Adult German cockroaches are between 1/2" to 5/8" long. They pale brown to tan and have two parallel black streaks on their pronotum (shield-like segment behind their head).
Males are narrower than the females. Both sexes have wings but cannot fly in the Bay Area.
Immature (nymphs) cockroaches are 1/8" long when they hatch and are mostly dark except for a light area on the back of the second and third segments. As they grow (molt) the light area becomes bigger. In the later stages the two parallel black streaks become more noticeable.
The adult female produces four to eight light brown egg capsules in her lifetime. Each capsule is about 1/4 inches long and contains 30 to 40 eggs. The female carries the egg capsule partially with in her abdomen until just before the nymphs are ready to emerge.
The nymphs emerge from the egg capsule 28 to 30 days and live and feed in the same areas as the adults. The nymphs will molt six to seven times before they are adults. It takes around three months to mature and there will be up to four generations per year. Under perfect conditions one fertile female can produce a million descendants in a year. They can feed upon almost anything with nutritive value inside a home.
This roach is the number one household problem in the United States. They are usually found infesting the kitchen and/or bathrooms, but has the ability to live anywhere inside of a heated structure. They live in dark, secluded harborages such as cupboards, behind cabinets, in wall voids or around motor housings in appliances.
German cockroaches are usually introduced to a home through boxes, cartons, grocery and produce bags, and most commonly in second hand appliances. This roach is known to carry disease organisms on their bodies which can be transferred from contaminated items in the home. They stay hidden during the day and come out at night. If they are seen during the day there is a tremendous population in the home.
To control the german cockroach multiple treatments may be needed. Baits or chemicals to kill the adults and nymph stages will be necessary. Also a growth regulator to sterilize the nymphs will be used. Preparation by the resident will be needed. Roaches are the only insects that can adapt to chemicals.