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German Cockroach

Blattella germanica · Cockroach

Scientific Name

Blattella germanica

Category

Cockroach

Size

0.5 to 0.6 inches

Color

Light brown with two dark parallel stripes behind the head

Lifespan

100 to 200 days adult, plus 2 months as nymph

About the German Cockroach

The German cockroach is the most common and most destructive indoor cockroach in Michigan. One female produces up to 6 egg capsules (each containing 30 to 40 eggs) in her lifetime. German cockroaches trigger asthma and allergies, contaminate food, and spread salmonella, E. coli, and staphylococcus.

Habits & Behavior

German cockroaches hide in warm, humid, dark locations within 10 feet of food and water. They cluster in kitchen cabinets near the dishwasher, behind and under appliances, inside motor housings, in bathroom vanities, and inside electronics. They are nocturnal and avoid light.

Signs of a German Cockroach Infestation

Sign #1

Live roaches scattering when a light is turned on at night

Sign #2

Pepper-like fecal specks clustered in cabinet corners, behind appliances, inside drawer tracks

Sign #3

Oothecae (egg capsules) 1/4 inch long, tan-colored, glued to hidden surfaces

Sign #4

Musty, oily odor in severely infested kitchens

Sign #5

Shed exoskeletons in cabinet corners and appliance motor areas

Sign #6

Live roaches visible during the day in heavy infestations

German Cockroach Pressure in Michigan

German cockroaches in Metro Detroit concentrate in apartment buildings, multi-family housing, rental duplexes, and older urban housing with shared walls. Hamtramck, Highland Park, Detroit, Pontiac, Lincoln Park, and Hazel Park have the highest rates due to dense multi-family stock. Infestations spread through shared plumbing and electrical chases.

How BTR Treats German Cockroach Infestations

BTR uses a three-stage gel bait and insect growth regulator (IGR) program. No spraying in kitchens. Gel bait is placed directly into harborage zones. IGR applications sterilize reproducing adults. Crack-and-crevice dust is applied in wall voids. Most Metro Detroit German cockroach treatments require 3 visits across 6 weeks. Multi-unit buildings require all adjacent units treated simultaneously.

Prevention Tips

Fix leaking faucets and pipes immediately. Store food in sealed containers. Empty garbage nightly. Deep-clean appliance motor housings annually. Inspect and treat any used appliances, furniture, or electronics brought into the home.

Frequently Asked Questions About German Cockroachs

How did I get German cockroaches?

German cockroaches rarely enter through exterior gaps. They almost always arrive hidden inside used appliances, used furniture, cardboard boxes (especially from grocery stores), grocery bags, and personal luggage. In multi-family buildings, they spread through shared wall voids, plumbing chases, and electrical conduits.

Why does BTR not spray for German cockroaches?

Broadcast spraying repels German cockroaches into deeper wall voids and harborage zones, making infestations harder to eliminate. Modern gel baits are eaten by the cockroach, carried back to the harborage, and shared through colony interactions. Bait and IGR combined eliminate colonies more completely than sprays.

How long does it take to eliminate German cockroaches?

Most Metro Detroit infestations require 3 visits across 6 weeks. Severe infestations in multi-family buildings require 4 to 6 visits. Adjacent units must be treated simultaneously to prevent reinfestation. BTR offers a 30-day warranty with 50 percent off the second treatment.

Are German cockroaches dangerous?

Yes. German cockroaches are a leading asthma and allergy trigger in urban environments. Their feces, shed skins, and saliva contain proteins that cause respiratory reactions in sensitive individuals. They mechanically spread salmonella, E. coli, staphylococcus, and other bacteria across food-preparation surfaces.

Can I eliminate German cockroaches with store-bought sprays?

Not usually. Store-bought sprays repel cockroaches without killing the colony. Professional gel baits deliver active ingredients into hidden harborage zones. DIY attempts often worsen infestations by driving cockroaches deeper into walls.

German Cockroach Problem? BTR Can Help Today

Free inspection. Licensed Michigan exterminators. 90-day warranty on most services.

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