[Pest ID] German Cockroach

GERMAN COCKROACH
Order/Family: Blattodea/Blattellidae
Scientific Name: Blattella germanica (Linnaeus)

Description

The adult males are somewhat narrower than the females when viewed from below. The nymphs, 1/8-inch long when they emerge from the egg capsule, are almost uniformly dark except for a light tan area on the back of the second and third segments. As they develop, the light tan area becomes larger until, as mature nymphs, they have two parallel black bars separated by a light tan area.

Biology

The female carries the egg capsule partially within her abdomen until just before the nymphs are ready to emerge. About one to two days before hatching, she drops the egg capsule in a protected area. Nymphs molt six to seven times before becoming adults. This requires about 103 days; thus allowing three to four generations per year.

Habits

German cockroaches are the most common household insect within the United States. This pest typically infests kitchens and bathrooms but will live anywhere inside heated structures in which there is food, water and harborage. Cockroaches feed on all types of human food.

German cockroaches are active at night, leaving their harborage to find food and water. They remain hidden in dark, secluded harborage areas where they spend 75 percent of their time. At most, only one-third of the population forages at night.

Control

An effective cockroach management program depends on good sanitation. Cleanup to reduce cockroaches in the home and office environment must focus mainly on food residues. It is critical to reduce clutter. Vacuum cleaning can be used to physically remove exposed cockroaches. Containerized, paste, dry, and gel baits are effective products for eliminating cockroaches. To maximize effectiveness, paste, gel and dry baits should be applied with a syringe-like dispensing tool in many small dabs or spots that are close to harborage sites. Small, plastic bait containers should be placed as close as possible to the dark concealed spots where cockroaches are living, preferably adjacent to edges and corners. Large populations of cockroaches can be reduced or eliminated with careful application of sprays and dusts.

Up Close

•1/2- to 5/8-inches long when mature

•Light brown to tan

•Have fully developed wings

•The pronotum (the shield-like segment behind the head) has two dark parallel bars on it

•The purse-shaped egg capsule (ootheca) is light brown in color, 1/4- to 3/8-inch long, and typically has 15 to 20 eggs per side

•During her lifetime, the female German cockroach produces four to eight egg capsules, each of which contains 30 to 40 eggs

•Adults live 100 to 200 days

•Established German cockroach populations consist of about 75 percent nymphs

•The most common household insect within the United States