Pest Identification Library

Carpenter ants are large, black or dark-colored ants measuring 1/4 to 1/2 inch in length. Unlike termites, they don't eat wood but excavate it to create nesting galleries, leaving behind piles of sawdust-like material called frass. These destructive pests are one of the most common wood-damaging insects in North America.

Fire ants are small, aggressive red or reddish-brown ants measuring 1/8 to 1/4 inch long. They're known for their painful, burning stings that leave raised, white pustules on the skin. These invasive pests build distinctive dome-shaped mounds in lawns and open areas, with colonies containing up to 250,000 workers.

Sugar ants are small, dark brown to black ants measuring 1/16 to 1/8 inch in length. Often called odorous house ants, they emit a distinctive rotten coconut smell when crushed. These persistent pests are attracted to sweet substances and can quickly establish large colonies with multiple queens inside your home.

Pavement ants are small, dark brown to black ants measuring about 1/8 inch in length with distinctive parallel grooves on their heads and thorax. These common household pests get their name from their habit of nesting under pavement, concrete slabs, and along sidewalks. Colonies can contain thousands of workers and multiple queens.

House mice are small rodents with gray or light brown fur, large ears, small black eyes, and a slightly pointed nose. Adults measure 2.5 to 3.5 inches in body length with tails of similar length, weighing only 0.5 to 1 ounce. Despite their small size, mice are prolific breeders capable of producing 5-10 litters per year with 5-6 young per litter.

Norway rats are large, heavy-bodied rodents with brown or gray fur, small ears, small eyes, and a blunt nose. Adults measure 7-9 inches in body length with tails slightly shorter than their body, weighing 10-17 ounces. Also called brown rats or sewer rats, they're excellent swimmers and burrowers, creating extensive tunnel systems.

German cockroaches are small, light brown to tan insects measuring 1/2 to 5/8 inch long with two distinctive dark parallel stripes behind their heads. Despite having wings, they rarely fly and prefer to run. These prolific breeders are the most common cockroach species found in homes, restaurants, and food service establishments.

Silverfish are wingless, teardrop-shaped insects measuring 1/2 to 3/4 inch long with silvery-gray scales covering their bodies. They have three long tail-like appendages at the rear and two long antennae at the front. These primitive insects move in a distinctive fish-like wiggling motion and can live 2-8 years.

Earwigs are reddish-brown insects measuring 5/8 to 3/4 inch long with distinctive pincers (forceps) at the rear of their abdomen. Males have curved forceps while females have straight ones. Despite having wings folded under short wing covers, they rarely fly. The old wives' tale that they crawl into human ears is unfounded.

House crickets are light brown to tan insects measuring 3/4 to 7/8 inch long with three dark bands across their heads and long antennae. Males produce the distinctive chirping sound by rubbing their wings together to attract females. These nocturnal insects are strong jumpers and can become significant nuisance pests when they enter homes in large numbers.

House centipedes are distinctive yellowish-gray arthropods measuring 1 to 1.5 inches long with 15 pairs of very long, striped legs. Their legs become longer toward the rear, giving them a dramatic appearance. They move extremely quickly and can run up walls and across ceilings. Despite their alarming appearance, they're actually beneficial predators that hunt other household pests.

Paper wasps are slender, brownish insects with yellow or red markings measuring 5/8 to 3/4 inch long. They have noticeably long legs that dangle during flight. These social insects build distinctive umbrella-shaped paper nests with exposed cells, typically hanging from eaves, branches, or other protected overhangs. Unlike honeybees, wasps can sting multiple times.

Yellow jackets are robust, aggressive wasps measuring 3/8 to 5/8 inch long with distinctive black and yellow striped patterns. Unlike paper wasps, they have a thick, compact body and short legs. These highly social insects live in large colonies of 1,000-5,000 workers and are particularly aggressive in late summer when protecting their mature nests.

Black widow spiders are shiny black spiders with a distinctive red hourglass marking on the underside of their round abdomen. Females measure 1.5 inches including legs, while males are much smaller. These venomous spiders build irregular, tangled webs close to the ground. Only female black widows have medically significant venom.

Brown recluse spiders are tan to dark brown with a distinctive dark violin-shaped marking on their back. They measure 1/4 to 1/2 inch in body length with legs extending total size to about 1 inch. Unlike most spiders which have eight eyes, brown recluses have six eyes arranged in pairs. These shy, reclusive spiders avoid human contact.

Common house spiders are yellowish-brown to gray spiders measuring 3/16 to 5/16 inch in body length with distinctive dark chevron markings on their abdomens. They build irregular, tangled cobwebs in corners, along ceilings, and in undisturbed areas. These harmless spiders are the most frequently encountered spider species in homes.

Subterranean termites are pale, soft-bodied insects measuring 1/8 to 1 inch long depending on caste. Worker termites are cream-colored, while reproductive swarmers are dark brown to black with wings. These destructive pests live in underground colonies of 60,000 to 2 million individuals and cause over 5 billion dollars in property damage annually in the United States.

Bed bugs are small, flat, reddish-brown insects measuring 1/4 to 3/8 inch long with oval-shaped bodies. After feeding on blood, they become swollen and darker red. These nocturnal parasites hide during the day in cracks near sleeping areas and emerge at night to feed on humans. They're excellent hitchhikers, spreading through luggage, furniture, and clothing.

Fleas are tiny, dark reddish-brown insects measuring 1/16 to 1/8 inch long with flattened bodies designed for moving through pet fur. They have powerful hind legs capable of jumping up to 8 inches vertically. Cat fleas are the most common species affecting both cats and dogs. Adult fleas feed exclusively on blood and can consume 15 times their body weight daily.

Mosquitoes are slender, flying insects measuring 1/4 to 3/8 inch long with long legs and a prominent proboscis. Females require blood meals for egg development while males feed on nectar. These pests produce the distinctive high-pitched whining sound from their rapidly beating wings. Different species are active at different times - some bite during the day while others are active at dawn, dusk, or night.

Box elder bugs are black insects measuring 1/2 inch long with distinctive red or orange markings on their backs forming a V-shape. They have flat, elongated bodies with overlapping wings. These true bugs congregate in large numbers on south and west-facing walls during fall. While harmless, their tendency to invade homes in massive numbers makes them significant nuisance pests.

Brown marmorated stink bugs are shield-shaped insects measuring 5/8 inch long with mottled brown coloring and distinctive white bands on antennae and legs. They emit a strong, unpleasant odor when disturbed or crushed as a defense mechanism. These invasive pests aggregate in large numbers when seeking overwintering sites, making them significant structural invaders in fall.

Ticks are small, blood-feeding arachnids measuring 1/8 to 1/4 inch long before feeding, expanding significantly when engorged. Common species include deer ticks (black-legged ticks), American dog ticks, and lone star ticks. These parasites are dangerous disease vectors that attach to humans and animals, feeding for several days if not removed. They're most commonly encountered in wooded areas, tall grass, and leaf litter.

American cockroaches are the largest common cockroach species, measuring 1.5 to 2 inches in length with a reddish-brown body and yellowish figure-eight pattern behind their heads. Often called palmetto bugs or sewer roaches, they have wings and are capable of short flights. Despite their name, they're native to Africa and the Middle East. These cockroaches are common in commercial buildings, sewers, and steam tunnels.

Voles are small, stocky rodents measuring 4 to 7 inches in total length with short tails, small eyes, and rounded ears. Often called meadow mice or field mice, they have dense brown or gray fur and blunt noses. Unlike true mice, voles have compact bodies and shorter tails. These prolific breeders can produce 5-10 litters per year with 3-6 young per litter, allowing populations to explode rapidly under favorable conditions.

Eastern moles are gray to black, cylindrical mammals measuring 5 to 8 inches long with enlarged front feet adapted for digging. They have tiny, barely visible eyes, no external ears, and short velvety fur. Moles are not rodents but insectivores, feeding primarily on earthworms, grubs, and soil insects. A single mole can tunnel 18 feet per hour and consume 70-100% of its body weight in food daily.

Carpenter bees are large, robust bees measuring 1/2 to 1 inch long that closely resemble bumble bees. The key difference is their shiny, hairless black abdomen, while bumble bees have fuzzy, yellow-banded abdomens. Males have yellow faces and are territorial but cannot sting. Females have black faces, can sting, but are rarely aggressive unless directly threatened. These solitary bees are named for their wood-boring nesting behavior.