bullseye.pngPest Library – Common Pests

 American Cockroach

AmerianCockroach.jpgAmerican cockroaches, also known as water­bugs or palmetto bugs, are more common in com­mercial buildings and are one of the most common cockroaches in sewer systems. The largest cock­roach in Texas, it can grow 1½ to 2 inches long. Both the adult male and the female can fly.

Adults are reddish brown, with tan to light-yellow bands outlining the pronotum. Young nymphs are grayish brown, but after the first few molts, they become more reddish brown.  American cockroaches are long-lived, reaching adulthood and sexual maturity in an average of 600 days. As adults, they usually live 1 to 2 years.

Ear Wigs

Earwig.jpgEarwigs range from ¼ to 1¼ inches (5 to 31 mm) long and are flattened from top to bottom. Their color ranges from brown to black; some species have yellow or buff-colored stripes or a reddish color­ing on the head, body, and legs. All earwigs have a pair of hardened forceps that protrude backward from the tip of the abdomen.

Used for defense, the appendages vary among species and from male to female. The adult earwig has a short, leathery pair of wings. A second pair of membranous wings may be folded underneath the first pair. Earwigs have chewing mouthparts, which they use to catch and eat insects. Earwigs feed at night, and their diet is highly variable. Most earwig species prey on other insects—dead and living—and supplement their diet with decaying organic matter. They may also feed on algae, fungi, lichens, and mosses. Indoors, they may feed on houseplants or sweet, oily, or greasy foods.


centipede.jpgCentipedes have flattened bodies that can be brown, gray, red, or greenish blue. They have one pair of legs per body segment. The first pair of legs have been modified to function as claws used to capture prey. Centipedes live for 1 to 6 years. They prefer moist, protected habitats such as under bark, stones, leaves, or rotted logs. They spend the winter as adults and lay eggs during the warmer months. The eggs are usually laid in soil and covered by a sticky substance.

A few species give birth to live young. Centipedes are predaceous; many species feed on other arthropods, such as insects.

Carpenter Ants

CarpenterAnt.jpgThere are 14 species of carpenter ants in Texas. The largest is the black carpenter ant (Camponotus pennsylvanicus), which is found primarily in wooded areas and rarely causes a problem indoors. Common indoor species are Camponotus rasilis and C. sayi. The workers of these species have dull red bodies with black abdomens. Worker ants are 1/4 to 1/2 inch long. They can be distinguished from most other large ant species because the top of the thorax is evenly convex and has no spines.

Also, the attachment between the thorax and abdomen has a single flattened segment. Although these ants can bite, they do not sting. Foraging worker ants leave the nest and seek foods such as insects, decaying fruit, and honeydew. When foraging worker ants enter a home they can be a nuisance. Occasionally carpenter ants, particularly C. rasilis, nest under stones or in other places, but they usually nest in dead wood, either outdoors in old stumps, dead parts of trees, firewood and fences, or indoors between wood shingles or in siding, beams, joists, fascia boards, etc.

Argentine Ants

ArgentineAnt.jpgArgentine ants ((Linepithema humile)) are an exotic species from South America. It is not as common in areas infested by the red imported fire ant.

Workers are light to dark brown and can be found both indoors and outdoors.

Their foraging trails may be as long as 200 feet.

Because each colony may contain several queens, the population of Argentine ants can be huge in some areas.

German Cockroaches

Germancockroach.jpgGerman cockroach adults are ½ to ⅝ inch long and are light brown with two dark stripes on the pronotum. Both males and females have wings extending to the end of their abdomens but they do not fly. Nymphs have wing pads and two dark stripes extending down the entire thorax and abdomen. German cockroaches are the most prolific of indoor cockroaches and can produce a generation in about 100 days.

They are one of the most wide­spread insect pests to public health in urban homes, apartments, and restaurants. They transport germs and are associated with allergies and asthma. German cockroaches do not live outdoors in Texas.

Fire Ants

FireAnt.jpgFire ants infest the eastern two-thirds of Texas. Worker ants are 1/16 to 3/16 inch long and are usually reddish or dark brown. Queen ants are larger (3/8 inch) and lose their wings after mating. This exotic species from South America prefers to nest outdoors in soil. The ants construct hills or mounds in open areas and also nest under rocks and landscape timbers, at the bases of tree trunks, in decaying wood and in clogged rain gutters.

Occasionally they are found indoors nesting in wall voids, decaying wood or utility housings. When a mound or nest is disturbed, the sterile female worker ants respond quickly and will run up vertical surfaces to attack the intruder. They bite and hold on to the victim with their jaws while injecting venom with stingers at the ends of their abdomens. Fire ant stings produce a burning sensation and often cause whitish blisters. Most people can tolerate the stings, but some people are very sensitive to fire ant venom and must seek medical attention.

Honey Bee

HoneyBee.jpgNesting bees produce wax honeycomb colonies or hives and are defensive when the developing bees being produced are disturbed or threatened. Avoid disturbing honey bee colonies nesting in the landscape, such as a hive in a drain pipe. Honey bees can nest in almost any cavity and sometimes even produce nests in the open. Be alert for the sound of worker bees flying in and out of openings in tree trunks or other potential nesting sites and notify others who may be at risk in those areas. When bees nest in wall voids, contact people experienced in bee removal.

Bees leave a scent where they nest, potentially attracting new colonies in the future. Thus, carpentry work will be required to remove the hive and prevent nests from reoccurring. The best way to avoid honey bee nests in the landscape is to remove or repair any potential nesting sites before honey bee swarms discover and colonize them.


Millipede.jpgMillipedes can live over 10 years. They lay eggs singly or in small groups in the soil. These arthropods prefer cool, moist environments such as mulch, leaf litter, or compost piles. Millipedes are not poisonous but have glands that produce a smelly fluid that can be irritating, especially if rubbed in the eyes. After handling millipedes, wash your hands with soap and water until the odor is completely gone.

Millipedes feed primarily on decaying organic matter; some eat other animals. Many millipedes may move into a home after heavy rainfall or during drought. However, they tend to die quickly because of lack of moisture and food.

Mole Cricket

MoleCricket.jpgMole crickets have front legs enlarged, shovel-like and modified for digging. Adults are cylindrical, nearly 1-1/2 inches long and dull brown. The shield-like segment just behind the head (pronotum) is marked with two pairs of pale spots. There are two finger-like projections (dactyls) on the terminal segment of the front leg (tibiae) separated by a u-shaped gap, and the hind tibiae is longer than the pronotum.

Adults have well-developed wings covering 3/4 of the abdomen when held at rest. They fly at night, can run quickly, but are poor jumpers. Nymphs resemble adults but are smaller and do not have fully developed wings.


Mosquito.jpgAll mosquitoes are classified in the order Diptera (true flies) and in the family Culicidae, which has more than 2,500 recognized species in the world. Adult mosquitoes are small, long-legged flies that have two wings like most other true flies.  All adult mosquitoes have three characteristics in combination, which separates them from all other flies:

1)     Long, many-segmented antennae.

2)     A piercing and sucking mouthpart system elongated into a distinctive beak or proboscis, at least in the females.

3)     Scales on the wing veins and margins.

To control the mosquitoes in your area, first you need to know what kinds are living there. At least 84 species of mosquitoes are known to occur in Texas. These species have considerable variation in their larval breeding sites, time of day when they bite, and flight distances of the adults.  Identification of larvae or adult mosquitoes to species is complicated and generally requires considerable expertise and training.

Paper Wasp

PaperWasps.jpgPaper wasps are one of the most common vespid wasps seen around homes and buildings. They are ¾ to 1 inch long and generally reddish-orange to dark brown. They often have yellow body markings. Paper wasps have three castes — infertile female workers, which make up most of the wasps on nests during the summer; males; and queens. Males and new queens are produced primarily in late summer and fall. Unlike yellowjackets and hornets, the paper wasp queen is not much larger than the worker wasps. Paper wasps build their nests from chewed wood fibers. The comb, which hangs from a single filament, is usually oriented downward and consists of a single tier of hexagonal shaped cells. Nests are most frequently seen under the eaves of houses but may also be found in attics, garages, storage sheds, barns, on shrubbery, trees and a variety of protected sites. The typical mature paper wasp nest contains 20 to 30 adults and rarely more than 200 cells.

Pill Bug

PillBugThe common pillbug, Armadillium vulgare, is a familiar inhabitant of mulched gardens and flower beds. Sometimes called “roly-polies” because of their habit of rolling up into a tight ball when disturbed, pillbugs are small (generally less than 1 cm-long), brownish to grey-black in color, and armored in appearance. The head and abdomen are relatively small, but the thorax is composed of seven overlapping plates. There are seven pairs of legs.

In most years pillbugs content themselves in feeding harmlessly on decaying vegetable matter in and on the soil. However when abundant–as in years of high rainfall–they can become a significant pest of landscape plants. Most feeding takes place in the evening or at night. Feeding pillbugs readily feed on small garden plants, and new transplants can be eaten to the ground overnight. Some of the plants attacked include hosta, pansies, blue lobelia, cardinal flower, English primrose, Allyssum, Dahlberg daisy, zinnia, verbena, and blackfoot daisy.