German roaches are arguably the largest known and most battled against pest. About 5/8 inch long and light to medium brown in color with 2 distinctive stripes on the pronotum (area behind it's head), they can be difficult to control. Female German roaches carry the egg sack protruding from their abdomen until they are ready to hatch. This behavior is part of the reason for their high reproduction and survival rate. The adult females produce about 5 or 6 egg sacks in a lifetime (one about every 6 weeks or so). Each sack will contain around 30 or 40 eggs. It takes about 28 days for the eggs to hatch and from a little over a month to several months for the nymphs to mature.