microencapsulated formulations work best.
- Do an exterior perimeter rodent control program using PVC pipe with a glue board placed inside.
What does a Blacklegged/Deer/Bear Tick look like?
Lyme Disease
The symptoms are usually divided into 3 stages, and they mimic several different commonly occurring diseases.
Symptoms: Spreading rash, fever, flu-like symptoms, aches.
Stage 1: Expanding rash (Erythema migrans or EM rashes). 3-30 days after bite.
- Ringlike/bullseyelike appearance to rash.
- One or more rash sites.
- May or may not have flu symptoms.
- May come and go or persist.
Stage 2: Complications or disorders of the heart or nervous system.
- Heart. Varying degrees of blockage of the heart muscle.
- Nervous system. Meningitis, encephalitis, facial paralysis.
- “Bell’s palsy,” other conditions involving peripheral nerves.
- Migratory pain in joints, tendons, muscles, and bones, often without joint swelling or redness.
Stage 3: Months to years after disease onset.
- Arthritis that appears and disappears intermittently for several years.
- Enlarged knee joints.
- Erosion of cartilage and bone.
Treatment notes:
- Once bitten by a blacklegged/deer tick possessing the spirochete, it may not produce antibodies in the victim for up to 6 weeks. Therefore, it takes time to verify that one has Lyme disease.
- Oral medications for Lyme disease can destroy the spirochetes in the blood and give an antibody reading that the person is “cured.” However, the spirochete may persist in the brain and reappear in the person 5-10 years later. Therefore, intravenous treatment is advised over oral medications by some physicians considered experts in this area, especially for persons showing Stage 2 and Stage 3 symptoms.
Tick Removal:
- The best way to remove a tick found attached to a person or pet is to firmly grasp it with a pair of tweezers as close to the skin as possible.
- Pull firmly but gently backwards until the tick pulls free.
- Do not touch the tick, but save it in rubbing alcohol for later identification.
Epidemiological Notes:
- Epidemiologists have isolated an unidentified type of spirochete from ticks collected in southeastern Missouri which appears to be different from Borrelia burgdorferi.
- Initial studies show that infection by this “new/different” spirochete can result in the expanding rash (EM) but that it is less often followed by multiple skin lesions than with Lyme disease.
- Therefore, more than one species of tick may be the vector. It is best to characterize the Missouri victims as suffering from a “Lyme-like” illness rather than Lyme disease.
Introduction to Brown Dog Ticks
This tick gets its common name from its overall reddish brown color and that it is common on dogs. Although the brown dog tick is the species most commonly encountered indoors, it rarely attacks man. However, it can serve as a vector of Rocky Mountain spotted fever (RMSF) and Boutonneuse fever. This tick is found throughout the United States and the world.
Recognition of Brown Dog Ticks
Unengorged adults are about 1/8″ (3 mm) long, but enlarge up to about 1/2″ (12 mm) long when engorged with blood. Body flattened dorsoventrally (top to bottom). Reddish brown in color, but when engorged, engorged parts of body change to gray-blue or olive color. Male with tiny pits scattered over the back. Scutum (dorsal shield just behind mouthparts) present which covers male’s entire back but only front part of female’s back. Eyes on margin of scutum. Capitulum (mouthparts and their base) visible from above; basis capituli (base for mouthparts) laterally produced/angular, not straight; 2nd segment of palpi about as long as wide. Abdominal festoons (rectangular areas divided by grooves along posterior margin) present; anal groove present, posterior to anus.
Similar Groups to Brown Dog Ticks
(1) American dog tick (Dermacentor variabilis) and other Dermacentor species have sides of basis capituli (base for mouthparts) straight, not laterally produced/angular, although base may be angular laterally, and abdomen with 11 festoons (rectangular areas divided by grooves) along posterior margins.
(2) Lone star tick (Amblyomma americanum) has 2nd segment of palpi twice as long as wide, female with pale markings near hind end of scutum (dorsal shield).
(3) Cattle tick (Boophilus annulatus) lacks anal groove and festoons.
(4) Bird and rabbit ticks (Haemaphysalis spp.) lack eyes, anal groove behind anus, festoons present, 2nd segment of palpi laterally produced.
(5) Ixodes spp. lack eyes, have anal groove in front of anus, lack festoons.
(6) Soft ticks (Argas, Ornithodoros, etc.) lack a scutum (dorsal shield), capitulum (mouthparts and their base) ventral, not visible from above.
Biology of Brown Dog Ticks
The engorged female drops off the host dog and seeks a sheltered spot in which to lay her mass of typically 1,000-3,000 tiny, dark brown eggs. Since she has a tendency to crawl upwards, eggs are often deposited in cracks and crevices near wall hangings, ceiling, or roofs. She dies afterwards and the eggs hatch in 19-60 days into minute, 6-legged larvae or seed ticks. They crawl down the walls and attach to a dog as soon as possible but can survive for 8 months without food or water. After engorging for 3-6 days, during which they become globular, blue, and about 1/16″ (2 mm) in diameter, they drop off and seek a sheltered place in which to molt. In 6-23 days they become 8-legged, reddish brown nymphs, which can survive for about 3 months without food or water. They again attach and engorge for 4-9 days, becoming oval, about 1/8″ (3 mm) wide, and dark gray. The nymphs then drop off, hide, and usually molt in 12-19 days into adults. Although the adults attach to a dog at the first opportunity, they can survive 18 months before attachment. Once attached, they engorge for 6-50 days, mate, and the females drop off to lay eggs and repeat the cycle. Under favorable conditions, the cycle can be completed in about 2 months but there are usually only 2 generations per year in the north and 4 in the south.
Although dogs are the preferred host, they will feed on other mammals (including domestic animals and humans) if dogs are not available. They rarely attack humans, but brown dog ticks can serve as vectors of Rocky Mountain spotted fever (RMSF) which is caused by the rickettsial bacterium Rickettsia rickettsii, and Boutonneuse fever which is caused by the rickettsial bacterium Rickettsia conorii.
Habits of Brown Dog Ticks
The brown dog tick does not do well outdoors in the woods in the United States. They prefer warm, dry conditions where dogs live. They do not travel far after engorgement and dropping off the host. They typically move upward, a behavior that usually promotes host encounters. Brown dog ticks may attach themselves anywhere on a dog. The adults typically attach on the ears and between the toes, but the larvae (seed ticks) and nymphs typically attach on the back.
Brown dog ticks are unusual among ticks in that they can complete their entire life cycle indoors. This indoor habit means that they can and have established populations in colder climates.
Control of Brown Dog Ticks
Tick control is a 4-step process.
- Sanitation. The homeowner/occupant of the infested home and/or the owner/user of the infested kennel must thoroughly clean the home and/or kennel and remove all debris to remove/eliminate as many ticks as possible and facilitate pesticide application. Pet bedding and resting areas should receive careful attention.
- The dog/pet must be treated, preferably by a veterinarian or grooming parlor, on the same day of treatment, either before or while the premises are being treated.
- Indoor treatment by the pest management professional. Using an appropriately labeled pesticide as per label instructions, thoroughness will be the key to success. Apply the pesticide to areas frequented by the dog, paying particular attention to sleeping quarters and any resting places where ticks have probably dropped off. If the dog rests on overstuffed furniture, remove the cushions and treat the cracks and crevices. Because ticks hide in secluded places to molt, other critical areas include cracks and crevices around baseboards, door frames, window frames, floor and wall crevices, around wall molding and hangings, and under the edge of carpets. If the dog can get under porches or into crawl spaces, ticks may hide in the subflooring where liquids are difficult to apply, so dusts or aerosols are recommended.
- Outdoor treatment by the pest management professional. Treatment should be made to grassy and bushy areas adjacent to the home and/or kennel, the roadside, the edges of lawns and gardens, and along any footpaths/walks, as well as to any dog resting areas. Remember that ticks do not travel far from where they drop off their host. Wettable powder and microencapsulated formulations are particularly effective.
What does a Brown Dog Tick look like?
Introduction to Silverfish
All members of the order Zygentoma have a teardrop/carrot/fish-shaped body and get the common name of bristletail because of their 3 long, bristle-like or tail-like appendages on the posterior/rear end of their body. Firebrat is the common name for those species which prefer areas of high temperature, 90°F (32.2°C) and above. Firebrats are found throughout the United States, and the world.
Recognition of Silverfish
Adult body length, not including tails, about 1/2-3/4″ (12-19 mm). Wingless with flattened body. Shape teardrop/carrot/fishlike, tapering from head to rear, and generally covered with scales. Color silvery to gun metal, 1 species with dark lines running length of body. Antenna long, threadlike. Posterior end of abdomen with 3 long, bristlelike appendages (2 cerci, 1 median caudal filament). In addition, compound eyes small, widely separated; ocelli absent; coxae lack styli (fingerlike processes); tarsi 3- or 4-segmented; some abdominal segments with a pair of styli; abdominal sternites (underside of segment) lack median setal combs (tufts of hair) or if present, last abdominal tergite (upper side of segment) longer than wide; abdominal tergites with outer dorsal setal combs (tufts of hair) or if lacking, last abdominal tergite longer than wide.
Immatures similar to adults in appearance, except for size. Scales appear with 3rd or 4th molt.
Similar Groups to the Silverfish
(1) Firebrats (order Zygentoma) lack silvery sheen, usually with mottled color, abdominal sternites (underside of segment) with median setal combs (tufts of hair) and last abdominal tergite (upper side of segment) wider than long.
(2) Jumping bristletails (order Microcoryphia) have large compound eyes which touch each other, middle, hind coxae usually bear styli (fingerlike processes), jump when disturbed.
(3) Diplurans (order Diplura) have only 2 appendages (cerci) at end of abdomen, body without scales, lack compound eyes, tarsi 1-segmented.
(4) Springtails (order Collembola) lack 3 abdominal appendages/tails but usually have a forked appendage at end of abdomen, lack styli on abdomen, antenna short.
(5) Larvae and wingless adults of insects with complete metamorphosis lack 3 bristlelike/taillike appendages on abdomen and styli on abdominal segments.
Damage and Signs of Infestation of Silverfish
Feeding marks are irregular whether they are holes, notches along an edge, or surface etchings. Yellow stains, scales, and/or feces (tiny black pepper-like pellets) may be seen on infested materials.
Representative Species of Silverfish
- Silverfish, Lepisma saccharina Linnaeus. Uniformly silver to steel gray to almost black, with metallic sheen; abdomen without setal combs (tufts of hair) on top but with median setal combs present on abdominal underside; adult body length excluding tails 1/2″ (12-13 mm); throughout the United States.
- Fourlined Silverfish, Ctenolepisma lineata (Fabricius). Scales dark gray with 4 dark lines running length of body; abdomen lacking median setal combs (tufts of hair) beneath but with setal combs above; with 3 pairs of styli (fingerlike processes) on rear of abdomen; adult body length excluding tails about 5/8″ (16 mm); eastern United States, southern California, Arizona, Nevada and Oregon.
- Gray Silverfish, Ctenolepisma longicaudata Escherich. Scales uniformly gray; abdomen lacking median setal combs (tufts of hair) beneath but with setal combs above; with 2 pairs of styli (fingerlike processes) on rear of abdomen; adult body length excluding tails about 3/4″ (19 mm); midwest, south, and southern California.
Biology of Silverfish
The silverfish (L. saccharina) female lays about 1-3 eggs per day, placing them in cracks, under objects, or left exposed. Egg hatch requires 72-90°F (22-32°C) and at least 50-75% relative humidity. Developmental time (egg to adult) is 3-4 months under favorable conditions, but may require up to 2-3 years otherwise. The majority live about 3 years. The most favorable conditions are 72-80°F (22-27°C) and 75-97% RH.
The fourlined silverfish (C. lineata) produces the enzyme cellulase in its midgut and can therefore digest cellulose.
The gray silverfish (C. longicaudata) female lays her eggs in batches of 2-20, placing them in cracks. The first instar lacks setae (hairs) and scales, scales appear in the 4th instar, and genitalia in the 14th instar. Sexual maturity is reached in 2-3 years and it may molt 3-5 times per year for another 5 years. Cellulose-digesting bacteria and enzymes are found in its midgut.
Habits of Silverfish
All these silverfish species hide during the day and prefer to hide or rest in tight cracks or crevices. They can be found almost anywhere in a house including living rooms, bedrooms, bathrooms, attics, basements, garages, and shake roofs. Silverfish infest commercial structures such as offices, stores, and libraries. They tend to roam quite some distance while searching for food, but once they find a satisfactory food source, they remain close to it. Within structures, they can be breeding in a variety of areas, including wall voids, in/under the subflooring, attics, etc. Silverfish can survive for weeks without food or water.
Many species of silverfish are good climbers. Shake roofs are excellent breeding sites for silverfish during the warm weather months. Here, there is an abundance of moisture, cellulose, starch, and dead insects. From here, they can easily gain entrance and move down through the insulation to the sheetrock board with its glue and paper coating below. People notice them when they come down on ceiling soffits and/or drop from skylights and canister light fixtures in the ceiling.
Silverfish (L. saccharina) prefer areas of room temperature (70-85°F/21-29°C) and high relative humidity (70-100%). They prefer proteins to carbohydrates and are cannibalistic. Silverfish are often introduced into buildings via cardboard cartons of books and papers from an infested location. They are pests of paper, particularly of glazed paper and paper with sizing, wallpaper and wallpaper paste, book bindings, gummed labels and envelopes, etc. Silverfish eat proteins such as dried beef and dead or injured of their kind.
The fourlined silverfish is not so limited by temperature and moisture. It may be found throughout a building, in the basement, in wall voids, the attic especially if the roof has wooden shingles, and in the garage. Outdoors, it occurs in the mulch of foundation flower and shrubbery beds, and under the bark of Eucalyptus trees in California.
The gray silverfish can be found throughout a building from basement to attic, but are not found outdoors. Often heat ducts and ventilators from the basement serve as avenues for widespread infestation. They survive well in both dry and moist conditions. Gray silverfish feed on carbohydrates and proteins of both plant and animal origin. They are fond of wheat flour and beef extract, especially when used as a paste on paper. Gray silverfish prefer papers of high chemical pulp content such as onion skin, cleansing tissue, cellophane (almost pure cellulose), etc., as opposed to newsprint, cardboard, and brown wrapping paper. They readily eat artificial silk, linen, rayon, lisle (long-strand cotton), and cotton, but not wools or true/natural silks; linen is most preferred.
Control of Silverfish
The key to control is identification which directs one to the preferred areas of habitation and food materials as outlined above. Identification is followed by a thorough inspection of preferred habitat areas and where appropriate food materials are present. If the infestation is localized on the inside, one can assume that it is recent and was either brought in via infested items or represents a recent invasion from the outside. Once the infestation(s) is found, selection of an appropriate pesticide and formulation is followed by a thorough application. Many infestations are very localized and environmental modification can greatly enhance control-e.g. controlling or eliminating moisture by repairing leaking pipes, sealing up easily accessible cracks and crevices, removal of potential food sources, etc. Dusts, especially inorganics, are particularly effective in wall voids, attics, crawl spaces, bathroom and kitchen fixture voids, subflooring voids, etc.
If the infestation is widespread, then attention should be directed to the outside. Silverfish can be found in firewood, wood piles, under debris piled up on the soil, in/under plywood and cardboard, etc. Anything stored against or very near the house’s exterior must be moved or removed since silverfish can easily climb up walls and find entrance around window and door frames, utility pipes, vents, fascia boards, etc. The cleared building perimeter can then be treated with an appropriately labeled pesticide. Be sure to treat up under the bottom row of any siding present.
If the shake roof is found to be infested, advise the customer to have it professionally and thoroughly powerwashed, and then water sealed; it should be resealed every other year. If the shakes are in poor condition and/or the customer cannot or will not have the shakes cleaned and sealed, then all of the crevices associated with the overlapping shakes and flashing will require thorough pesticide application, a very laborious process. If the infestation goes into the attic space, it may be necessary to pull back the insulation, treat underneath it with a long-lasting dust, and then put it back in place; perimeter areas including the roof overhang and wall studs below are critical and cannot be neglected.
Treatment for control of the fourlined silverfish will probably require treatment of foundation mulch beds and possibly the underside of shingles. Bookshelf treatment involves a thorough crack and crevice treatment of the bookcase itself, not treatment of the books. ULV treatment of heavily infested rooms is helpful in reducing numbers as is the use of a vacuum.
What do Silverfish look like?
Introduction to Earwigs
The common name of “earwig” comes from an old European superstition that these insects enter the ears of sleeping people and bore into the brain. This belief is without foundation. The forcepslike cerci are apparently used as both offensive and defensive weapons, and are sometimes used to capture prey. Earwigs are worldwide in distribution, with about 22 species occurring in the United States.
Recognition of Earwigs
Adults about 1/4-1″ (5-25 mm) long, with body elongate, flattened in form. Color varies from pale brown with dark markings to uniformly reddish brown to black, but with paler legs. With 4 wings (rarely wingless), front wings leathery, short, and meeting in a straight line down the back whereas, hind wings membranous, fan-shaped, and folded under front wings. Cerci well developed and forcepslike but usually differ in shape in the sexes. Antenna threadlike, about half body length. Tarsi 3-segmented. Mouthparts chewing.
Nymphs similar to adults but have no wings.
Similar Groups to Earwigs
(1) Rove beetles (Coleoptera; Staphylinidae) and other beetles with short elytra (wing covers) lack forcepslike cerci.
(2) Cockroaches (order Blattodea) have short feelerlike cerci, 5-segmented tarsi.
Representative Species of Earwigs
- The European earwig (Forficula auricularia Linnaeus, family Forficulidae) is the most common pest species. Adults are about 5/8″ (16 mm) long including forceps. Some males are considerably larger with forcepslike cerci of about 1/4″ (5 mm) while other males have forceps of about 3/8″ (9.5 mm) long. They are dark reddish brown with reddish head and paler wing covers, legs, and antennae. Antennae 12-segmented. The 2nd tarsal segment is broadly lobed, prolonged beneath the 3rd segment.
- The red-legged earwig (Emborellia annulipes (Lucas), family Carcinophoridae) is a native American species which is common in the south and southwest. It is a wingless species. Adults are usually about 1/2-5/8″ (12-15 mm) long but may reach about 1″ (25 mm). They are dark brown to black with a yellowish brown undersurface. The yellowish legs have femora and tibiae ringed with brown stripes. The antennae are about 16- segmented and black, but the 3rd, 4th and usually the 5th segments from the apex are yellow to white. The 2nd tarsal segment is cylindrical. The male’s forcepslike cerci are distinctly asymetrical, the right member much more strongly curved than the left.
- The striped earwig (Labidura riparia (Pallas), family Labiduridae), also called the shore or riparian earwig, is a second species common in the southern and southwestern states. Adults are about 3/4-1″ (20-25 mm) long. The color varies from pale brown with indistinct darker markings to chestnut or reddish brown with indistinct paler or darker markings to black. The abdomen is usually banded and the cerci are usually darker at the tips. The 2nd tarsal segment is cylindrical. The male’s forcepslike cerci are symmetrical, usually long and distinctly toothed while others are shorter and weakly toothed.
Biology of Earwigs
Earwigs typically overwinter outdoors as adults in protected situations. The European earwig overwinters in pairs in earthen cells 1 1/8-1 1/2″ (30-40 mm) beneath the surface and the striped earwig in subterranean burrows or chambers. The females lay and tend their eggs in these underground situations and then tend the newly hatched nymphs. Earwigs have 4-5 nymphal instars. Nymphal development averages about 56 days (range 40-60) for the striped and takes about 68 days for the European earwig, both having 4 instars. European females lay about 30-55 eggs the first batch and many fewer the second time. The striped female lays about 50 eggs the first time and may lay 3-4 more batches. The red-legged female lays about 40-53 eggs on the average and its 5 nymphal instars require about 80 days to complete development. Some females may live as long as 7 months after attaining maturity.
Earwigs have a distinctive disagreeable/repugnant odor that is released when they are crushed, but some species can squirt such a liquid. They are gregarious in nature, typically occurring in groups. Red-legged earwigs have been reported to cause minor skin abrasions in humans.
Habits of Earwigs
Earwigs are nocturnal or active at night and hide during the day in moist, shady places such as under stones or logs, or in mulch. Neither the eggs nor nymphs can withstand long periods of dryness.
Earwigs feed on live or dead plants and/or insects. At times they damage cultivated plants. The European earwig occasionally damages vegetables, flowers, fruits, ornamental shrubs, and trees, and has been recorded as feeding on honey in beehives. The red-legged earwig has been recorded as a pest of Irish and sweet potatoes in storage, damaging the roots of greenhouse vegetables, and as a pest in flour mills, breweries, meat-packing plants, slaughter houses, gardens, and nurseries. The striped earwig has not been recorded as damaging plants.
European earwigs are very good climbers and can either go up outside walls or follow tree branches in contact with structures onto structures. The dark, damp habitat afforded by weathered shake roofs is very attractive to them and from here they can enter struc- tures through cracks and penetrations.
Earwigs are attracted to lights or to insects attracted to lights. Usually it is the European and red-legged earwigs which occasionally invade homes, sometimes by the hundreds or thousands.
Control of Earwigs
The key to control is the removal of unessential mulch, plant debris, and objects such as stones and boards from around the structure. The purpose of this is to establish a low-moisture zone that is disagreeable to earwigs. Microencapsulated and wettable powder residual formulations applied as 3-10 foot (1-3 m) band treatments are particularly effective, but be sure to treat underneath the bottom of any siding present. Baits are very effective.
If the shake roof is found to be infested, advise the customer to have it professionally and thoroughly powerwashed, and then water sealed; it should be resealed every other year. If the shakes are in poor condition and/or the customer cannot or will not have the shakes cleaned and sealed, then all of the crevices associated with the overlapping shakes and flashing will require thorough pesticide application, a very laborious process.
Indoor control is supplemental to the outdoor control measures.
What do Earwigs look like?
Introduction to Centipedes
Centipedes are sometimes called “hundred-leggers” because of their many pairs of legs. Even though centipedes are predaceous and therefore beneficial, most customers consider them a nuisance pest. Some species can inflict a painful bite, but it is not lethal. They are widely distributed throughout most of the United States and the world.
Recognition of Centipedes
Adults about 1/8-6″ (4-152 mm) long, elongate, flattened, and wormlike. Color usually yellowish to dark brown, sometimes with darker stripes or markings. With 1 pair antennae, 14-50-segmented. Some with compound eyes, most with a cluster of simple eyes (ocelli) on each side of head or no eyes. Most body segments bear 1 pair of similar legs, except 1st pair behind head modified into claw/like poison jaws and last 2 pairs directed backward and often different in form. Pairs of legs number 15-177, with 1 pair per segment.
First instar centipedes usually have 4 pairs of legs. Additional segments and pairs of legs are added with additional molts.
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Similar Groups to Centipedes
(1) Millipedes (class Diplopoda) with slightly flattened body have most body segments with 2 pairs of short legs, antennae short, usually 7-segmented.
(2) Pillbugs and sowbugs (order Isopoda) with 7 pairs of legs.
Representative Species of Centipedes
- The usual pest species is the common house centipede Scutigera coleoptrata (Linnaeus) which is about 1-1 1/2″ (25-38 mm) long. Its body is grayish yellow with 3 dorsal longitudinal dark stripes. The antennae and last pair of legs are longer than its body. It has 15 pairs of long legs. The first instar has 4 pairs of legs and more legs are added through the next 5 larval molts (5, 7, 9, 11, and 13 pairs respectively). Then there are 4 additional pre-adult/post-larval instars before adulthood, each with 15 pairs of legs.
- Our largest centipedes are in the genus Scolopendra and may be as much as 6″/15 cm long. In the southern states, S. heros Girard and S. moritans (Linnaeus) are the larger common species and in the southwestern states, it is S. polymorpha Wood. Their legs and antennae are much shorter than those of the house centipede.
Biology of Centipedes
Centipedes typically overwinter outdoors in protected situations and lay their eggs, usually in or on the soil, during the summer. Females of Scutigera have been observed to produce 35 eggs over a period of days. The common Scutigera may live for more than a year, other species live as long as 5-6 years.
All centipedes have poison jaws with which they inject venom to kill their prey. If handled roughly, some of the larger species can break the human skin, resulting in a bite which causes some pain and swelling, something like a bee sting. However, the large Scolopendra can inflict a very painful bite and should be handled with great care.
Habits of Centipedes
Centipedes are typically found in areas of high moisture such as loose bark, in rotting logs, under stones, trash, piles of leaves and grass clippings, flower-bed mulch, etc., where their typical prey is found. Most centipedes are nocturnal or active at night.
They occasionally invade structures, especially S. coleoptrata, where they survive on flies, spiders, etc. Although they may be found anywhere in a house, the usual places are damp basements, bathrooms, damp closets, and potted plants.
Centipedes are primarily carnivorous and obtain most of their moisture needs from their prey. Some species will sometimes feed on plant tissues, causing injury.
Control of Centipedes
The key to centipede control is to reduce or eliminate moist areas and harborage. For example, remove accumulations of leaves and grass clippings, logs, stones and rocks, store firewood, etc. up off the ground, provide adequate ventilation in crawl spaces, etc. Indoors, centipedes are easily removed with a vacuum.
Application of appropriately labeled residuals can be made to building foundation walls, perimeter flower and/or ornamental plant beds, unfinished basements, and crawl spaces. Wettable powder and microencapsulated formulations are best. Control of the small arthropods upon which centipedes feed helps make building areas less attractive to them.
What do Centipedes look like?
Introduction to Millipedes
Millipedes are sometimes called “thousand-leggers,” but they usually have 30-90+ pairs of legs. The leggiest adult is Illacme plenipes, with males typically having 201 pairs and females 333 pairs; record is 375 pairs. Millipedes are widely distributed throughout the United States and most of the world, with about 1,000 species occurring in the U.S.
Recognition of Millipedes
Adults about 1/16-4 1/2″ (2-115 mm) long, usually cylindrical and wormlike but some slightly flattened. Color usually blackish or brownish but some red, orange, or with mottled patterns. With 1 pair short, 7-segmented antennae. Usually a cluster of simple eyes (ocelli) on each side of head. Most body segments bear 2 pairs of legs, except first 3-4 segments and last 1-3 segments which have 1 pair or no legs.
First instar millipedes usually have no more than 7 body segments and 3 pairs of legs. Additional segments and pairs of legs are added with each molt.
Similar Groups to Millipedes
(1) Centipedes (class Chilopoda) with flattened body, have 1 pair of legs per body segment, antennae with 14 or more segments.
(2) Pillbugs and sowbugs (order Isopoda) with 7 pairs of legs.
Biology of Millipedes
Millipedes overwinter as adults or young. Adult females lay 20-300 eggs, either in soil cavities or among decaying organic matter during the summer; however, they can breed year round under tropical conditions. Eggs hatch after several weeks. In most species, there are from 7-10 molts. In many species sexual maturity is not reached until the second year, others require 4-5 years. They eat their molted skins to restore lost supplies of calcium. Adults often live for several years.
Members of several millipede groups give off an ill-smelling, repugnant fluid through openings along the sides of the body. In some species, this fluid contains hydrocyanic acid, iodine, and quinone which is toxic to some arthropods and small animals. It can cause vesicular dermatitis (small blisters) in humans.
Habits of Millipedes
Millipedes have high moisture needs, like pillbugs and sowbugs. They are typically found in areas of high moisture and decaying vegetation such as under trash, piles of grass clippings, flower-bed mulches, leaf litter, etc. Millipedes are nocturnal or active at night. Sometimes, and usually in the autumn, millipedes will migrate in great numbers. This is thought to be the result of natural hibernation movement, heavy rains and a rising water table forcing them out of their natural abodes, warm temperatures in late autumn, their apparent habit of crawling up such things as trees and walls for mating purposes, and/or extremely high populations building up under very favorable conditions, followed by drought. This can involve several hundred individuals to hundreds of thousands, sometimes several million millipedes. They usually do not survive indoors for more than a few days unless there are high moisture conditions and a food supply present.
Millipedes are primarily scavengers and feed on decaying organic matter, usually plant material but occasionally on dead insects, earthworms, and snails. They may attack living plants during dry periods in order to obtain needed moisture.
Control of Millipedes
The key to controlling millipedes is to reduce or eliminate the moist areas which make their survival possible. Outdoors, 4 things should be done.
(1) Dethatch the lawn because dense thatch just above the soil surface holds moisture.
(2) Mow the lawn closely and edge it because this promotes quicker drying.
(3) Remove debris such as accumulations of leaves and wood debris, rocks, heavy mulch, store firewood, etc. up off the ground, and provide adequate ventilation in crawl spaces to reduce sheltered, damp hiding places.
(4) Water lawns in the early morning to allow the grass to dry during the day. Application of appropriately labeled residuals can be made to building foundation walls, perimeter flower and/or ornamental plant beds, unfinished basements, and crawl spaces. Wettable powder and microencapsulated formulations are best, but dusts are also good in drier crawl spaces.
During mass migrations, residual pesticide deposits will have little effect because of the short exposure time to them. If the major population can be found (may require a night-time inspection), such as in outlying grassy or wooded areas, these should be treated during the day with an appropriately labeled contact insecticide. Otherwise, night-time treatment of the millipedes with an appropriately labeled contact pesticide may be required for several nights. Removal with a shop-vac works well and may be the only acceptable solution. Indoors, they are most easily removed with a vacuum.
What do Millipedes look like?
Introduction to Pillbugs (Rollie Pollies)
Pillbugs are sometimes called “roly-polies” and get this common name because they roll up into a tight ball when disturbed. These land-dwelling crustaceans are arthropods but not insects. They are worldwide in distribution. In the United States, the most common species is Armadillidium vulgare (Latreille) which is in the family Armadillidiidae; it has worldwide distribution.
Recognition of Pillbugs (Rollie Pollies)
Adults about 1/4-5/8″ (7-15 mm) long, convex above but flat or hollow beneath. Color slate gray. Typical of crustaceans, pillbugs with 7 pairs of similar legs (1st 2 instars with only 6 pairs); 2 pairs of antennae, 1 tiny, the other readily visible; body dorsoventrally flattened (top to bottom). Capable of rolling up into a tight ball. Uropoda (paired terminal appendages attached on posterior or rear end) short and rounded, usu- ally not visible from above.
Similar Groups to Pillbugs (Rollie Pollies)
(1) Sowbugs (order Isopoda) with 2 prominent taillike appendages (uropoda) which protrude out from rear of body, visible from above.
(2) Centipedes (class Chilopoda) with 15 or more pairs of legs.
Biology of Pillbugs (Rollie Pollies)
The eggs are deposited and hatch within the brood pouch or marsupium on the underneath side of the body. It usually takes about 45 days for the eggs to develop, hatch, and the young pillbugs to emerge from the pouch. The number of young per brood averages about 28 (range 5-79) and there are 1-3 broods per year. Within 24 hours of leaving the pouch the young molt, again at 14-18 days, and then irregularly thereafter depending on food availability. Adults may live about 2 years, possibly longer.
Pillbugs are confined to areas of high moisture because they lack both a closing device for their respiratory system and an outer waxy layer on the exoskeleton to prevent excessive water loss. Their nocturnal habit also reduces water loss.
Habits of Pillbugs (Rollie Pollies)
Pillbugs are inactive and remain hidden under objects during the day to reduce water loss. During the day, they can be found around buildings in such places as under trash, boards, rocks, flower pots, piles of grass clippings, flower-bed mulches, and other decaying vegetation.
They occasionally enter buildings via door thresholds, especially homes with sliding-glass doors on the ground level. Indoor invasion typically means that there is a large population immediately outside the building. They usually do not survive indoors for more than a couple of days unless there are high moisture conditions and a food supply present.
Pillbugs are scavengers and feed on decaying organic matter, usually plant material but occasionally animal. They cause no damage and are considered a nuisance pest indoors. Outdoors, they occasionally injure young plants.
Control of Pillbugs (Rollie Pollies)
The key to controlling pillbugs is to reduce or eliminate the moist areas which make their survival possible. For example, remove piles of grass clippings and leaves, store boxes, lumber, firewood, and flower pots off the ground, and provide adequate ventilation in crawl spaces. Indoors, they can be removed with a vacuum.
Application of appropriately labeled residuals can be made to building foundation walls, perimeter flower and/or ornamental plant beds, unfinished basements, and crawl spaces. Wettable powder and microencapsulated formulations are best, but dusts are also good in drier crawl spaces.
What do Pillbugs (Rollie Pollies) look like?
Introduction to Springtails
Their common name comes from the fact that most species have a furcula/springlike structure which allows them to jump; a 3/16″ (5-6 mm) long springtail can jump 3-4″ (75-100 mm). They are nuisance pests that are attracted to areas of high moisture. Springtails are worldwide in distribution with over 675 species occurring in the United States and Canada.
Recognition of Springtails
Adults mostly about 1/32-1/8″ (mostly 1-3 mm; range 0.25-10 mm) in length; body elongate or subglobular and soft, wingless. Color usually whitish or gray, sometimes purple, blue, green, yellow, or orange. Head with mouthparts chewing; some- times modified for sucking or filtering; eyes small, no more than 8 facets each; and ocel- li present or absent. Antenna short, 4- to 6-segmented. Abdomen 5- or 6-segmented, usually with a ventral forked structure (furcula) attached on 4th segment, furcula at rest folded forward and held by a clasplike structure (tenaculum) on 3rd segment, and with a small tubular structure (collophore) on 1st segment. Legs slender, small, and unmodified.
Immatures are externally similar to adults.
Similar Groups of Springtails
(1) Wingless members of other insect orders all lack a forked furcula and colophore; in addition, 1st instar millipedes (class Diplopoda) lack legs on 1st segment behind head, mites and ticks (class Acari) lack antennae and usually have 4 pairs of legs, 1st instar myriapods (class Pauropoda) have branched antennae, and wingless Homoptera (scale insects, aphids, etc.) and wingless psocids (order Psocoptera) with abdomen of more than 6 segments and antennae long.
Representative Species of Springtails
- Entomobrya nivalis Linnaeus; family Entomobryidae. Body elongate, body scales absent; head with a dorsal spot and all body segments striped; antenna inserted on front half of head, 4-segmented with 3rd segment much shorter than 4th; 1st thoracic segment dorsally much reduced, indistinct; abdominal segment 4 middorsally at least twice as long as segment 3; found worldwide.
- Folsomia quadriculata (Packard); family Isotomidae. Body elongate; without stripes or marks; ocelli present; antenna inserted on front half of head, 4-segmented with segments 3 and 4 not subsegmented/subdividied; 1st thoracic segment dorsally much reduced, indistinct; abdominal segment 4 middorsally subequal to or shorter than segment 3, anus ventral; found in United States, Europe, northern Africa, and northern Asia.
- Heteromurus spp.; family Entomobryidae. Body elongate, body scales absent; antenna inserted on front half of head, 5-segmented; 1st thoracic segment dorsally much reduced, indistinct; abdominal segment 4 middorsally at least twice as long as segment 3; found worldwide.
- Isotomodes tenuis Folsom; family Isotomidae. Body elongate; without stripes or marks; ocelli absent; antenna inserted on front half of head, 4-segmented with segments 3 and 4 not subsegmented/subdivided; 1st thoracic segment dorsally much reduced, indistinct; abdominal segment 4 middorsally subequal to or shorter than segment 3, anus ventral; found in United States and Canada.
- Proisotoma frisoni; family Isotomidae. Body elongate; body mostly darkened; antenna inserted on front half of head, 4-segmented with segments 3 and 4 not subsegmented/subdivided; 1st thoracic segment dorsally much reduced, indistinct; abdominal segment 4 middorsally subequal to or shorter than segment 3, anus terminal; found in United States and Canada.
- Siera platani (Nicolet); family Entomobryidae. Body elongate, with body scales; body marked with blue; antenna inserted on front half of head, 4-segmented with 4th segment not annulate (subdivided); 1st thoracic segment dorsally much reduced, indistinct; abdominal segment 4 middorsally at least twice as long as segment 3; preapical segment (dens) of furcular branches with ventral preapical scales; found worldwide.
- Tomocerus spp.; family Entomobryidae. Body elongate; body white or yellow, rarely brown, with silvery white to shiny black scales; antenna inserted on front half of head, 4-segmented with 4th segment much shorter than 3rd, and 3rd and 4th segments subsegmented/subdividied; 1st thoracic segment dorsally much reduced, indistinct; abdominal segment 4 less than twice as long as segment 3; found worldwide.
Biology of Springtails
Sperm transfer is indirect, with males depositing a stalked, globular spermotophore on the ground/surface which is picked up later by a female. Eggs are laid singly or in clusters in moist situations and this usually occurs several times. There are usually 5-10 molts before becoming an adult. Adults continue to molt throughout their life, with some species molting up to 50 times, although there is no increase in size after the 15th molt. Developmental time (egg to adult) usually requires 2-3 months, but it varies greatly with species and temperature; range from 1 week to over 2 years.
Most springtail species lack a trachael (breathing tube) system so respiration is through the cutcicle (=cutaneous). This also means that water passes readily through the cuticle. Entomobrya nivalis has been reported as causing an itching dermititis in humans. Seira platani, E. griseoolivata (Packard), and Orchesella albosa Guthrie have been reported as infesting human hair, and the latter as also infesting pubic areas, but without causing dermatitis.
Habits of Springtails
Springtails inhabit only moist or damp areas because they can rapidly lose water through their cuticle. Most species occur in the soil and in enormous numbers, such as up to 50,000 per cubic foot (0.03 cu m) of forest litter or up to 30,000/10.9 sq ft (1 sq m) in planted fields.
They often invade structures in search of moisture when their habitat becomes dry. They can enter through door thresholds, around utility pipes, through window screens, etc. They are frequently brought into structures, including offices, in potted plants. They are attracted to lights.
Springtails feed on decaying vegetation, fungi, bacteria, pollen, algae, lichens, arthropod feces, and carrion.
Indoors, they are commonly found in the high-moisture areas occurring in bathrooms and kitchens, damp crawlspaces and basements, and damp wall voids. They can often be found trapped in sinks and tubs. Moldy bedding, mattresses, couches, and stuffed chairs have been found to support large infestations. If mildew can be smelled, springtails may be a problem. In offices, the most common source is potted plants.
Outdoors, sources include leaf litter, mulch, under debris on the ground, firewood or logs on the ground, decaying railroad ties and landscape timbers, etc.
Control of Springtails
The best control is simply to dry out the site of infestation and the springtails will die or leave. High numbers of springtails can often be quickly reduced with a vacuum. If the area cannot be dried out, then the application of an appropriately labeled pesticide may be required.
What do Springtails look like?
Introduction to Boxelder Bugs
The common name reflects the fact that this species is a major pest of boxelder trees, Acer negundo Linnaeus. Boxelder bugs are primarily a nuisance pest because they enter structures to overwinter. This species is native to the western states. It is now found from eastern Canada, throughout the eastern United States, and west to eastern Nevada wherever boxelder trees are found.
Recognition of Boxelder Bugs
Adults about 1/2″ (11-14 mm) long; elongate-oval, somewhat flattened with head narrower than pronotum. Color black with reddish lines on dorsum, pronotum with margins and median line reddish, and basal half of wings with reddish margin. Head with ocelli present; mouthparts piercing-sucking, forming a beak held beneath body when not in use. Antenna 4-segmented, about half body length. Wings with outer membraneous (like cellophane) part many veined. Scent glands (opening on each side of thorax between 2nd and 3rd pair of legs) absent.
Nymphs similar to adults but lack wings although wingpads may be present, and bright red in color.
Similar Groups to Boxelder Bugs
(1) Western boxelder bug (Boisea rubrolineata) shorter, averaging 3/8″ (10 mm) long, basal half of wing with red margin and 3 longitudinal red stripes, and found in Nevada, Arizona, Texas, the Pacific Coastal states, and British Columbia.
(2) Small milkweed bug (Lygaeus kalmii) with pronotum lacking median red line, head with red mark between eyes, and membraneous tip of wings with only 4 or 5 veins.
(3) Golden raintree or red-shouldered bug (Jadera haematoloma) black wih slight gray luster, lateral pronotal margins widely reddish, no other pale markings present.
(4) Red bugs or stainers (Pyrrhocoridae) lack ocelli and front femora usually enlarged/swollen.
(5) Leaffooted bugs (Coreidae) with well-developed scent glands and hind tibiae often expanded and leaflike.
(6) Seed bugs (Lygaeidae) have membraneous part of wings with only 4 or 5 veins and front femora usually enlarged/swollen.
Biology of Boxelder Bugs
The overwintering adults emerge from hibernation and the females lay clusters of straw-yellow eggs on stones, leaves, grass, shrubs, and trees, especially in the bark crevices of boxelder trees. These eggs turn red as the embryos develop and hatch in about 2 weeks. These nymphs feed on fallen boxelder seeds and later on new leaves, going through 5 instars. In the warmer regions of the United States, there are 2 generations per year.
Habits of Boxelder Bugs
The overwintering adults emerge from hibernation when the boxelder buds open and fly back to their host trees, typically in late April to early May. They first feed on the fallen boxelder seeds and later move to the female boxelder trees when the seeds begin to form, feeding on the newly developing leaves.
The primary host plant is the seed-bearing (female) boxelder tree, but they also occur on seed-bearing silver maple trees, Acer saccharinum Linnaeus. They do not feed on the male trees. Occasionally, they will feed on the fruits of plum and apple trees.
In the autumn, boxelder bugs become gregarious and congregate on the south side of rocks, trees, and buildings where the sun hits. After large masses congregate, they may fly to nearby buildings to hibernate for the winter.
Inside, boxelder bugs are primarily a nuisance pest. However, their fecal material may cause a red stain, resulting in discoloration on curtains, drapes, clothing, and other resting places. When crushed or handled roughly, they produce a strong, disagreeable odor. They occasionally “bite” people, causing a skin irritation and producing a red spot similar to a small ulcer.
Control of Boxelder Bugs
No attempt should be made to kill these bugs in wall voids at any time because dead insect bodies attract dermestid beetles (larder beetles, carpet beetles, etc.). Dermestid larvae wander and readily enter the living space, causing numerous complaints. Instead, wait until summer when all live overwintering adults are out of the wall voids. Then follow the outside control measures given below. However, temporary relief is possible by using a vacuum to remove the bugs and sealing their entryways into the living space.
Control begins outside. Reducing the outdoor population of boxelder bugs is highly recommended. Reduction is achieved by spraying infested trees with the application timed to kill the young 1st generation nymphs and then again for those of each succeeding generation. Such spraying requires special equipment and usually an ornamental license, so it is typically done by a private contractor.
Unfortunately, on occasion some or all of the infested trees may not be on your customer’s property. In this case, the neighbors should be educated about the problem in an attempt to secure their cooperation. Regardless, use of preventative physical and chemical barriers aimed at adults before they congregate and attempt to enter buildings is recommended. Physical barriers involve exclusion. Although total exclusion is probably not possible, all vents (roof, overhang, weepholes, etc.) should be screened with at least 16-mesh screening. Caulk (silicone based is recommended) around cable entrances, windows, doors, overhands, facia boards, etc. Installation of closable chimney caps may be advisable. These steps should be taken in June or July.
Preventative chemical barriers involve applying a highly repellent, long-lasting residual to all outside vertical walls and the adjacent overhang; microencapsulated pyrethroids or pyrethrins, or pyrethroid wettable powder formulations work best. This application is made just before the last seasonal generation of adults emerge; if in doubt, check with your cooperative extension agent. Only one such application is required but its timing is crucial to its effectiveness. In the northeast, this application should be made between 15-30 August.
If adults have already begun to congregate and attempt entry into buildings, it may be too late for preventative action. The best solution is physical removal with a good shop-type vacuum. Then treat the outside walls as described above.
Temporary but immediate indoor relief can be achieved by removal with a vacuum. Then to prevent the entry of more adults, seal the possible routes of entry. Use paintable silicone caulk and/or expandable foam to seal. Such routes include around window pulleys (seal with tape or steel wool), window frames, door frames, baseboards, etc. For electrical outlets and switch boxes and heating duct and return-air vents, remove the coverplate, seal, and replace. For light fixtures and ceiling fans, remove the fixture to its base plate, seal, and replace.
What do Boxelder Bugs look like?
Introduction to the Ladybug (Ladybird/Lady Beetle)
Since lady is defined as “a woman of good family, social position, breeding, etc.,” this may refer to the fact that most species of this beetle family are highly beneficial insects; only 3 of 475 United States species are not beneficial. Some species have a habit of overwintering in structures and are therefore nuisance pests. Ladybugs are found worldwide with about 475 species occurring in the United States and Canada.
The multicolored Asian lady beetle, Harmonia axyridis (Pallas), is known to cause allergic reactions and aggravate asthma in some people. Also, about 42% of the people surveyed in Ohio reported receiving bites. In addition, they exude a viscous yellow, foul-smelling defensive compound when disturbed that may stain whatever it contacts.
Recognition of the Ladybug (Ladybird/Lady Beetle)
Adults about 1/32-3/8″ (0.8-10 mm) long; shape distinctive, broadly oval to nearly round, strongly convex dorsally, nearly flat ventrally. Color red, orange, yellow, brown, or shiny black, usually with various markings including white spots; often bright yellow, red, or orange with black markings or black with yellow, orange, or red markings. Head partly to completely concealed from above. Antenna short to usually very short, 8-11 segmented, with weak club of 3-6 segments. actually 4-4-4 (3rd segment minute).
Larvae look like tiny flat alligators, often with numerous spines and/or wartlike structures; color usually blackish, some with red, orange, or yellow spots or bands; some species secrete a white waxy material which makes them resemble mealybugs.
Similar Groups to the Ladybug (Ladybird/Lady Beetle)
(1) Tortoise beetles (Chrysomelidae) with tarsi appearing 4-4-4, actually 5-5-5 with minute 4th segment.
(2) Handsome fungus beetles (Endomychidae) have base of pronotum with 2 lengthwise grooves and usually black with red or orange.
(3) Marsh beetles (Helodidae) with antenna threadlike or sawtoothed and tarsi 5-5-5 with 4th segment lobed beneath.
(4) Shining mold beetles (Phalacridae) with antennal club distinct, 3-segmented, tarsi apparently 4-4-4 (actually 5-5-5), and brown or black with no markings.
(5) Other similarly shaped beetles (order Coleoptera) with a distinct antennal club and/or tarsi different.
Representative Groups of the Ladybug (Ladybird/Lady Beetle)
- Multicolored Asian lady beetle, Harmonia axyridis (Pallas). Adults typically with pronotum black with wide ivory lateral/side margins and basal median marks yielding a dark M-shaped (when viewed from rear) or W-shaped (when viewed from front) pattern, elytra mustard yellow to dark reddish orange, each usually with several black spots but spots sometimes indistinct or absent; length about 1/4-3/8″ (6-10 mm); found throughout most of United States and southern Canada.
- Convergent lady beetle, Hippodamia convergens Guerin-Meneville. Adults with head, pronotum, and legs black, pronotum with a whitish margin and centrally with 2 convergent whitish lines, elytra red, each with 6 black marks with anterior 3 smaller than posterior 3 but varying to elytral spots almost absent; length about 1/8-1/4″ (4.2-7.3 mm); found throughout the United States and southern western Canada.
- Ninespotted lady beetle, Coccinella novemnotata Herbst. Adult with head black with pale band between eyes, pronotum black with pale yellowish front and side margins, elytra orange to reddish yellow each with 4 black spots but varying to elytral spots almost absent, scutellum (triangular piece between elytral bases) black and black extending into elytra; length about 3/16-1/4″ (4.7-7.0 mm); found throughout the United States except for coastal North Carolina southward to west Florida peninsula and from southern Louisiana west through central Texas to southwestern New Mexico, and in southern Canada but extending far northward in western Canada.
- Spotted lady beetle, Coleomegilla maculata (DeGeer). Adults elongate, somewhat flattened; color red or yellowish orange, head with black margins, pronotum with 2 black spots, and 6 or 7 black spots on each elytron; length about 1/8-3/8″ (4-8 mm); found from Ontario through Florida, west to Minnesota and Texas, and west along the Mexican border through southern California.
- Twicestabbed lady beetle, Chilocorus stigma (Say). Adults black except pronotal front and side margins, spot on each elytron, and abdomen red or yellow; length about 1/8- 3/16″ (3.75-5 mm); found east of the Rocky Mountains and adjacent southern Canada.
- Twospotted lady beetle, Adalia bipunctata (Linnaeus). Adults typically with pronotum black with wide ivory lateral/side margins and basal median mark yielding dark M-shaped pattern, elytra orange, each with a median black spot; length about 1/8-3/16″ (3.5-5.2 mm); found from Labrador, Canada, to Alabama, west through Alaska and California.
Biology of the Ladybug (Ladybird/Lady Beetle)
The overwintering adults emerge from hibernation and the orange eggs are laid on end in single or multiple groups of 12 on plants infested by aphids (plantlice), mealybugs, scale insects, etc. Larvae pass through 4 molts. Mature larvae attach to leaves by the tip of their abdomens and pupate without forming a cocoon.
Habits of the Ladybug (Ladybird/Lady Beetle)
Larvae and adults are predaceous on aphids, mealybugs, mites, scale insects, other soft-bodied insects, and their eggs, making them very beneficial insects. A few species are leaf feeders and are important plant pests, for example, the Mexican bean beetle, Epilachna varivestis Mulsant.
In the autumn, adults seek protected places in which to overwinter. These may include under leaves, rocks, and landscape timbers, but also inhabited structures. Unfortunately, the release and use of lady beetles for biological control by organic gardeners, the USDA (especially the multicolored Asian lady beetle for control of aphids on pecan trees and fruit crops), and others has greatly increased the incidence of their entering structures to overwinter by artificially increasing their numbers.
The aggregation behavior in lady beetles has been described as a 5-step process as follows:
- The beetles only fly in strong, directional afternoon sunlight and first orientate to large visual landmarks (macrosites) such as buildings (2-story structures preferred) or mountain tops that can be visually detected at a distance. They orientate to features that have a high contrasting silhouette such as shadows cast by overhangs, gutters, downspouts, windows, and doorframes on a white house. A black-on-white linear contrast is the most attractive.
- They land on the surface of the macrosite.
- They determine if it contains an acceptable substrate.
- The beetles start a local, walking search for cracks, crevices, or other acceptable microsites for overwintering shelter, often crawling upward.
- Finally, they aggregate and settle into the sheltered space.
The beetles may take flight and repeat the entire process if appropriate overwintering shelter is not located. Other things that influence this process include air currents, the visual background of the structure, trees that may obscure their line-of-sight, the proximity of late season aphid-infested vegetation, and the compass orientation of the wall(s) with the warmest wall being favored (usually those facing south to west).
Control of the Ladybug (Ladybird/Lady Beetle)
Because lady beetles are beneficial and are not of any health or structural importance, no direct control is recommended. Practice exclusion by the use of preventative physical barriers aimed at adults before they congregate and attempt to enter structures and educating the customer are the best solutions.
Physical barriers involve exclusion. Although total exclusion is probably not possible, all vents (attic gable, roof, overhang, weep holes, etc.) should be screened with at least 16-mesh screening. Seal (silicone-based is sealant recommended) around cable entrances, windows, doors, overhangs, facia boards, etc. Installation of remotely closable chimney caps (spring-loaded with a cable running through the flue pipe and a lock-catch in the fireplace) may be advisable. These steps should be taken in June or July.
No attempt should be made to kill these beetles in wall voids at any time because dead insect bodies attract dermestid beetles (larder beetles, carpet beetles, etc.). Dermestid larvae wander and readily enter the living space, causing numerous complaints. Instead, wait until summer when all live overwintering adults are out of the wall voids. Then follow the outside control measures given above. However, temporary relief is possible by using a vacuum to remove the beetles, and sealing their entryways into the living space.
Temporary but immediate indoor relief can be achieved by vacuuming, but the odorous liquid released by the beetles may necessitate the eventual replacement of the hose. To prevent the entry of more adults, seal the possible routes of entry with paintable silicone caulk and/or expandable foam. Entry points include around window pulleys (seal with tape or steel wool), window frames, door frames, baseboards, etc. For electrical outlets and switch boxes and heating duct and return-air vents, remove the coverplate, seal, and replace. For light fixtures and ceiling fans, remove the fixture to its base plate, seal, and replace. Most species can be harvested with insect light traps (ILTs) from problem areas such as attics and false-ceiling voids.
What do Ladybug (Ladybird/Lady Beetle) look like?
Introduction to Click Beetles
The common name comes from the beetle’s ability to click/snap and flip their body into the air when turned upside-down. The eyed click beetle, Alaus oculatus (L.), is our largest species and has two large eye spots on its pronotum. Click beetles are nuisance pests around structures because the adults are attracted to lights at night. The larvae are hard-bodied and are called wireworms. They feed primarily on the roots and other underground parts of grass, flowers, garden plants, and agricultural crops such as cereals, corn, beans, cotton, etc. Hence, many species are very destructive and are of economic importance. There are about 885 species in the United States and Canada.
Recognition of Click Beetles
Adults range from 1/16 to 1 3/4″ (1.5-45 mm; most at 3-20 mm) in length. Color usually black or brown, sometimes orangish and/or lightly patterned. Shape distinctive, elongate-narrow, somewhat flattened, usually parallel-sided, ends rounded or rear end moderately tapered; pronotum loosely joined to rest of body, with its rear corners prolonged backward into sharp points. Prosternum with front edge nearly always lobed and rear edge with a median elongate lobe extending rearward into a depression in the mesosternum; this arrangement along with the loosely jointed pronotum allow these beetles to click. Antenna close to eyes, usually sawtoothed, sometimes comblike. Tarsi 5-5-5.
Mautre larva 1/2-1 3/8″ (12-35 mm) long. Color shiny yellow to brown. Shape slender, cylindrical, unusually hard-bodied, wirelike. Legs well developed, ending in a clawlike structure.
Similar Groups to Click Beetles
(1) False click beetles (family Eucnemidae) with antenna not close to eyes, front edge of prosternum straight.
(2) Rare click beetles (family Cerophytidae) with trochanters very long, almost as long as femora.
(3) Throscid beetles (family Throscidae) more compact and broadest at base of elytra, prosternal process attached to mesosternum and not moveable, antenna often with loose 3-segmented club.
(4) Metallic wood-boring beetles (family Buprestidae) nearly always with metallic luster, especially on under surface.
(5) Other similar appearing beetles lack the clicking mechanism.
Biology of Click Beetles
Depending on the species, they overwinter as eggs, larvae, or adults. Some species complete their life cycle in one year, while others require 2 to 5 years. The eggs are laid singly in soil 1-6″ deep in the spring or early summer and hatch in 2-4 weeks. The larvae crawl through the soil looking for suitable plant material for food. There are always overlapping generations.
Habits of Click Beetles
Adults are best known for their ability to click/snap and flip their body into the air when turned upside-down, a process that will be repeated until they land on their feet. Adults live on the foliage of trees and shrubs, but a few live under loose bark or in decaying logs. Adults of most species are attracted to lights at night.
The larvae or wireworms feed on the underground parts of plants. Many species are very destructive and cause economic damage to lawns, garden plants, and agricultural crops. The larvae of some species live in decaying vegetation and a few species are predators on the larvae of other insects.
Control of Click Beetles
Lawns may need to be treated for moderate to severe infestations. A lawn and ornamental license is required in most states.
What do Click Beetles look like?
Introduction to Aphids (Plant Lice)
This is a large group (about 1,350 species in the United States and Canada) of soft-bodied insects, many of which are economic pests of trees, landscape plants, and agricultural crops. Aphids pierce the leaves, stems, and/or roots of plants and suck out the juices. They excrete a sticky, sweet liquid called honeydew that is sought after by ants and other insects. These are nuisance pests in structures, but outdoors, their honeydew can damage painted surfaces. They are usually brought in on cut flowers, potted plants, and Christmas trees.
Recognition of Aphids (Plant Lice)
Adults range from 1/8 to 5/16″ (4-8 mm) long. Body is soft, somewhat pear-shaped, usually pale or greenish, but may be reddish or blackish. Mouthparts piercing-sucking, with beak arising at back of head. Antenna 4- to 6-segmented, threadlike. Wings if present 4, usually clear, hind wing smaller, front wing with Rs present and M branched, and held vertical above body. Tarsi 2-segmented. Abdomen almost always with a pair of cornicles (dorsal tubular structures) near its rear.
Similar Groups to Aphids (Plant Lice)
(1) Psyllids (family Psyllidae) with abdomen lacking cornicles (dorsal tubular structures near its rear), antenna 10-segmented.
(2) Woolly and gall-making aphids (family Eriosomatidae) with lots of woolly or waxy material that may almost cover body; if winged, M in front wing unbranched; cornicles very small or absent.
(3) Pine or spruce aphids (family Chermidae) feed on conifers; abdomen lacks cornicles; if winged, front wing with Rs absent.
(4) Other small similar looking insects lack cornicles.
Biology of Aphids (Plant Lice)
Their life cycle is complex, but there are two primary types that involve differences in host plant needs. In the first type, a single species of host plant is involved. Eggs overwinter and hatch in the spring when the leaves and flowers start to open. The nymphs develop into wingless females that reproduce parthenogenetically (without fertilization). When winged females are produced, they fly to other plants of the same species and continue to reproduce. With the onset of winter, male and female sexual forms are produced, mate, and eggs are laid on the host plant. This is the typical life cycle of most aphids.
The second type involves the alternation of host plants. The first or primary host, starting with the overwintering eggs, supports the production of a series of parthenogenetically produced aphids. Early on, winged parthenogenetic females are produced that migrate to another host species, the secondary host, and start new colonies. Over the summer, a series of winged and wingless generations is produced. With the onset of winter, male and female winged forms are produced that return to the primary host. The winged parthenogenetic females then produce wingless sexual forms that mate with the males. The eggs produced overwinter and the cycle continues.
There are variations on this second cycle where more than two host plant species are involved. In some species of aphids, the female gives birth to live young (ovovivipary), where the eggs hatch within the female.
Habits of Aphids (Plant Lice)
Aphids feed on the leaves, stems, and/or roots of plants. With their mouthparts, they pierce the plant’s surface and suck out the juices. They then excrete a sticky, sweet liquid called honeydew from their anus that is sought after by ants and other insects.
These are nuisance pests in structures, but outdoors, their honeydew and/or the mildew that grows on it can damage painted surfaces, and their honeydew serves as a strong attractant to ants. They are usually brought in during warm weather on cut flowers from the yard, but winged adults may fly in through open doors, etc. In autumn, they are brought in on potted plants that were put outdoors for the summer. Then in the winter, they are often brought indoors on Christmas trees. These aphids normally pass the winter in clusters on the pine branches and their presence is usually not noticed immediately. However, as the infested pines begin to warm and dry out, the aphids begin to leave the tree (often enmass) and wander about in search of a more suitable plant to infest.
Control of Aphids (Plant Lice)
Screened doors and windows should prevent most flying forms from gaining entry. Plants near exterior doors should be inspected for infestation. Any infested plants should be treated with an appropriately labeled pesticide. Cut flowers are best returned to the outdoors immediately. The source of these cut flowers should be inspected and infested plants treated with an appropriately labeled pesticide. Potted plants that have been put outdoors during warm weather should be inspected before being brought back indoors. Christmas trees should be carefully inspected at the time of purchase and rejected if infested. If an infested tree is brought indoors, then it will have to be treated. An insecticidal soap or an appropriately labeled pesticide can be applied.
It should be noted that most states require the PMP to have a lawn and ornamental license to treat such plants and trees. In most cases, it is probably best to just advise the customer of what the problem is and what can be done to solve their problem.
What do Aphids look like? What does Plant Lice look like?
Introduction of House Fly
These flies receive the common name of house from being the most common fly found in and around homes, especially in the preautomobile era and in rural areas. It is not only a nuisance pest but of greater concern is its potential as a carrier of disease organisms, having been found to harbor over 100 different pathogenic organisms. It is worldwide in distribution, and is found throughout the United States.
Recognition of the House Fly
Adults about 1/8-1/4″ (4-7.5 mm) long, with female usually larger than male. Color dull gray; face with 2 velvety stripes, each silver above and gold below; thorax with 4 narrow black longitudinal stripes on dorsum; no pale spot behind head or on scutellum (rear tip of thorax); abdomen usually with sides pale at least near base. Mouthparts sponging. Females with eyes much more widely separated than on male. Wing with 4th (3rd long) vein (M) sharply bent forward near tip, towards and almost meeting 3rd vein at wing margin.
Mature larva about 1/4-3/8″ (7-10 mm) long; eyeless, legless, and tapering towards head from large rounded rear segment, head represented by 1 pair of dark hooks. Color cream but with greasy appearance. Posterior spiracles (breathing pores) slightly raised, spiracular area smooth, spiracular openings are sinuous/winding slits which are completely surrounded by an oval black ridge (peritreme) which has a dark donut-shaped structure (button or ecdysial/molting scar) attached to its inner margin.
Similar Groups to the House Fly
(1) Face fly (Musca autumnalis) have wing calyptera (flat basal lobe) with tuft of bristles; males with eyes almost touching (vs. well separated with parallel-sided frontal stripe between) and abdominal dorsum and sides entirely black in ground color with gray-and-black (vs. usually yellowish at sides) whereas, female with parafrontals (sides of front next to eyes) bright gray, nearly as wide as median frontal stripe (vs. often yellowish, about 1/3 as wide as frontal stripe).
(2) Flesh flies (Sarcophagidae) have only 3 dark longitudinal stripes on thorax, tip of abdomen usually red/pink, abdominal sides never pale.
(3) Stable (Stomoxys calcitrans) and false stable (Muscina stabulans) flies have wing with 4th (3rd long) vein curved towards 3rd vein but not sharply angled; in addition stable flies have piercing mouthparts and thorax with pale spot behind head while false stable flies have sponging mouthparts but a pale scutellum (rear tip of thorax).
(4) Cluster flies (Pollenia spp.) with golden hairs on thorax, thorax lacks 4 dark longitudinal stripes.
(5) Little house (Fannia canicularis) and latrine (F. scalahs) flies have wing with 4th (3rd long) vein straight.
(6) Other flies either lack 4 dark thoracic stripes, 4th (3rd long) vein sharply angled, and/or dull thorax and abdomen.
Biology of House Fly
The adult female lays her eggs (white, oval, 1/3271 mm long) singly but usually in clusters of 20-50 for a total of 75-150 per batch and will lay 5-6 batches in her lifetime totaling 350-900 eggs (maximum 2,387 in 21 batches). Eggs are laid in moist materials, hatch in about 8-20 hours, and the larvae (maggots) go through 3 instars in 3- 7 days at 70-90°F (21-32°C). The full-grown/mature larva seeks a cool, dry place to pupate, migrating up to 150 feet in 3-4 days. The pupa starts out yellowish and changes to black, this stage taking 3 days to 4 weeks depending on temperature and humidity. After emerging from the pupa, about 1 hour is spent drying the wings and hardening the body at 80°F (27°C), with normal activity starting at 15 hours. Depending on conditions, developmental time (egg to adult) may require as few as 6 days. There may be as many as 10-12 generations per summer. Adults usually live 15-25 days.
House flies are general feeders, being attracted to a wide variety of substances from excrement to human foods. Because of their sponging mouthparts, they can feed only on liquids. However, through regurgitation they are able to liquefy many desirable solid foods. Also, a house fly excretes and regurgitates whenever it comes to rest. This habit coupled with its many body hairs and bristles and the sticky pads at the base of the claws on each leg make house flies well adapted for transporting disease organisms.
House flies have been shown to harbor over 100 different kinds of disease causing pathogens, many of which are associated with filth. Such pathogens include those causing typhoid fever, cholera, diarrhea, dysentery, tuberculosis, anthrax, ophthalmia, polio, and salmonellosis, as well as parasitic worms. They have been shown to be disease pathogen transmitters via their vomit, feces, and contaminated external body parts.
Habits of the House Fly
Although house flies have been shown to migrate up to 20 miles, most stay within 1-2 miles/1.6-3.2 km (55-96% within 1 mile, 77-100% within 2 miles) of their release point or larval habitat if sufficient food is available. Females seek almost any warm, moist material with sufficient food for larval development for egg-laying purposes.
House flies are attracted to buildings by air currents and odors. Since their preferred temperature is 83°F (28°C), on cooler days they are attracted to the warm air currents coming out from around doors and windows and on warm days by the cooler air currents coming out. During the day, house flies tend to fly or rest less than 5 feet (1.5 m) from the ground on walls, floors, and various objects; optimal flying height is 30″ (0.8 m) above the ground/floor surface. At night they rest primarily above 5 feet (1.5 m) on ceilings, walls, electric wires, dangling light cords, edges/corners of buildings, plants, etc. Their night rest- ing places are usually near their daytime food sources.
Control of the House Fly
House fly control is a 5-step process which includes identification, inspection, sanitation, mechanical control, and insecticide application.
- Be sure that the problem is house flies.
- Inspection involves locating the fly breeding and larval developmental sites. It is sometimes helpful to do this at night when the flies are resting near their food and/or larval developmental sites. As with other filth/large flies (e.g., blow and flesh flies), house flies usually enter from the outside. Interior breeding sites are not common except in interior garbage rooms and compactors. Situations with interior breeding sites can be recognized because dozens of adults of the same species will emerge in relatively close succession.
- Sanitation involves the removal or elimination of the larval developmental sites. This may involve the timely emptying and cleaning of garbage receptacles to render breeding materials unavailable, or unsuitable by drying them out. The dumpster/compactor pad must be kept clean and dry, especially underneath the unit. All trashcans must have liners. Sanitation should eliminate the bulk of the fly problem so that mechanical and insecticidal measures will be more effective.
- Mechanical controls consist of garbage receptacles with tight-fitting closures that are kept closed except when being filled/emptied, tight-fitting windows and doors, windows securely screened if they can be opened, doors with self-closures, all holes through exterior walls for utilities, etc., sealed, all vents securely screened, etc., and the use of air curtains, insect light traps, sticky-surfaced traps, etc. The dumpster/compactor should be located as far away from the building as possible, and trashcans should not be located near building entrances. Insect light traps (ILTs) are particularly effective in reducing the number of flies indoors.
- Pesticide application involves using appropriately labeled products. Outdoors, this includes the use of boric acid in the bottom of dumpsters, treatment of landing zones on dumpsters/compactors, treatment of vertical walls adjacent to dumpsters and other breed- ing sites with a combination of an attractant and a microencapsulated or wettable powder formulation, treatment of both sides of door-wall junctions, treatment of the interior of trashcan covers, and the use of fly baits in protected situations near adult feeding sources. Indoors, ULV applications on a room-by-room basis may be required, with the low-oil formulations being more desirable.
What does the House Fly look like?
Introduction to Fruit/Vinegar Flies
The common name of small fruit fly comes from their small size and fondness of some species for fruits as egg laying and development sites. The name vinegar fly comes from the fact that they develop in the briny or vinegarlike liquids at the top of imperfectly sealed canned fruits and vegetables. Note that only flies of the family Tephritidae can properly be called fruit flies. Small fruit flies are nuisance pests but may act as disease vectors. The best known of these flies is D. melanogaster Meigen which has been used extensively in the study of heredity. They are world wide in distribution and are found throughout the United States.
Recognition of Fruit/Vinegar Flies
(Drosophila spp.) Adults about 1/8″ (3-4 mm) long, including wings. Color dull, tan to brownish yellow or brownish black, thorax sometimes mottled dark brown, abdominal terga (dorsal plates) often with darker rear cross-bands/margins; eyes usually bright red, but may be very dark red-brown. Antenna 3-segmented, with an arista (feathery bristle) on 3rd segment. Wing with costal vein (thickened front margin) broken (very thin places) twice, near end of humeral cross vein (short vein perpendicular to costa near wing base) and near end of R1 (1st vein behind costa). First hind tarsal segment long and slender, much longer than 2nd segment.
Mature D. melanogaster larvae are about 1/4-3/8″ (7-8 mm) long, eyeless, legless, and tapering towards head from large rounded rear segment, head represented by 2 dark hooks. Color near white except mouth hooks black and tips of posterior terminal abdominal spiracles (breathing pores) yellowish. Posterior spiracles at end of short stalks/fleshy tubes which are in contact or joined at their bases. Other species may have posterior spiracle stalks dark and/or have whorls of setae (hairs) at the ends, and/or have the bottom side of abdomen with darkened cross bands (setulae).
Similar Groups to Fruit/Vinegar Flies
(1) Small dung flies (Sphaeroceridae) with 1st hind tarsal segment broad and shorter than 2nd segment, wing with costal vein (thickened front margin) broken 3 times (additional break before humeral cross vein).
(2) Humpbacked flies (Phoridae) with humpbacked appearance, wing with strong/dark basal front veins (costal area) and 4-5 weaker (less distinct) unbranched oblique veins, hind femora flattened.
(3) Moth/drain/sewage flies (Psychodidae) have body and wing veins densely covered with hairs.
(4) Fungus gnats (Mycetophilidae) and darkwinged fungus gnats (Sciaridae) are slender, long legged mosquitolike, with elongated coxae, wing costa (front margin) unbroken, antenna with many segments and lacks an arista/bristle.
(5) Other small flies either lack antenna with a feathery bristle and/or wing with a twice broken costal vein.
Representative Species of Fruit/Vinegar Flies
- Drosophila melanogaster Meigen; Small (about 1/8″ or 3 mm long), light tan with abdomen with blackish cross-bands at rear of each tergum (dorsal plate) and grayish below, with bright red eyes; wing with 3rd (R4+5) and 4th (M1) longitudinal veins parallel or slightly convergent at wing margin; distributed worldwide.
- Drosophila repleta group; slightly larger (about 1/8″ or 4 mm long) than D. melanogaster, with a dark brown mottling on thorax, with dark red eyes; wing with 3rd (R4+5) and 4th (M1) longitudinal veins divergent at wing margin; distributed worldwide.
Biology of Fruit/Vinegar Flies
Adult females lay their eggs (average about 500) near the surface of ferment- ing fruits and vegetables, near the cover crack of imperfectly sealed containers of such materials, or in decaying organic matter. The eggs hatch in about 30 hours. The larvae develop in the briny vinegarlike liquids of the fermenting materials where they feed near the surface and primarily on the yeast, for about 5-6 days. Prior to pupation, the larvae crawl to drier areas of the food or elsewhere. The brown seedlike sheath containing the pupa (the puparium) is formed from the last larval skin/exoskeleton. The newly emerged adults mate in about 2 days. The life cycle (adult to adult) may be completed in 8-10 days at 85°F (29°C). Their reproductive potential is enormous.
Habits of Fruit/Vinegar Flies
Small fruit flies are attracted primarily to fresh fruits and vegetables and those fermenting because of yeast, and to decaying organic matter; some species are attracted to human and animal excrement. The larvae develop primarily in liquids near the surface but seek drier areas for pupation.
- Drosophila melanogaster. Prefers fruits and vegetables in early stages of decay/fermentation. Common in grocery stores, fruit packing facilities, commercial kitchens, homes, and other places where fresh fruits and vegetables are common. Materials commonly infested include bananas, grapes, peaches, pineapples, tomatoes, mustard pickles, potatoes, onions, etc. and fermenting liquids such as beer, cider, vinegar, and wine. Materials lose their attractiveness to this fly when they begin to decay because of bacteria and fungi.
- Drosophila repleta group. Prefers decaying organic matter. Commonly found breed- ing on the biofilm (slimy substance) of dirty drains. Occasionally, erroneously referred to as the drain fly. More common in commercial kitchens than D. melanogaster, but occasionally found together.
Newly emerged adults are attracted to lights. Because of their short life cycle of 8-10 days, they can exploit many temporarily available developmental sites such as sour mop and broom heads, fruit under a table or cabinet, fruit left out in a bowl, etc. Dishwater and mop water full of food particles can accumulate on surfaces and/or in crevices and ferment, providing ideal fly breeding conditions.
Adults tend to hover in small circles. The common darkeyed vinegar flies, such as the more robust and almost black D. repleta Wollaston, tend to spend most of their time sitting on vertical surfaces.
Because of their small size, many species are able to penetrate ordinary screens.
Control of Fruit/Vinegar Flies
The key to small fruit fly control is breeding site elimination. The presence of adult flies usually means that larvae are developing in some nearby fermenting material. If the flies are coming from outdoors, reducing the screen mesh size can be helpful because most species can penetrate ordinary screens. The number of adults can be reduced through the use of baited jar traps. The attractants may work better on some species than for others, so proper identification is critical.
Inside of buildings, the application of microbial formulations is the preferred method of control for species that breed on the biofilm in drains and the decaying organic matter that accumulates in hard-to-reach/access areas under equipment, etc. Foam delivery is the most effective method to use. The application of microbial floor cleaners is very effective in reducing or eliminating organic debris that accumulates under baseboards, broken floor tiles, and loose/missing tile grout; it will also greatly reduce the organic matter in mop heads that are not properly maintained.
Adults can easily be killed with an appropriately labeled aerosol, or ULV application. However, unless proper sanitation has been practiced, such relief will only be temporary, lasting only until new adults emerge.
What do Fruit Flies look like?
INTRODUCTION
These flies get the common name of moth fly from their fuzzy appearance, their bodies and wings being very hairy. The drain/filter/sewage fly common names are from places or situations that represent typical breeding and developmental sites. Although usually thought of as nuisance pests, there have been cases where inhalation of their body parts caused bronchial asthma. Moth flies are found throughout the United States and most of the world.
RECOGNITION
Adults about 1/16-3/16″ (1.5-5 mm) long, delicate and fuzzy. Color pale yellowish to brownish gray to blackish, depending on the species. Antennae 12- to 16- segmented, each segment bulbous and with a whorl of long setae (hairs). Wings broadly oval, pointed apically, veins and margins hairy, and held rooflike over body at rest. Non-biting. In addition, ocelli absent, costal vein continued around wing, longitudinal veins equally developed, and cross veins restricted to basal 3rd of wing.
Mature larvae about 1/8-3/8″ (4-10 mm) long, eyeless and legless. Subcylindrical in form, with head narrower than body and terminal rear (apical) segment narrow, forming a short hardened (sclerotized) breathing tube. All or some body segments with narrow, transverse, sclerotized, strap-like bands (usually 2 or 3) on their dorsum. Color pale with head, dorsal bands, and apical breathing tube dark.
SIMILAR GROUPS
(1) Sand flies (Psychodidae, subfamily Phlebotominae) with 2nd longitudinal vein of wings branching distant from wing base (moth flies with it branching near wing base), legs long and slender, wings held together above body at rest, females bite.
(2) Mosquitoes (Culicidae) with wings long and narrow, veins and wing margin covered with scales.
(3) Other flies lack dense hair on body and on wing veins and margin.
REPRESENTATIVE SPECIES
- Pacific drain fly, Psychoda phalenoides (Linnaeus). Adult about 1/8″ (2-2.3 mm) long; wings brownish gray; antenna 15-segmented, with segments 13 and 14 each half the size of 12th segment; found along the Pacific Coast from southern California to Alaska.
- Psychoda alternata Say. Adult about 1/16″ (2mm) long; body light tan, wings lighter but faintly mottled with black and white, wings with brown spots at ends/tips of veins; antenna 15-segmented but appearing 14-segmented (segments 13 and 14 fused), segment 15 small, buttonlike; ranges from Florida to Massachusetts and westward to Washington and California.
- Psychoda satchelli Quate is pale yellowish and antenna 14-segmented with segments 13 and 14 subequal in size; ranges from Georgia to Quebec and westward to Alaska and California.
- Psychoda cinerea Banks is pale yellowish with 16-segmented antenna having terminal 3 segments equal in size; eastern United States.
- Telmatoscopus albipunctatus (Williston) is brown or blackish, white hairs on thorax, and white spots at tips/ends of wing veins; antenna 14-segmented; found throughout the United States.
BIOLOGY
Adult females of Psychoda alternata lay their 30-100 eggs in irregular masses on the surface of the gelatinous film which covers filter stones of sewage treatment plants or which lines the water-free portions of drain pipes. Both the larvae and pupae live in this gelatinous film with their breathing tube(s) projecting through the film. The larvae feed on the algae, bacteria, fungi, microscopic animals, and sludge of this film. At 70°F (21 °C) eggs hatch in 32-48 hours, the larval stage lasts 8-24 days, and the pupal stage lasts 20-40 hours. The developmental time (egg to adult) is 7-28 days, depending on conditions. Adults mate within a few hours of emergence, are attracted to lights, and typically live about 2 weeks.
Although they may breed in sewage, apparently they do not transmit human diseases. However, in South Africa, there have been cases of bronchial asthma where the inhalant allergen consisted of dust composed of dead moth fly body parts.
HABITS
Because of their small size, moth flies are able to penetrate ordinary screens. Moth flies are weak fliers, so indoors they are usually seen crawling on walls or other surfaces. When they do fly, it is only for short distances of a few feet and their flight is in characteristic short, jerky lines. During the day, they typically rest on vertical surfaces near drain openings indoors and in shaded areas outside. Their greatest activity is in the evening when they can be seen flying or hovering above drain openings indoors or sewage filter beds, etc. outside.
Typically, only a few adults are seen at a time in structures because the adult flies live only about 2 weeks but are continually being replaced with newly emerging flies as they die. However, large numbers of adults usually means that an outside source such as a sewage treatment plant is involved. Even though they are weak flies, they can be carried for distances of 1 mile (1.6 km) or more by the wind.
CONTROL
After proper identification, a thorough inspection is required to find the breeding site. Places to check include: slimy drains, sewer leaks or backup, dirty garbage cans, saucers under potted plants, bird baths or feeders, clogged roof gutters, clogged storm drains, air conditioners, cooling towers, moist compost, rain barrels, and septic tanks. If large numbers of flies are seen, be sure to check for nearby sewage treatment plants, especially upwind from the structure. Inside of buildings, the application of microbial drain formulations are the preferred method of control, with foam delivery being most effective. An ULV application can be used to kill large numbers of adult flies, but only the elimination of the breeding site(s) will provide long-term control.
When large populations of these flies are breeding in sewage filter beds, control usually consists of the periodic flooding for a minimum of 24 hours to kill larvae and pupae; eggs are unaffected. In addition, weed control should be practiced to remove adult roosting sites and any adjacent vertical surfaces should be treated with an appropriately labeled pesticide. Microencapsulated and wettable powder formulations are particularly effective.
What does the Moth (Drain/Filter/Sewage Fly, Psychodid) look like?
Introduction to Bumble Bees
The common name of bumble bee possibly comes from their rather large, clumsy appearance and/or the buzzing sound they make as they fly. In the urban setting, bumble bees do not usually nest in structures but are of concern because of their abundance around the many flowering plants typical of yards, and because they can sting. There are about 51 species (45 in Bombus, 6 in Psithyrus) in the United States and Canada, and as a group they are found throughout the United States.
Recognition of Bumble Bees
Adult worker body length about 1/4-1″ (6-25 mm), queens about 3/4-1″ (17-25 mm) long; robust in form. Color black with yellow (rarely orange) markings; with overall fuzzy/hairy appearance, including top surface of abdomen. Head with distinct space between base of compound eye and base of mandible. Antenna 12-segmented in female, 13-segmented in male. Hind tibia with apical spurs. Front wing with 2nd submar- ginal cell more or less rectangular, about as long as 1st submarginal cell. Hind wing lacks a jugal lobe (lobe on rear margin near body). Male abdomen with tip rounded; female abdomen with tip pointed, stinger relatively smooth, with small barbs.
In addition, female Bombus with hind tibia modified into pollen basket (surface bare and polished, marginal hair fringe) whereas, Psithyrus lacks pollen basket, hind tibia slender.
Similar Groups to Bumble Bees
(1) Carpenter bees (Xylocopa spp.) with top surface of abdomen largely bare and shining, front wing with 2nd submarginal cell triangular, and hind wing with jugal lobe (lobe on rear margin near body).
(2) Some robber flies (Diptera: Asilidae) with only 1 pair of wings.
(3) Some hawk moths (Lepidoptera: Sphingidae) with siphoning mouthparts.
Biology of Bumble Bees
Bumble bees are social insects which live in nests or colonies. The adults are represented by workers (Psithyrus spp. lack workers) which are sterile females, queens, and males (drones) which come from unfertilized eggs and usually appear in late summer.
Typically, only inseminated queens over winter and do so underground. In the spring, the queens of Psithyrus species wait until the Bombus nests are moderate in size and then parasitize them. The Bombus queens select a suitable subterranean cavity or surface grass clump as a nesting site. Then the Bombus queen fashions a honey pot of wax scales near the nest entrance into which she regurgitates nectar. Next she makes a pollen clump on the nest floor and lays 8-10 eggs on it. The queen will periodically add pollen and nectar to the peripheral edges of the clump, and eventually more eggs. Developmental time (egg to adult) is 16-25 days, with 4 larval molts. Workers live about 2 weeks. Most first brood workers are small due to nutrition. The queen will increase the number of eggs laid as the number of workers to care for them increases.
During the summer, parasitism may eliminate up to 50% of the colony’s workers each week. However, a mature bumble bee nest ultimately contains about 50-400 bees at any given time; the largest known nest contained 756 bees and 385 brood (larvae and pupae).
The nest temperature is regulated to about 86° F (30° C). This thermoregulation is accomplished by the bee relaxing the 3rd axillary muscle to its wings which unhinges the wings from the main power-producing thoracic muscles. Then contractions of these large muscles produces body heat without wing movement.
In the late summer only males (drones) and new queens are reared in the nest. Once these new females emerge, they mate and find a suitable place to over winter. The males, workers, old queen, and any virgin new females die with the onset of cold weather.
Habits of Bumble Bees
Depending on the Bombus species, the overwintering queen will select an appropriate nesting site the following spring. The queen of some Bombus species locate a dark cavity at least 3/4″ (2 cm) high by 1 1/8″ (3 cm) wide containing fine plant fiber; such a nest is usually underground and often an abandoned mouse nest. Queens of other Bombus species select a dense clump of grass on the surface for a nest, adding grass on top. The queens of Psithyrus species are all parasitic on Bombus nests, so they bide their time until the Bombus nests are moderate in size and can therefore support them. They then enter the nest, kill the Bombus queen, and take over the nest using the Bombus workers to care for her young. Bombus queens of later emerging Bombus species sometimes also parasitize the nests of earlier emerging Bombus species.
Bumble bees foraging for nectar fly at 7-12 mph (11-20 km/hr) and spend only 2-4 minutes inside the nest between trips. Probably they will travel at least 3 mi (5 km) if necessary for nectar. They orientate by the sky’s polarized light via their 3 ocelli, so they can forage before and after light when objects and landmarks are not visible. They use their theromoregulation procedure to warm up flight muscles before the sun rises and to also forage when temperatures are below 50° F (10° C; lowest observed flight at 26° F/-3.60 C) whereas, most bees stop foraging at 61° F (16° C). Each worker forages independently, and bumble bees never exchange food. Old cocoons are used to store both pollen and nectar. Only enough food (honey and pollen) for a few days is stored at any given time which helps discourage nest predation by skunks, foxes, etc.
Defense is usually accomplished using their relatively smooth stingers that can be used over and over. Some species will also spray feces, and some cover the intruder with regurgitated honey. People sensitive to insect venom should exercise care around bumble bee nests.
Control of Bumble Bees
Bumble bees are considered beneficial insects because they pollinate the flowers of many plant species. However, if their nest is located in or close to an occupied structure or recreational area, then control is warranted. During the day find the location of each nest by observing where the bees disappear into the ground, grass clump, or structure. At night using background light and while wearing a bee veil, apply an appropriately labeled pyrethroid pesticide. Dusts work best when applied to an area 6″ (15 cm) around the nest entrance. For structural nests, treat with dust or aerosol but do not seal the entrance. Structural nests should be either retreated with a long-lasting repellent material and sealed or the void opened up and cleaned out within 1-2 days to prevent future problems with dermestid beetles, spider beetles, and/or psocids.
What do Bumble Bees look like?
Introduction to Carpenter Bees
Carpenter bees get their common name from their habit of boring into wood to make galleries for the rearing of young. These are worldwide in distribution with 7 species occurring in the United States.
Recognition of Carpenter Bees
Adult body length about 1/2-1″ (12.5-25 mm); robust in form, resembling bumble bees, but with top surface of abdomen largely bare and shining. Hind tibiae with apical spurs. Front wing 2nd submarginal cell triangular; hind wing with a small jugal lobe (lobe on rear margin near body).
Similar Groups to Carpenter Bees
(1) Bumble bees (Apidae) have hairy abdomen with yellow markings, 2nd submarginal cell somewhat rectangular to pentagonal, and hind wings lack a jugal lobe.
(2) Some robber flies (Diptera: Asilidae) which resemble bumble bees, with only 1 pair of wings.
(3) Some hawk moths (Lepidoptera: Sphingidae) which resemble bumble bees, with siphoning mouthparts.
Representative Species of Carpenter Bees
- The eastern carpenter bee, X. virginica (Linnaeus), is the most common eastern species and its range extends westward to Kansas and Texas. It is about 1″ (25 mm) long and closely resembles the bumble bee except that the abdomen is black and shiny (with only a dorsal transverse hairy yellow band near its base). The male has a yellow face, whereas, the female’s is black.
- The California carpenter bee, X. californica Cresson, is found in the north Coast Ranges and the Sierra Nevada of California and in Oregon’s Cascade Mountains. This bee is 3/4-1″ (20-25 mm) long and both sexes can be mostly metallic green or blue with grayish/dusky wings. The male’s pronotum has orange, yellow, or white hairs and its 1st abdominal segment has whitish hairs.
- The valley carpenter bee, X. varipuncta Patton, is found primarily in the valleys and lower foothills of California and Arizona. This species is about 3/4″ (18-20 mm) long. The female is shiny black with brilliant metallic purple, brassy, or bronzy reflections, in stark contrast to the golden brown or buff color of the male. The female’s wings are somewhat smokey.
- The mountain carpenter bee, X. tabaniformis Smith, is found mostly in the foothills and mountains of Arizona, California, Nevada, and Oregon. This bee is about 1/2-5/8″ (12-17 mm) long and both sexes are black. The male’s head has yellow and white hairs mixed with black hairs.
Biology of Carpenter Bees
Carpenter bees are not social insects and do not live in nests or colonies. The adults over winter, typically in abandoned nest tunnels. In the spring, the survivors emerge and feed on nectar. Then mating begins and extends into nest-construction time. The mated female may either reuse an old gallery, construct a new one by lengthening an old gallery, bore an entirely new one, or extend a gallery from a common entrance hole. The female typically bores a circular hole (same diameter as her body) straight into the wood across the wood grain for a distance equal to her body length. Then the gallery takes a right-angle turn, usually with the grain of the wood and parallel to the outer longitudinal surfaces. New galleries average 4-6″ (10-15 cm) long but galleries developed/used by several bees may extend up to 10 feet (3 m). Additional galleries may be excavated above/below earlier galleries resulting in 2 or 3 tiers/levels of galleries.
The female provisions each gallery cell starting at the closed end of the gallery with a mass of pollen and regurgitated nectar upon which she lays a single egg. This portion of the gallery is then sealed off with a chewed wood-pulp plug, making a chamber or cell. This process is repeated until a linear series of 5-6 cells is completed, about 1 cell per day. Developmental time (egg to adult) for the carpenter bee (X. virginica) is about 36 days and for the mountain carpenter bee (X. tabaniformis), it is about 84-99 days.
Habits of Carpenter Bees
Females of the carpenter bee (X. virginica) will nest in a wide range of woods, but prefer weathered and unpainted wood. Valley carpenter bees prefer partially decayed live oak, deciduous oak, eucalyptus, and other hardwoods. The California carpenter bee nests in incense cedar and redwoods. The Mountain carpenter bee is recorded as nesting in structural timbers.
Male carpenter bees tend to be territorial and often become aggressive when humans approach, sometimes hovering a short distance in front of the face or buzzing one’s head. Since males have no stinger, these actions are merely show. However, the female does have a potent sting which is rarely used.
Control of Carpenter Bees
Carpenter bee control consists of treating each individual gallery with an appropriately labeled pesticide. Dusts, wettable powders, microencapsulated, and aerosol residual formulations work best. Aerosol injection systems are probably the most efficient and safest way to treat galleries, especially when on a ladder. Do not seal the treated gallery for 24-48 hours so that the female has time to be exposed to a lethal dose. Following successful treatment, seal the entry holes with wood filler or 3/8″ (10 mm) wood dowel plugs to discourage reuse of existing galleries in the future. Newly matured bees should contact a lethal dose before they can emerge. Also, abandoned carpenter bee galleries may be adopted by the mason wasp, Monobia quadridens (Linnaeus), and by the giant resin bee, Megachile sculpturalis Smith, where these species occur.
Carpenter bees rarely attack painted wood. They can be discouraged from using wood by applying an appropriately labeled repellent material such as one of the pyrethroids, and microencapsulated or wettable powder formulations are best.
What do Carpenter Bees look like?
Introduction to Honey Bees
Honey bees get their common name from the sweet yellowish to brownish fluid they make from the nectar of flowers and use as food. Honey bees not only provide honey and wax, but as pollinators are of far greater importance. They are also responsible for a large share of insect stings, although many stings blamed on “bees” are actually done by yellowjackets. Honey bees are worldwide in distribution.
The 2 most commonly encountered kinds/strains of honey bees in the United States are the common and rather docile European honey bee (EHB) and the much more aggressive Africianized honey bee (AHB). The EHB is found throughout most of the United States. The AHB invaded the United States from Mexico in 1990, and by 1/2007 was established in southern California, southern Nevada, Arizona, New Mexico, Texas, Oklahoma, western Louisiana, southern Arkansas, and central and southern Florida.
Recognition of Honey Bees
Adult worker’s body length about 1/2-5/8″ (11-15 mm). Color usually orangish brown to sometimes black, gaster (enlarged rear portion of abdomen) broadly banded with orange and brown or brown and black; with body mostly covered with branched, pale hairs, most dense on thorax. Eyes hairy. First segment of hind tarsus enlarged, flattened. In addition, hind tibiae lack apical spurs; front wing venation with marginal cell narrow, parallel-sided, and 3rd submarginal cell oblique; hind wings with jugal lobe (lobe on rear margin near body). Barbed stinger present.
Queens slightly larger, about 5/8-3/4″ (15-20 mm) long, pointed abdomen extends well beyond wing tips, with smooth stinger. Males or drones robust, about 5/8″ (15-17 mm) long, stinger absent.
Africanized honey bees look just like our “domestic” bees except for being slightly smaller. A specialist is required to identify specimens by genetics or measurements.
Similar Groups to Honey Bees
(1) Yellowjackets (Vespidae) have abdomen usually banded with yellow and black, hind tarsal 1st segment not enlarged, hind wing lacks a jugal lobe (lobe on rear margin near body).
(2) Other bees (various families) lack hairy eyes, have apical spurs on hind tibiae, lack having front wing’s marginal cell narrow and parallel-sided and 3rd submarginal cell oblique.
(3) Some syrphid flies (Diptera: Syrphidae) which resemble honey bees, with 1 pair of wings.
Biology of Honey Bees
Honey bees are social insects and live as colonies in hives, with mature colonies of 20,000-80,000 individuals. Adults are represented by workers which are infertile females, a queen or inseminated female, and drones (males) which come from unfertilized eggs.
The entire population overwinters. There is only one egg-laying queen in the hive and she mates only once. She can lay as many as 1,500 to 2,000 eggs per day, and may live as long as 5 years. The queen produces many pheromones, mostly from her mandibular glands, which regulate among other things the production of new queens and inhibit development of worker ovaries. The young workers care for the young or brood, build the comb, provide hive ventilation, and guard the hive entrance. Older workers serve as foragers to gather pollen, nectar, and propolis or bee glue. Workers live only about 5 to 7 weeks during the summer but those emerging in the autumn, over winter. Drones (males) appear periodically and are short lived, usually living only a few weeks.
Honey bees swarm primarily when the colony size gets too large for the available hive space or the queen begins to wane or fail. New queens are produced and the old queen leaves with a large number of workers. Our common European honey bee colony usually swarms only once each 12 months. Africianized honey bees swarm as often as once every 6 weeks and can produce 2 swarms each time.
Habits of Honey Bees
Honey bees are not aggressive, and do not search for something to attack. Instead, they are defensive and will attack only whatever seems to threaten the colony.
Swarms first move to a temporary site such as a tree branch. The swarm will usually remain here for about 24-48 hours until permanent quarters are located, and then moves on. Permanent quarters may consist of a bee hive, hollow tree, hollow wall, attic, etc., typically some place which is sheltered from the weather.
Bees in a swarm are very docile and not likely to sting because they harbor no food stores or young and therefore, have nothing to defend. Likewise, honey bees encountered away from the hive are unlikely to sting unless severely provoked, like stepping on them. However, if the hive entrance is approached, the guard bees can become very aggressive; do not approach hives without proper protection. Worker bees have barbed stingers and when used, the stinger, poison sac, and associated tissue are torn from the body. If the stinger is not removed immediately, muscle contractions will drive the stinger deeper and deeper into the skin and there is greater time for toxin injection. In addition, the stinger gives off a pheromone which attracts other bees and induces an alarm and attack behavior. Therefore, immediate removal with a fingernail or knife blade is recommended; squeezing only forces more venom in. The AHB will pursue the intruder/victim for up to 328 ft (100 m) whereas, the EHB will pursue for only about 33 ft (10 m).
The normal reaction to bee stings is local pain for a few minutes followed by swelling at the sting site which subsides in a few hours. Often itching and heat may last for a few hours. First-aid consists of quickly removing the stinger with a fingernail or knife blade. After stinger removal, do not rub the area because this causes the venom to spread, or scratch the area which may cause secondary infection, but clean it with soap and water followed by an antiseptic. A cold compress will reduce pain and swelling. A topical application of household ammonia cleaner will diminish the pain as well. If one has been stung more than 15 times, or is feeling ill, or if the reaction is more severe than a small welt, consult a physician immediately because death can occur within 15-30 minutes from severe allergic reactions. The USDA/ARS says that the average person can safely tolerate 10 stings per pound of body weight, which means that although 500 stings can kill a child, the average adult could withstand more than 1100 stings.
Africanized honey bees are much more aggressive than the EHB and are extremely protective of their hive and brood (young). Their colonies are smaller and they use a much wider range of nesting sites. Nesting sites include water meter boxes, utility poles, cement blocks, junk piles, the eave area of houses, abandoned structures, tree limbs, and holes in the ground. Potential sites include mail boxes, overturned flower pots, old tires, mobile home skirts, etc.
Control of Honey Bees
If you live in an area known to have AHB or are within 100 miles of such an area (they are advancing at a rate of up to 100 miles each year), it is not advisable to approach a colony, hive, or swarm of honey bees without first putting on a complete bee suit. Likewise, it is not advisable to get within 100 feet (30 m) of an AHB colony, hive, or swarm unless fully suited up. Schools and day-care facilities should conduct daily surveillance, have an action plan in place, and educate their students and faculty.
Anyone attacked should run quickly until they reach shelter such as a vehicle or building, and then the stingers can be removed. If someone else is observed being attacked, advise them to run to shelter, but don’t go to assist unless properly suited-up because you will also be attacked. Call 911 for rescue help.
Rescue personnel typically use a 1% solution of liquid dishwashing liquid to water (1/2 to 1 cup detergent/gallon of water), which will immediately immobilize honey bees and kill the bees within 60 seconds. Firefighters can accomplish the same results by using water plus a non-toxic wetting agent.
For EHB swarmers in the yard, contact the cooperative extension service or call a local beekeeper or apiculture supply shop for beekeepers interested in removing swarms. These same contacts are worth a try for live removal from walls and attics.
Live removal of EHB is desirable and the preferred method in the case of brick wall construction (more difficult to open up), but it is often impossible to locate anyone willing to do this. Live removal involves trapping the bees out and capturing them with a decoy hive containing a queen and a few bees, killing the queen and the few remaining bees with pyrethrins or resmethrin, and after several days allowing the bees back in to remove the honey. Next, the nest void should be treated with a long-lasting repellent dust to discourage wax moths, dermestid beetles, etc., and then immediately sealed. This whole process may take 3-6 weeks.
If honey bees must be killed in a wall or attic, pesticide application should be made at night using only background light; a bee veil should be worn. Appropriately labeled aerosol pyrethroids are most convenient and effective, with dusts being second choice.
For walls, first locate the entrance/exit(s) being used. Next, the colony’s nest should be located because the nest can be far enough away from the entrance that entryway-applied insecticides will not reach the bees. The nest can best be located at night by tapping on the walls in the area of buzzing and listening for the loudest sound. Also, honey bees keep the center of their nest at about 95°F (35°C) which will warm the wall enough such that it can often be detected with one’s hand.
For walls, first seal any possible entrances to living quarters such as window sashes. Then the insecticide application can be made either directly through the entrance hole or by drilling a small hole (3/32-1/8″ or 2-3mm) through the inside wall, the latter being necessary for nests located some distance from the entrance hole. Seal the application hole immediately after insecticide introduction. For attics, direct application is required.
The next day the dead bees, comb, and honey must be removed or else as the wax deteriorates, there will be a strong honey and dead bee odor, the honey will often seep through the plaster walls, and/or this debris will attract other insects and mice. In the case of a wall, the wall must be opened up. It is suggested that the potential customer be notified in writing of their responsibility in this matter before any contract is signed.
In the residential situation, it may be desirable to discourage foraging bees from coming around the home. This is especially true if small children or allergic people are present. Discouragement consists of the removal or preventing access to any sugar, food, or water which may attract them, such as soda cans, flowers, water dishes, etc. Recommend that flowering vegetation be located away from doorways, decks, sidewalks, mailboxes, and other areas frequented by people. Also, lawns should be kept free of white clover and flowering weeds.
What do Honey Bees look like?
Introduction to Solitary Ground/Cavity Nesting Bees
The common name comes from the fact that these are solitary and not social bees, and that they usually nest in the ground while some use natural cavities. These solitary bees can become urban nuisance pests when they nest in large numbers near structures, and they can sting. They are found throughout the United States. This discussion will be restricted to those species of these 3 families which nest in the ground.
Recognition of Solitary Ground/Cavity Nesting Bees
All 3 families composed of small to medium-sized bees with females and males about 1/8-3/4″ (4-20 mm) long; females usually 1-2 mm longer than males of same species. Color usually dark, some metallic, some with pale bands. Front wing with 2 or 3 submarginal cells. Hind wing with jugal lobe (lobe on rear margin near body) longer than submedial cell. Additionally –
Andrenidae. Head with 2 subantennal sutures (impressed lines) below each antennal socket; glossa (tongue middle structure) short, pointed. Front wing with basal vein straight or nearly so. Color usually dark brown to black, some species with abdomen banded with pale hair and/or pale hair on body.
Colletidae. Head with 1 subantennal suture (impressed line) below each antennal socket; glossa (tongue middle structure) short, bilobed or truncate. Front wing with basal vein straight or nearly so. Color brownish with abdomen banded with pale hairs, or black and relatively bare with yellowish/whitish areas on face.
Halictidae. Head with 1 subantennal suture (impressed line) below each antennal socket; glossa (tongue middle structure) short, pointed. Front wing with basal vein strongly arched. Color of some species partly or entirely metallic green, blue, brazen, or cuperous.
Similar Groups to Solitary Ground/Cavity Nesting Bees
(1) Digger bees (Anthophoridae, subfamily Anthophorinae) have front wing with 2nd submarginal cell shorter than 1st, hind wing with jugal lobe (lobe on rear margin near body) shorter than submedian cell, and robust and hairy.
(2) Cuckoo bees (Anthophoridae, subfamily Nomadinae) have hind wing with jugal lobe very small and rounded, and often with whitish/yellowish markings.
(3) Leafcutting bees (Megachilidae) have front wing with 2 almost equal-sized submarginal cells, hind wing with jugal lobe shorter than median cell, pollen carried on underside of abdomen.
(4) Honey bee (Apis mellifera) with hairy eyes, hind tibia lacks apical spurs, and usually orange brown.
Biology of Solitary Ground/Cavity Nesting Bees
These are solitary bees which do not live in colonies. Adults are queens or males. Andrenid bee burrows are made in the ground, usually consisting of a long vertical tunnel with lateral branches off of this tunnel to each cell. Sometimes large numbers of these bees will nest close together, particularly in bare-ground areas. They provision each cell with pollen and nectar. Both sexes over winter in the nests.
Colletid bees nest in various natural cavities or in the ground. Their burrow often consists of a straight tunnel with several short branches at its end containing multiple cells. Cells are provisioned with a mixture of pollen and nectar.
Halictid bees resemble andrenids in nesting habits. Sometimes large numbers nest close together, often sharing the same tunnel to the outside. Developmental time (egg to adult) can be about 2 weeks. Sweat bees (genus Halictus) are sometimes a nuisance when they are attracted to perspiration as a moisture source. They can give a mild sting, especially when being brushed away.
Habits of Solitary Ground/Cavity Nesting Bees
Andrenid and halictid bees have a habit of nesting in large numbers in the limited bare areas found around the foundation or in the yard.
Some members of the halictid bee genera Halictus and Lasioglossum are called sweat bees because they are attracted to perspiring skin. Although they are usually just a nuisance, they can give a sharp mild sting especially when being brushed away.
All of these bees visit various flowers for both pollen and nectar. Some species are very important pollinators of agricultural crops, such as the alkali bee (Nomia melanderi; Halictidae) on alfalfa in the Pacific Northwest.
Control of Solitary Ground/Cavity Nesting Bees
These are beneficial insects and control should be avoided if possible. However if control is necessary, dusting the bare nesting area with an appropriately labeled pesticide is effective. Pyrethroids and some carbamates are particularly effective.
The customer should be advised to eliminate all bare-ground areas as a long-term solution to discourage these bees.
What do Solitary Ground/Cavity Nesting Bees look like?
Introduction to Paper Wasps
Paper wasps get their common name from the paperlike material of which they construct their nests; true also of the other vespids. It has been suggested that they be called umbrella wasps based on the shape of their nests. In the urban situation, these usually unaggressive wasps are a nuisance pest. Various species are found throughout the United States.
Recognition of Paper Wasps
Adults about 5/8-3/4″ (16-20 mm) long. Color brownish with yellow markings, a few species with reddish markings. Head with clypeus (upper lip) usually pointed at apex. Pronotum in lateral view almost triangular, extending to tegulae (structure at base of front wing) or nearly so. Long-legged, middle tibia with 2 apical spurs. Hind wing with small jugal lobe (lobe on rear near body). 1st abdominal segment conical, not stalklike.
Similar Groups to Paper Wasps
(1) Yellowjackets and hornets (subfamily Vespinae) with clypeus (upper lip) broadly truncate and slightly notched at apex, hind wing lacks jugal lobe (lobe on rear near body).
(2) Potter and mason wasps (subfamily Eumeninae) have middle tibia with 1 apical spur.
(3) Spider wasps (Pompilidae) have mesopleura (side of mesothorax) with a transverse suture (impressed line), hind wing with a jugal lobe.
(4) Longwaisted paper wasps, Mischocyttarus spp. (formerly in subfamily Polybiinae, now Polistinae) with 1st abdominal (=gaster) segment long, slender, and stalklike, much longer than in Polistes spp.
Representative Species of Paper Wasps
- Northern paper wasps, Polistes fuscatus (Fabricius). Length about 3/4″ (20 mm); color forms, northern form dark, primarily brown and black with paler markings, antenna not tipped with yellow, with pale brown to yellow paired longitudinal stripes on rear of thorax (propodium), southern form pale, body marked and banded with 2 yellow longitudinal stripes on propodium, with paired orange-brown oval patches on top side of 2nd gastral (“abdominal”) segment; widespread in North America.
- Annularis paper wasp, Polistesannularis(Linnaeus). Length about 1″ (25 mm); blackish brown with bright yellow margin on 1st abdominal segment; found in Connecticut, New York, New Jersey, Maryland, Delaware, southeastern U.S., Texas, and South Dakota.
- Apache paper wasp, Polistes apachus Saussure. Length about 3/4″ (20 mm); golden brown with yellow markings, pronotum bordered with thin yellow stripe, mesonotum with 2 transverse stripes (anterior narrow, posterior broad), abdomen with alternating stripes of golden brown and yellow; found in southern California and in Texas and adjacent regions.
- Dominulus paper wasp, Polistes dominulus (Christ). Length about 5/8-3/4″ (15-20 mm), color pale, body marked and banded with black and yellow, top of 2nd gastral (“abdominal”) segment with paired yellow spots; found in northeastern, mid-Atlantic, and mid-western states, but expanding its range through contentinal United States.
- Dorsalis paper wasp, Polistes dorsalis dorsalis (Fabricius). Length about 3/4″ (17-18 mm); reddish brown with 1st abdominal segment narrowly outlined with yellow, tarsi yellow; found in southeastern United States, Missouri, Kansas, Colorado, Oklahoma, Texas, and New Mexico.
- Golden paper wasp, Polistes fuscatus aurifer Saussure. Length about 5/8-3/4″ (16-20 mm); black with face and most of abdomen bright yellow; thorax with 6 narrow yellow stripes, legs mostly yellow; found in British Columbia, Washington, Oregon, California, Nevada, Idaho, and Montana.
Biology of Paper Wasps
Paper wasps are semi-social, existing in small colonies but without a worker caste. Overwintering inseminated queens begin building nests in the spring. These founding queens are often joined by other inseminated queens which assist in nest building and maintenance. Such secondary queens become functional workers and relegate egg laying to the founding queen. However, should the founding/dominant queen die, one of the secondaries can assume egg laying and assure that the nest will survive.
Nests consist of a single layer of paperlike comb with the cells opening downward. This comb is supported/suspended from a branch, twig, or horizontal surface by a single long pedicel; this single, long pedicel apparently aids in the defense of the nest by predators such as ants. This comb is never enclosed by an envelope, but remains naked. A single egg is laid in each cell and the developing larva is fed primarily protein from insect prey through the open cell. The cell is capped when the larva is ready to pupate. Nests are small to moderate in size, containing up to about 150-250 cells; largest contained 320 cells and was 6×8″ (15×20 cm) in size.
Typically, nest are not reused the following season. However, the dominulus paper wasp, P. dominulus, will reuse old nests. In so doing, the nests can become quite large in size for a paper wasp.
Habits of Paper Wasps
Paper wasps hang their comb nests from twigs and branches of trees and shrubs which can cause concern when ornamental shrubs and hedges are trimmed or fruit is being picked from trees. If a nest is contacted, there is high probability that person doing the trimming or fruit picking will get stung. Paper wasps also like to hang their comb nests from porch ceilings, the top member of window and door frames, soffits, eaves, attic rafters, deck floor joists and railings, etc., almost any protected place imaginable including under roof shakes.
In the autumn, inseminated females seek places to over winter. They will investigate crevices and penetrations associated with vents and skylight flashing, chimneys, window and door frames, utility-line penetrations, etc. until they find a suitable place. Overwintering wasps may find their way into living spaces on sunny autumn, winter, and/or spring days, especially if there are cathedral ceilings present. Since these are inseminated females and not daughters defending a nest, they are not aggressive and stinging rarely occurs.
Control of Paper Wasps
Paper wasps are beneficial insects, helping to control many insect pests. If their nest is located near human activity, control is warranted. It is essential that the adults be contacted and killed or they will quickly rebuild. For adults, use an appropriately labeled pesticide such as aerosol pyrethrins or a pyrethroid and do the application early in the morning or at night when most of the wasps will be on the nest. Then remove the nest. The continual removal of nests from the structure over the summer will greatly reduce the likelihood of paper wasps being around to enter in the autumn to over winter.
Before trimming shrubs or hedges or picking fruit, check the plant for paper wasp nests and treat and remove any found before proceeding. Be careful that the pesticide used will not harm the plant involved.
When paper wasps gather cellulose for nest expansion from wood fences and deck railings, customers may get anxious. Consider treating these surfaces with an insecticidal soap or a repellent essential-oil formulation. It may be necessary to reapply following a rain.
What do Paper Wasps look like?
Introduction to Mud Daubers
This group of wasps gets its common name from the fact that they construct their nest of mud. They are typically nuisance pests. Mud daubers are found throughout the United States.
Recognition of Mud Daubers
Adults mostly about 1/2-1+” (12-25+ mm) long, slender. Color usually black, may have pale markings or a metallic luster. Thorax with pronotum collarlike. Wings clear or dark; front wing with 1 or 3 submarginal cells. Abdomen either very slender or petiolate (stalked).
Similar Groups to Mud Daubers
(1) Other sphecid wasps (Sphecidae) do not make mud nests and either with more than 1 submarginal cell in front wing and eyes not notched on inner margin or 1 tooth on front tarsal claws, middle tibia with 1 apical spur, and usually both recurrent veins meet 2nd submarginal cell of front wing.
(2) Paper (Polistes spp.) and some potter wasps (Eumenes spp.) with pronotum in lateral view almost triangular, extending to tegulae (structure at base of front wing) or nearly so, 3 submarginal cells in front wing, and 1st abdominal segment conical, not stalklike.
Representative Species of Mud Daubers
- Organpipe mud daubers; subfamily Trypoxyloninae. Mostly about 1/2″ (13 mm) long; color black; head with inner margins of eyes notched; front wing with 1 submarginal cell, marginal cell pointed apically; and make long (up to 8+”/20+ cm) tubular mud nests provisioned with spiders.
- Black-and-yellow mud dauber, Sceliphron caementarium (Drury); subfamily Sphecinae. About 1/2-1 1/8″ (14-28 mm) long; color dull black with antennal bases, prothoracic collar, scutellum, portion of metathorax, petiole, and parts of legs bright yellow; 1 tooth on front tarsal claws, middle tibia with 2 apical spurs; front wing with 3 submarginal cells, both recurrent veins meet 2nd submarginal cell; abdomen stalked at base, petiole long; and nests are comprised of several short tubular mud cells clustered side-by-side and plastered over with mud, which are provisioned with spiders.
- Blue mud dauber, Chalybion californicum (Saussure); subfamily Sphecinae. About 1/2-3/4″ (12-18 mm) long; color metallic blue, blue-green, or blackish with bluish wings; 1 tooth on front tarsal claws, middle tibia with 2 apical spurs; front wing with 3 submarginal cells, both recurrent veins meet 2nd submarginal cell; abdomen stalked at base, petiole moderate in length; and does not make a nest of its own but instead is dependent on those of black-and-yellow mud dauber (S. caementarium), discarding the original nest contents, then adding its own spiders and eggs.
Biology of Mud Daubers
Mud daubers are solitary wasps, they are not social and do not live in colonies. The Sphecinae mud daubers over winter as full-grown larvae, pupate in the spring, and emerge shortly thereafter. Females construct nests of mud. Many short mud tubes/cells, usually about 1″ (25 mm) long, are constructed side-by-side. Each cell is provisioned with several spiders which she has paralyzed with her venom, with the first spider in having an egg deposited on it. Eventually this mass of tubes is about 3-4″ (7.6- 10 cm) in diameter and is entirely plastered over with mud. The female then selects another site and starts over. A larva can complete its development in about 3 weeks, then spins a silken cocoon but does not pupate until the following spring. Females typically provision their cells with only one kind or group of spiders.
Mud daubers do not defend their nests, and only rarely sting.
Habits of Mud Daubers
Mud daubers typically select a sheltered site to build their mud tubes. Favorite sites include under eaves, porch ceilings, in garages and sheds left open, in barns, protected building walls, in attics, etc.
Nests typically exhibit round holes in them as the wasps emerge. This means the nest is probably old and inactive after springtime.
Control of Mud Daubers
Mud daubers are beneficial insects and help control spiders. If the nest is located near human activity, then control is warranted. First, if the female is in the tube, simply wait a few minutes for her to leave, or treat her with a short burst of an appropriately labeled aerosol pyrethrin/pyrethroid pesticide; use of a water-based pesticide formulation will create a muddy mess. Since mud daubers are reluctant to sting and do not aggressively defend their nests, their mud nests can simply be removed with a putty knife or scraper; sweep up the dislodged mud nest. Any mud tube nests should be removed because they may be parasitized by cuckoo wasps (family Chrysididae) during construction, or abandoned nests may be adopted and rehabbed by leafcutting bees (family Megachilidae). Activity can be dis-couraged in a given area by the application of a microencapsulated or wettable powder pyrethroid formulation.
What do Mud Daubers look like?
Introduction to Yellowjackets
Yellowjackets receive their common name from their typical black and yellow color pattern. They are worldwide in distribution with about 16 species occurring in the United States.
Recognition of Yellowjackets
Adult workers about 3/8-5/8″ (10-16 mm) long depending on the species, with their respective queens about 25% longer. Abdomen usually banded with yellow and black, several species with white and black, and 2 northern species also marked with red. Wings folded longitudinally at rest. In addition, pronotum in lateral view almost triangular, extending to tegula (structure at base of front wing) or nearly so; front wing 1st discoidal cell about half wing length; hind wing lacks jugal lobe (lobe on rear margin near body); clypeus (front lip) broadly truncate and slightly notched; middle tibiae with 2 apical spurs. The worker abdominal color pattern is usually distinctive for each species but because it does vary, a series of specimens may be required for identification.
Similar Groups to Yellowjackets
(1) Baldfaced hornets (D. maculata) mostly black with yellowish-white markings on face, thorax, and end of abdomen.
(2) European hornets (Vespa crabro) very large (up to 1 3/8″/35 mm long), brownish with orange stripes.
(3) Honey bees (Apidae) with hairy eyes, hind tarsal 1st segment enlarged and flattened, hind wing with jugal lobe (lobe on rear margin near body), abdomen not banded with yellow and black.
(4) Some clear-wing moths (Lepidoptera: Sesiidae) which resemble yellowjackets, with siphoning mouthparts.
Representative Species of Yellowjackets
- The common yellowjacket, Vespula vulgaris (Linnaeus), is found throughout most of the United States.
- The eastern yellowjacket, V. maculifrons (Buysson), is common east of the Great Plains.
- The German yellowjacket, V. germanica (Fabricius), occurs throughout most of the United States except in the far south.
- The southern yellowjacket, V. squamosa (Drury), is the most common southern species but its range extends northward to the Great Lakes and westward to central Texas.
- The western yellowjacket V. pensylvanica (Saussure), is the most common and pestiferous in California and occurs primarily west of the Great Plains.
- The aerial yellowjacket, Dolichovespula arenaria (Fabricius), is distributed throughout most of the United States.
Biology of Yellowjackets
Yellowjackets are social insects and live in nests or colonies. The adults are represented by workers that are sterile females, queens, and males which come from unfertilized eggs and usually appear in late summer.
Typically, only inseminated queens over winter and do so in sheltered places. In the spring, she uses chewed-up cellulose material to construct a golf ball-sized paper carton nest of a few cells which will eventually consist of 30 to 55 cells covered by a paper envelope. One egg is laid in each cell and the queen feeds the developing larvae arthropod protein material and nectar. After about 30 days, the first 5 to 7 workers emerge and shortly thereafter take over all the work except egg laying. The nest will eventually consist of a number of rounded paper combs which are open ventrally and attached one below another, and are usually covered with a many-layered paper envelope. Nest size varies from 300 to 120,000 cells, averaging 2,000 to 6,000 cells, and usually contains 1,000 to 4,000 workers at its peak. Later in the season, larger reproductive cells are built in which queens will be reared; males are usually reared in old worker cells. The colony is then entering the declining phase. The newly emerged queens and males leave the nest and mate. Only the inseminated females hibernate and survive the winter. The founding queen, the workers, and the males all die.
However, in the south and southwest, some species (V. germanica, V. squamosa, and
V. vulgaris) are known to maintain large perennial colonies. Such colonies often have multiple queens, tens of thousands of workers, and contain several million cells.
Habits of Yellowjackets
Depending on the species, the overwintered queen will usually select either a subterranean or aerial nesting site. Most of the pest species are ground nesting where their soccer ball to basket ball-sized paper nests are usually suspended from overlying plant roots, logs, or landscape timbers. The German yellowjacket usually nests in large (6- 12 cu ft/0.17-0.34 cu m) structural voids in buildings in the United States and the western yellowjacket occasionally nests in buildings. The aerial yellowjacket commonly attaches its nest to shrubs, bushes, houses, garages, sheds, etc.
Those nesting in the ground typically select areas bare of vegetation or else clear an area around the entrance. There are nest entrance guards to protect the colony. Yellowjackets are very slow to sting unless the nest entrance is approached and then they are quite aggressive. Each can sting a number of times, inflicting much pain. Some people become hypersensitive to their stings and future stings can become life threatening. Those nesting in or on buildings are only a problem when the nest or nest entrance is located near human activity. Overwintering queens may enter the living space during the winter seeking warmth, or in the spring when they are looking for a nest site or just trying to get back outside.
Control of Yellowjackets
Yellowjackets are considered beneficial insects because their food consists mostly of various arthropods, often pest species. However, if their nest is located close to occupied buildings, recreational areas, or within structures, then control is warranted. Customers should be advised prior to scheduling the service that closure of active yellowjacket nest entry holes with caulk or sealants will complicate the treatment process. They should also be advised that doing so will increase the risk of driving alarmed yellowjackets into the occupied areas of the building.
During the day, locate where the nest entrance(s) is/are for each colony to be controlled; be careful, nests in voids or cavities may have more than one entrance. Control should be done at night when most of the yellowjackets are in the nest. If possible, it is best to make the application using a beepole or an extension-handle duster. Only background lighting should be used and a bee veil should be worn.
If it is a ground nest, then dust an area for 6″ (15 cm) around the entrance hole and/or puff dust into the entrance hole. Apply an appropriately labeled pesticide dust.
If the nest is located in a wall void, then either dust the void via the entrance hole or apply an appropriately labeled aerosol pyrethroid and close the entrance hole. In a day or so, the wall void nest area should be opened up and cleaned out to prevent future dermestid beetle, spider beetle, and/or psocid problems. If the wall void is not to be opened up and cleaned out, then in a day or two, treat the wall void with a long-lasting, highly repellent material and/or boric acid dust. The customer should be advised that this will not prevent future pest problems associated with the dead yellowjackets and their nest in the wall.
Yellowjacket nests in buildings occupied by chemically sensitive people can be treated by fastening a PVC or cardboard extension tube to the exterior sheathing around the entrance hole. Before attachment, the interior surface exclusively should be treated with a nonrepellent pesticide formulation (dust, WP, ME, or SC). Additional interior coatings of the tube with pesticide may be necessary. This treatment should be done at night and while wearing proper protective equipment.
If it is an aerial nest, then an appropriately labeled aerosol works well. If possible, it is much safer to make the application from the ground using a beepole. If the application must be made during the daytime when many of the foragers will not be present, then dust is the choice because foragers will contact it upon their return. In situations where pesticide application is not desirable, the use of baited traps can help reduce the number of adults. For German and eastern yellowjackets, grenadine has been found to be a very attractive bait. The traps should be placed 3-8 ft (1.8-2.4 m) above the ground, between the area to be protected and the nesting area, such that they are protected from passers by and the wind, and placed about 5 ft (1.5 m) apart at the height of the season. They should be checked daily, and cleaned and rebaited as required.
What do Yellowjackets look like?
Special thanks to the National Pest Management Association Field Guide Pro for the information found on this page.
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