JoAnne Skelly: The awful earwig

People are asking about earwigs, which are easily recognized with rather alarming-looking pincers on their tail ends. These unappealing pests can devastate young vegetables, flowers, soft fruits or corn silks.

In spite of this, earwigs, believe it or not, are also beneficial. Being omnivores, they eat aphids, other insects, mites, nematodes, algae and fungi. They eat and break down organic matter, which includes dying and dead plants or ripened fruits.

A negative is that they eat petals, pollen and seedlings too. Typical earwig damage on most plants is small holes in the margins of leaves, although whole seedlings may disappear. They also chew shallow gouges or holes in soft fruits such as apricots, strawberries or raspberries. Earwigs are often blamed for damage more likely caused by slugs, cutworms and other garden pests that, like earwigs, also hide in damp debris. Gardeners often assume injuries to fruit and vegetables are caused by the easily found earwigs, although the earwigs most likely arrived after the initial attackers did their damage.

Deter earwigs from nibbling on plants by circling plants with organic matter, such as compost or chipped bark, to provide a complex soil surface with many alternative organisms on which earwigs can feed. If your yard is already well mulched, and you suspect earwigs are chewing on your seedlings, raise the seedlings indoors and transplant them outside when they are large enough to withstand damage.

Earwigs are easy to trap. Place small cans with a half inch of vegetable oil in them around plants. Bamboo tubes, dampened rolled up newspapers, damp rags or pieces of hose placed near plants also make good traps, because earwigs like dark moist places. A clay or plastic pot filled with damp moss and placed upside down with a small gap at the bottom provides an inviting earwig abode. Place traps near plants just before dusk. Check traps the following morning and shake the trapped insects into a bucket of soapy water to drown them. Reset the traps daily.

Keep earwigs out of fruit trees by encircling the bark with a six-inch band of a sticky barrier. Diatomaceous earth at the base also works as a barrier. Remove boards, rubbish and plant debris in areas you want to protect to reduce hiding places. Raise pots and plant containers on stands or pot feet to deter earwigs from gathering there.

Don’t worry. It’s a myth that earwigs crawl into ears to burrow into the brain to lay eggs.

JoAnne Skelly is Associate Professor & Extension Educator, Emerita at University of Nevada Cooperative Extension. She can be reached at skellyj@unce.unr.edu.