For many folks, the word earwig brings on thoughts of a creepy old tale. It was once believed that earwigs would enter the ear of a sleeping person, bore into the brain and lay eggs (hence the name). Even movies like Star Trek II: The Wrath of Khan played on that repulsive image. But you can relax – it’s just an old superstition, although these insects do prefer to be in dark, tight spaces.
It has also been called a pincer (not pincher) bug because of the intimidating tail end pincers. Generally, they do not harm people and their pincers are their defense system. However, I must admit I was a little squeamish when I opened my front door to find masses of them crawling everywhere, including around my porch light. That’s when I remembered that they are nocturnal and are attracted to lights at night.
Although they are omnivorous (they eat both plants and animals), they are considered scavengers rather than predators. You should be concerned about an earwig invasion if you are growing vegetables, sweet corn, stone fruit, or soft fruits such as strawberries and apricots. Also, they enjoy feasting on some herbaceous flowering plants such as zinnias, marigolds, and dahlias.
However, if your landscaping is primarily lawn, trees and woody ornamentals, earwigs should not present a threat. In fact, they also can have a beneficial role and have been shown to be voracious feeders of aphids and insect eggs.
Earwigs feed most actively at night and seek out dark, cool, moist places to hide during the day. Some basic measures can be taken to reduce the population of earwigs and other creepy-crawly visitors inside and outside of your home.
- Eliminate dense undergrowth of vines, ground cover (like ivy) and weeds around vegetable and flower gardens. Prune away fruit tree suckers and don’t let mulches or compost piles stay too wet.
- Move piles of debris, yard waste, boards, fire wood and flower pots away from the house.
- Avoid over-watering lawns and flowerbeds. Drip irrigate where possible to reduce surface moisture.
- Seal up small cracks around the foundation of your home and near windows, doors or entryways.
- Eliminate damp conditions in crawl spaces, around air-conditioning units and leaky water faucets.
- Don’t leave drying clothes or damp pool towels out overnight.
- Trapping will reduce earwig populations to tolerable levels. A low-sided can, such as a cat food or tuna can, with 1/2-inch of oil in the bottom attracts them. Dump and refill every morning.
- Just before dark, set out very damp rolled-up newspaper, wet cardboard, or a short piece of hose. Earwigs will happily tuck themselves in, making it easy for you to dispose of them.
- For stone fruit trees, trunks can be treated with Tanglefoot, a sticky substance to prevent earwigs from climbing up the trunks. Harvest fruit as soon as it ripens.
- Finding earwigs indoors can be aggravating (like when one bit my husband in bed), but present no health hazards. Sweep or vacuum them up and seal entry points.
Most importantly, cooperate with Mother Nature! There is no need to use pesticides which can disturb the balance of beneficial (good) bugs vs. bad bugs. Instead, use the rules of IPM (Integrated Pest Management) to identify the pest, monitor, determine the level of damage you can tolerate, and control with any of the above techniques. You can also effectively create an environment that welcomes the predators of earwigs: birds, bats, frogs, toads, spiders, tachinid flies and reptiles including lizards and snakes (gee – I’m not so sure I like that one).
As ugly and annoying they can be, keep in mind that earwigs are beneficial when feeding on aphids, so exterminating them is not a good idea. Measure their benefits against any damage they may cause in your specific plants. Like much of eco friendly gardening, it’s about observing your garden and finding a balance between intervening and letting nature run its course. A valuable tool is the website: http://www.ipm.ucdavis.edu. Use the search function for specific earwig information.