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Pest Guide

Outdoor pests that get inside your home can cause unwanted and even dangerous infestations. Some of these pests can bite, secrete foul odors or cause damage to your family, possessions and home structure.

Learn more about common pests and find out what our trained technicians can do to protect your family and home.


Acrobat Ants

This small (1/16-1/8”) dark brown to black ant is often seen trailing up the outside of structures going to and from a nesting site. They are easily identified by the distinct ‘Valentine heart’ shape of their abdomen when viewed from above.

Carpenter Ants

This wood destroying member of the ant family is fairly easy to recognize. Workers will range in size from about ¼” to almost 1” in length and color will vary from all black to a black/brown combination depending on the species. If you see ants in your home that are ¼” or larger, then they are likely to be carpenter ants.

Citronella Ants

The females are yellow/orange in color and about ½ -5/8” long with wings that are dark at the base and almost clear at the tips. Most people’s first and only encounter with them is when a reproductive swarm occurs in or near a structure.

Odorous House Ants

Workers are about 1/16-1/8 inch long, black in color and tend to walk in a quick, erratic pattern.  Their name comes from the ‘rotten coconut’ like odor given off when they are crushed. This is the quickest way to identify this ant.

Biting Insects

Bed Bugs

The adult bed bug is reddish brown, about 3/16ths of an inch long, oval and flattened in shape. Nymphs are smaller and may appear reddish brown with a tan outer margin and newly hatched nymphs may appear all tan until they take a blood meal.

Blow and Bottle Flies

Adult Blow/Bottle flies will range in size from 1/8” to 5/8” and will be wholly or partly metallic blue, green, bronze or black.

Cluster Flies

One of the most commonly encountered flies in structures, the Cluster Fly’s name is derived from their habit of forming compact clusters of overwintering individuals. They will vary in size slightly but are generally about 3/8” – ½” long and have a dull gray to black appearance.  This fly is NOT associated with filth or the presence of a dead animal.

Drain Flies

This particular fly is fairly easy to identify. They are 1/16 to 3/16” long, usually grey to back and fuzzy in appearance. The most distinct characteristic is the ‘inverted valentine heart’ shape when they are at rest. These flies breed in moist, decaying organic material. As they are weak fliers, their presence is indicative of a nearby breeding source.

Fruit Flies

Fruit flies get their name from their fondness for laying eggs in decaying and fermenting fruits and vegetables. Materials they commonly infest include bananas, grapes, pineapple, peaches, tomatoes, potatoes and fermenting liquids such as wine, vinegar, cider & beer.


Adults are typically grey to black with various markings and range in size from 1/8”-3/8”. Several species of mosquitoes are found in Pennsylvania.

Fabric Pests

Carpet Beetles

Carpet beetles are another fabric pest whose damage is often confused with Clothes Moths. They damage the same fabrics (wool,silk,etc.), but damage appears as random holes with no white-ish webbing on the fabric. Fecal material is sand-like and takes on the color of the fabric being consumed.

Clothes Moths

The Clothes Moth is a small ¼ “long moth that is uniformly tan in color. They shun light and prefer to run rather than fly. The larvae of the Clothes Moth prefer to feed on fabrics made of wool, silk, cashmere, or other animal hairs. Damage to fabrics will present with holes and, in the case of the webbing clothes moth, white silk webbing. Fecal material is a sand-like material that takes on the color of the fabric being consumed.

Silver Fish

This primitive insect gets its name from the metallic grey sheen of the scales covering its body. Adults are up to 3/4” long. The young resemble adults, albeit smaller.

Occasional Invaders

Boxelder Bugs

This black and orange bug is about 1/2-3/4” long and gets its name from the fact that it is a major pest of Boxelder trees.

Brown Marmorated Stink Bugs

Shield shaped and mottled brown in color with 2 white bands on the antennae and along the sides of the abdomen.  Adults are about ½-5/8” long.

Cave or Camel Crickets

This light to dark brown cricket will range in size from ½” to 1 ¼” long and has a hump-backed appearance when viewed from the side. Their extremely long antennae and long hind legs give them an unusual look that many people describe as a cross between a Cricket and a Spider. Unlike their Field Cricket cousins, they lack the ability to ‘chirp’.


The Common House Centipede is yellowish-grey in color with 3 dark stripes that run the length of the body.  They range between 1-1 ½” long.  The adult has 15 pairs of legs and long antennae making them appear much larger. Also known as the ‘thousand legger’.


Adults are about ½-1” long and vary in color from pale brown to a reddish brown with paler legs. They are easily identified by the pincer-like appendages on the abdomen.

Field Cricket

This light to dark brown cricket will range in size from ½” to 1 ¼” long and has a hump-backed appearance when viewed from the side. Their extremely long antennae and long hind legs give them an unusual look that many people describe as a cross between a Cricket and a Spider. Unlike their Field Cricket cousins, they lack the ability to ‘chirp’.

Flour and Grain Beetles

There are a number of common species of flour and grain beetles including, The Red Flour, Confused Flour, Saw-toothed Grain, Merchant Grain and Foreign Grain Beetles. Identification requires the use of a magnifier or microscope. In general they are 1/32”- 1/16” long and reddish brown to brown in color.

Indian Meal Moths

The Indian Meal Moth (IMM) is one of our most commonly encountered stored product pests. The adult moth is approximately ½” – 5/8” long with a distinct two-tone appearance when at rest with their wings folded back over the body. They will be grey on the front half and reddish brown on the rear half with a distinct line between the colors. Larva (caterpillar) are about ¾” long, cream color with a darker head.

Ladybird Beetles

Ladybug is the common name used for a family of small oval beetles approximately 1/8”- 3/16” long. Color and markings will vary by species from yellow to bright orange with various markings (spots) of brown, black and white. There are even some species which are all black or black with orange markings.


Millipedes are an outdoor pest which will occasionally migrate indoors in search of moisture. They are approximately 1-1 ¼ inches long, with a thin brown body and 2 pairs of legs per body segment. They feed on decaying wood and other organic debris.

Old House Borer

The Old House Borer (OHB) is a wood infesting beetle. Adults are 5/8”-1” long with antenna about the same length as the body. They are grey/black in color with two dark colored ‘eyes’ on the wing covers. Adults are not often seen.

Pill Bug

Pill/Sow bugs are land dwelling Crustaceans, not insects. Adults are ½”- 5/8” long and have a grey, segmented upper shell. Pill bugs have also earned the nickname ‘roly-poly’ because they will roll up into a tight ball when disturbed.


American Cockroach

Reddish-brown to dark brown with light marking on thorax species of cockroach are large approximately 1 3/8” – 2 1/8”.

Australian Cockroach

This large cockroach is reddish-brown in color and typically 1 ¼” in length; long antennae and spiky legs.

German Cockroach

Adult German Roaches are tan to light brown in color and have two longitudinal black stripes on the pronotum (the plate between the head and the wings).  Approximate size is 5/8”-3/4” long.   They shun light and are very poor flyers. The German cockroach is by far the most commonly encountered species of cockroach.

Oriental Cockroach

This large (1”-1 ¼” long) cockroach is commonly called a Water bug. Adults are very dark brown, almost black in color. Males have wings that cover about 2/3 of the body but are unable to fly. Females have rudimentary wing pads and are also unable to fly.

Pennsylvania Wood Roach

The adult male is 1”-1 ¼” long, dark brown with yellow on the sides of the thorax and forward half of the full length wings. Females are ¾”-1” long with wings that only cover two thirds of the body and are functionless.



Several species of Bats inhabit Pennsylvania with the most common being the Little Brown and the Big Brown Bats. These bats are small, brown, winged mammals up to about 5” body length and up to 13” wingspan.


The Chipmunk is a small ground squirrel. Adults are about 10” long including a tail that is 3”- 4” long. They are easily identified by the blackish stripes running lengthwise down the back and sides of their overall reddish brown fur.

Flying Squirrels

These small squirrels (about half the size of a gray squirrel) are usually grey/brown on their backs with a light underbelly and a distinct black line on their sides.  They do not actually fly, but glide with the help of loose skin ‘flaps’ between the fore and hind legs. They have been known to glide as far as 80 yards!

Grey Squirrels

The Grey Squirrel is one of the most recognizable members of the rodent family. Adults are 18”- 20” long with half of that being their characteristic, broad bushy tail. Color is typically grey with some brown or rust colored markings on the sides. Melanastic (black phase) grey squirrels are not uncommon and this condition is prevalent in portions of Delaware and Montgomery Counties.

Ground Hogs

Adults are brown to grey in color, 12-18 inches long and can weigh from 8-16 pounds.   Ground Hogs are one of the largest members of the rodent family. They can be found everywhere from cities to farm fields.

Meadow Vole

The vole (often mistaken for a mole) is a member of the rodent family commonly found in fields and meadows. Adult voles are dark brown in color with a body length of 4”-5” with a short (1/3 the length of the body) tail and a ‘stocky’ build.


The most common mouse species encountered in structures are the House Mouse, White Footed Mouse and the Deer Mouse. Adult mice are typically 2.5-4” long and color varies from grey to reddish brown with the Deer and White Footed mouse being bicolored with a lighter underbody. Mice are prolific breeders with litters averaging 6 young which are capable of breeding in as little as 5 weeks!


The mole is a small mammal that spends most of its time underground. Adult moles are 4’-5’ long, have dark grey fur with silvery highlights and very conspicuous, paddle-like front feet.


A mature Opossum is 24-40 inches long including a tail which is 10-12 inches long, they weigh 4-12 pounds. Fur is usually light grey with darker brown legs and feet and they have a pointed snout.


Raccoon are probably one of the most recognizable wild animals. The raccoon has a stocky build, are 28”-38” long including the tail and weigh from 10-30 lbs. Fur is a grizzled brown/black and the bushy tail is ringed with light and dark bands. Their snout is long and slender and a black band across the eyes gives them a masked appearance.


The Norway rat, which is the most commonly encountered rat in our area, can have a body length of 7-9.5” long with a tail length of 6-8”. Body color can vary from brown to grey to black with a lighter underbody.



Perhaps no other pest found in homes invokes the same kind of fear and loathing as spiders. From the time we are kids, we are taught that spiders are scary, creepy and evil. Spiders are actually beneficial.

Stinging Pests

Bald Faced Hornets

The Bald Faced Hornet is actually a member of the yellow jacket family so their biology is very similar. The coloring is black and white with the ‘bald faced’ name coming from the white patch on the front of the head. Adult workers are about 5/8-3/4” long.

Bumble Bees

They are ¼ – 1” long with a robust body form, mostly black with yellow markings and an overall ‘fuzzy’ appearance. These beneficial pollinators are one of the most recognizable species of bees.

Carpenter Bees

The Carpenter Bee is a large, robust bee. They are primarily black in color with yellow marking that resembles a Bumble Bee, however the abdomen is sparsely haired and will appear shiny.

Cicada Killer Wasp

They are one of the larger members of the wasp family with adults about 1-1 5/8” long primarily black with yellow markings. The Cicada Killers names is derived from the fact that it hunts and provisions each nest cell with a Cicada as food for it’s young.

Honey Bees

Adult workers are typically orange and black in color and range ½-5/8” long.  Their bodies are covered with fine hairs. Queens and males are similar in appearance but slightly larger than the workers.

Mud Dauber Wasp

There are three types of Mud Daubers in Pennsylvania, they black and yellow MD, the organ pipe MD which is uniformly black, and the blue MD which has an iridescent blue color.

Paper Wasps

Adult Paper Wasps can be brown with a reddish marking or dark brown/black with yellow markings. They are about 5/8-3/4” long.  When flying they have a characteristic ‘droop’ of the rear legs.

Yellow Jackets

Yellow Jackets are named from their yellow and black bodies. Adult workers range in size from 3/8”-5/8” long. They are a social wasp that live in large colonies.

Wood Destroying Insects 

Powderpost Beetle 

There are several species commonly called Powder post Beetle. All of them are very small, 1/16”- 1/8” long with a slender body and are usually reddish brown to dark brown in color.  Rarely are the adults of these beetles seen.

Subterranean Termites

Perhaps no other pest strikes more fear in homeowners than Termites. The most commonly seen caste member of the termite colony is the Alate, or swarmer. These winged insects are reproductive termites that leave the nest in the spring to start new colonies. They are black in color with a cigar shaped body about 3/16” to ¼” long, with 4 wings that extend back twice the length of the body.


There are 9 common species of woodpeckers found in Southeastern Pennsylvania. More information regarding identification of individual species is available on the website of the Pennsylvania Game Commission (wildlife/wildlife notes/woodpeckers).

Ticks and Mites

Clover Mites

Adults are small (about 1/64”) and color will vary from red to brown to olive green.  The name Clover Mite comes from the fact that Clover is one of the preferred host plants of this mite.


While there are hundreds of species of fleas, the most commonly encountered flea in homes is the Cat Flea. Cat fleas are also the primary fleas found on dogs.  Adult are up to 1/8” long, reddish brown to black in color. Their bodies are vertically flattened to enable them to move through hair and fur easily. Their hind legs are highly adapted for jumping.


While there are more than 25 species of ticks in Pennsylvania. The 4 most commonly encountered are the American Dog Tick, the Blacklegged (Deer) Tick, the Lone Star Tick and the Groundhog Tick.