In the Pacific Northwest, there are four cockroach species that may be encountered in structures. Each of these species prefers different areas in which to live and hide. Because various combinations of species can be encountered at the same time, it is essential to accurately identify the species before starting control methods. The American Cockroach, German cockroach, brown-banded cockroach, and Oriental cockroach can all be found infesting homes and businesses in our region.

American Cockroach

The American cockroach, Periplaneta americana, is the largest of the four species. The adult is 1 ½ inches long, reddish-brown to brown, with a light yellow or tan band around the edge of the shield behind the head.

Both sexes have well-developed wings and can fly, although they seldom do. The wings of the male extend slightly beyond the tip of the abdomen, while those of the female do not. The American cockroach is rare in Washington State, and most infestations are brought in with produce or in the furniture of persons moving from warmer climates. When established, this species prefers warm, moist environments.

Brown-Banded Cockroach

The adult brown-banded cockroach, Supella longipalpa, looks almost identical to the German cockroach, but it lacks the distinctive dark brown lengthwise stripes on the shield behind the head.  The wings of the male completely cover the abdomen, whereas the wings of the female are short and never cover all of the abdomen. The female’s abdomen is also much broader and more rounded than the male’s.

These roaches are very active. Adult roaches will jump when disturbed, though only the males can fly. Brown-banded roaches will live anywhere from 3 – 11 months, are more likely to be found in private residences than in commercial buildings, and are more common in eastern Washington than western Washington. These roaches will infest any room, while German roaches prefer kitchens and bathrooms.

German Cockroach

The German cockroach, Blattella germanica, is the most commonly encountered cockroach in apartments, restaurants, hospitals, or other buildings throughout the Pacific Northwest. They frequent areas in which food is stored, prepared, or served.

The adult is ½ inch long, pale brown, with two dark brown lengthwise stripes on the shield behind the head. Adults are fully winged, but rarely fly. Under ideal conditions, adults live up to 12 months.

A female produces eight egg cases during her lifetime, each case containing 30 to 48 eggs, allowing this cockroach to multiply more quickly than any of the other cockroaches found in Washington. Because the German cockroach produces more eggs and has more generations per year (3-4) than other local species, a troublesome infestation can rapidly develop after only a few individuals are introduced.

Oriental Cockroach

The oriental cockroach, Blatta orientalis, is uniformly glossy and dark brown to black as an adult. The female is 1 ¼ inches long, with a broad abdomen and stubby wings. The male is 1 inch long, slender, and has wings that cover two-thirds of the upper abdomen. Neither sex will fly or even run very quickly when disturbed. Adults will live anywhere from 1 – 6 months.

How Did I Get Roaches?

Cockroaches are commonly introduced into buildings with groceries (especially bagged potatoes and onions), beverage cartons and cases, and used furniture and appliances. Adults may also migrate from other nearby infested dwellings. In this area, most migration occurs along plumbing, electrical wires, utility tunnels, or between apartments.


Cockroaches are commonly associated with unsanitary conditions. They may be found breeding in garbage storage, sewage systems, and septic tanks. Roaches prefer warm environments, and are usually most active at night. Cockroach feces, saliva, and body parts carry allergens that can cause allergic reactions or trigger asthma symptoms. They have also been known to passively transport pathogens to humans, including E. coli and Salmonella.


We understand that your needs can be urgent. Our goal is to provide you with a pest-free home or business as quickly as possible. Call before noon Monday – Friday and a Sentinel professional will be at your door the SAME DAY!


Have any pest related questions or in need of pest control services?

Our office staff is trained to answer any pest control related questions! Once scheduled with us, an appointment confirmation will be emailed within 15 minutes with your appointment information and a picture of your technician!


We’ll give you a call and schedule the best time for you!