Like cockroaches, crickets have a gradual metamorphosis. The young, or nymphs, look like adults, except their wings are not developed fully. The two most common types of crickets found are the house cricket and the field cricket.
House crickets live outdoors, but will come inside in great numbers. Adults are 3/4-1 inch long and light yellowish-brown with three dark bands on the head. They will eat almost anything and will chew on damaged silk and woolens. House crickets are nocturnal, staying hidden during the day. They have a distinctive chirping sound. House crickets can be found in warm places like kitchens, basements, in cracks and crevices and behind baseboards.
Field crickets are widely distributed over the United States. This cricket is slightly longer than the house cricket and is dark brown to grey or black. Field crickets prefer to live outside, feeding on plants, but will come inside if food sources dry up or there or unfavorable extremes in temperatures. Field crickets are often attracted to lighted areas at night, thus, problems with crickets can be lessened by turning off lights during periods when crickets are numerous, or at least manipulating lights so the crickets are less bothersome.