The Homeowners Column

The Homeowners Column

Earwigs: a creepy crawly nuisance

Photo of Sandra Mason

Sandra Mason
State Master Gardener Coordinator
slmason@illinois.edu

Big leaves, little leaves; all riddled with holes. What could it be? No critter in sight. No critter to blame. Could it be slithering slimy slugs? But where are the slime trails? Where is the yuck? Then a quick stirring of the mulch and a scream full of earwigs race for refuge. UGH! Earwigs: the poster children for creepy crawly.

Earwigs are usually not a major plant pest, but continued wet weather can spawn large populations of European earwig. Adults are slender reddish brown and approximately 3/4 inch long. The quick identification features are the large, forcep-looking pincers on their hind end. The pincers are used for protection against predators and to capture prey.

Earwigs hibernate in the soil as adults during the winter. In spring, adult females lay 25 to 30 eggs in the soil (not in your ears in case you were wondering). The females provide uncommon maternal care by nurturing and protecting the eggs and young. (Gee, how sweet. Almost makes them lovable).

Earwigs hide during the day. They prefer moist areas. During the daytime, they usually inhabit dark, confined or shaded areas, such as underneath plants, debris, stones, organic mulch, firewood, and flower pots as well as in crevices of outdoor furniture and playground equipment. Landscapers may notice them under loose pieces of bark.

Earwigs are not all bad. They usually eat decaying plants and organic matter. As predators they eat aphids, mites, and insect eggs. However, they are equal opportunity eaters as they feed on the flowers and leaves of ornamental and vegetable plants including bean, potato, beet, cabbage, pea, daylily, zinnia, marigold, petunia, dahlia, hosta, rose and even ripe apples and peaches. They are commonly found lurking in the heads of lettuce and cabbage.

Damaged leaves and petals have a ragged appearance with irregularly shaped holes throughout the leaf. Seedlings and flowering plants can be severely damaged or killed by huge earwig populations.

Earwig management includes sanitation, cultural practice modification, trapping, or insecticides. Remove outdoor harborage such as firewood, plant debris, weeds, and organic mulches from around the house foundation. Avoid overwatering plants and thick layers of organic mulch. Although not as healthy for plants, inorganic mulches such as lava rock or stone are less attractive to earwigs.

A moistened rolled-up newspaper, cardboard paper towel roll, small board or an 8-10 inch section of garden hose can be used to trap earwigs. Place traps in areas showing damage. In the morning shake the traps over a pail of soapy water.

Insecticides are generally not needed as earwigs are usually a short term problem as summer progresses into hotter, drier weather. If necessary, insecticides to manage earwigs include cyfluthrin, permethrin (Eight) and carbaryl (Sevin). Read and follow all label directions. To help protect beneficials and bees, do not spray directly on flowers.

Earwigs that accidentally invade homes are primarily a creepy nuisance as they scurry into hiding places. A quick squish, "capture and release" or handy vacuum cleaner will take care of them. People commonly find them under damp clothes and along baseboards. They don't cause damage or reproduce indoors. To prevent earwigs from entering homes, caulk cracks and crevices around windows and weather strip doors. Before bringing items indoors such as cut flowers, baskets, toys or anything that has been sitting outdoors examine for hitchhiking earwigs. Chemical treatments are generally not necessary indoors.

If you find earwigs fascinating, the Master Naturalist volunteer program may be for you. Training starts August 26. Contact UI Extension at 801 North Country Fair Drive Ste D; Champaign, IL 61821; PH: 217.333.7672 for an application and more info. Or apply on-line before July 21. http://web.extension.illinois.edu/cfiv/mn

Questions? Contact Diane Wilhite our Master Naturalist program coordinator at drwilhit@illinois.edu or PH: 217.333.7672.

Check out the Master Naturalist state website http://web.extension.illinois.edu/mn/ to explore programs in Illinois.

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