Earwig

The earwig, often misconceived due to its name, is a small insect with pincers at its rear end. It inhabits various environments and feeds on both plant material and small insects.

Host Plants

• Mainly dahlia, clematis, and chrysanthemum.
• Earwigs prefer decaying plant and animal matter but also feed on a wide range of flowering and other plants.
• Earwigs are attracted to young foliage and seedlings, potted plants, and leafy greens, including basil, lettuce and celery.
• They rarely cause damage to hard fruits like apples but will occasionally cause damage to soft and stone fruits such as strawberries, raspberries, nectarines, and apricot.

Regions impacted

Earwigs can be found in almost any growing zone, although they are more likely to inhabit warm, humid climates.

Earwig Description

Earwigs have pedigree, having evolved from the insect order Dermaptera, ancient bugs that crawled the earth over million years ago. They are slender reddish-brown insects from ¼ to 1 inch long. Earwigs have six legs and delicate antennae that measure half again the size of their body. They have two pairs of wings, although not all species fly; most flights are limited to short bursts.

Earwigs sport nasty-looking pincers on their tail end, from which their sobriquet, “pincher bugs,” derives. Their more traditional name, earwig, also emanates from these pincers, derived from an old European myth that they crawl into people’s ears and tunnel into their brains when sleeping. This myth has no support from science, but there is no question these appendages can evoke something sinister in the more superstitious gardener!

Earwig Life Cycle

Adults overwinter under garden debris, stones, and boards and in soil. Adult females emerge from overwintering to lay eggs in the ground in spring. They produce about 40 to 50 eggs in underground tunnels and are diligent mothers in caring for their young and protecting them from predators. They hatch within a week into nymphs which resemble smaller versions of adults. They shed several skins, and ten weeks later, they reach adulthood.

Damage and Detection

• As omnivores, earwigs primarily feed on decaying organic matter and insects. They are beneficial in compost piles and as pest predators but can be a nuisance as they are attracted to moist areas around and inside homes.
• They become pests when they come indoors and when outdoor populations get out of control.
• Earwigs enter households through cracks and other openings. They like water sources such as bathrooms, laundry rooms, and kitchens.
• In gardens, they chew holes in plant leaves and flower petals and burrow them into flower buds.
• Some types of earwigs also target seedlings, arresting the development of crop and garden plants. Damage often occurs after rainy weather as earwigs seek dry shelter and climb into plants and onto leaves.
• Earwigs congregate during the day and often live together under piles of lawn debris or mulch. When startled or uncovered, they scatter surprisingly quickly.

Prevention and Control

• Earwigs are not as much of a threat to your garden as other pests, though they can be annoying.
• Expect more earwigs during rainy periods, and prepare accordingly by being diligent about removing plant debris and other hiding places.
• Clean up and remove garden debris and mulch from around foundations since moist areas represent hiding spots for earwigs.
• Move firewood piles and other sources of damp habitation, creating a perimeter around the house that is free of organic materials.
• Earwigs are attracted to light, so eliminate or reduce lighting around foundations.
• Keep trees or shrubs that cause or represent shady areas around the house trimmed. Ensure water drainage from downspouts and gutters drain away from home.
• An effective way to trap earwigs is with an oil pit trap. Use a small plastic container with a lid, and cut a pencil-size hole in the top. Place a shallow pool of vegetable oil in the container with a touch of soy sauce for aroma. Replace the lid, and put the trap where earwigs are likely to be present. Empty and refill traps every few days.
• Birds and toads are natural predators, and earwigs are natural predators of aphids, maggots, and other smaller pests.
• The conundrum for the gardener is whether to leave the earwigs alone to eat the aphids and others pests or to attempt to manage their population to protect one’s plants. Generally, damage inflicted by earwigs is modest and regular maintenance and cleanup should result in an appropriate population of earwigs to help attack other more damaging pests.