Iowa Insect Information Notes



The field cricket is one of the most common household accidental invader insect pests. There are several species of field crickets ranging in size from 1/4 to 3/4 inch, but the best known is the black field cricket, a large, shiny black insect. Like other accidental invaders, field crickets spend most of their life outdoors where they feed, grow, develop and reproduce. Only during a limited portion of their life cycle do they wander indoors by mistake and create an annoyance.

Field crickets spend the winter as eggs laid in the soil. These eggs hatch in late spring or early summer, and tiny immature crickets called nymphs begin to feed on a variety of succulent grasses and weeds. The nymphs look like the adults except for their smaller size and the absence of wings. Nymphs develop into adults within approximately 90 days. The adults mate and lay eggs in late summer before succumbing to old age or freezing temperatures in the fall.

Chirping, one of the hallmarks of crickets, is done only by the males as a way to attract the females of their own species. Chirping is produced by rubbing the wings together.

There is no single, perfect solution for the control of crickets that are invading the house. Often some combination of the following suggestions will work. Ultimately, cricket problems end in the fall when the adults are killed by heavy frost or freeze.

1. Seal cracks, gaps and holes in foundation, siding, windows, doors, screens, and other possible entry points. Remove vegetation and debris from next to the house that serves as a hiding place or breeding site.

2. Reduce the number of pests at the source if possible. Spraying outdoor use insecticides on lawns, fencerows and other cricket habitats may help reduce the population of rickets. Spraying in mid summer when crickets are small is more effective than late summer applications.

3. Use barrier perimeter sprays on and along the foundation to stop migrating invaders. In years of abundance the barrier should extend all the way to the source if possible; that is,all the way to the fencerow, ditch bank or other identifiable habitat for crickets.

4. For invaders already inside the house, vacuum or sweep them up and discard.

For more information on insecticides that can be used outdoors please see "Insecticides in the Home Landscape and Garden." Indoor treatments with residual insecticicides have little in any benefit. Do not use lawn and garden insecticide concentrates indoors. The fly swatter, rolled up magazine, or vacuum cleaner are the easiest methods to eliminate crickets that are inside.

Updated 07/14/2005 - 1:40pm