A Contradiction – Earwigs are Both a Beneficial Insect and a Garden Pest.

Due to the mild winters of recent years, earwigs have successfully migrated north and established themselves in the yards and gardens of northwestern Ontario. By far, earwigs seem to be the insect that makes humans cringe the most. When mentioned in conversation, even those that have never seen an earwig have a look of disgust on their face and a comment to match.
But before we are too negative about earwigs, we must review their positive side. Yes, earwigs do have some redeeming qualities. They clearly walk the line between being a beneficial garden insect or a garden pest. Most people do not realize that earwigs are omnivorous, which means they eat both meat and plants. In the insect world, this means that earwigs also eat other insects, their eggs and larvae. The earwig is a scavenger, roaming the yard and garden for delicacies like aphids, mites, nematodes, slugs and their eggs, other soft bodied insects and decaying plant matter. If none is found then they will seek their food source from live plants, which is when the gardener notices the damage and complains about the destruction they cause.
Earwigs will eat ornamental and vegetable plant leaves and tender roots, particularly dahlias, marigolds, zinnias, sunflowers, grasses, butterfly bush, hollyhocks, lettuce, strawberries, potatoes, roses, bean and beet seedlings, berries, apricots, peaches as well as the silk of sweet corn. Earwigs are also notorious for eating holes in buds and blooms of Clematis while leaving the foliage alone.
When serious feeding damage occurs, leaves will have numerous, small, irregular holes, giving the plant a ragged appearance. As this type of damage can often be mistaken for the same type of damage caused by other pests such as slugs, it is important to be sure you’ve identified the real culprits, by looking for feeding earwigs on your plants after dark.
Earwigs are brown to black, glossy flattened insects that measure one to three centimetres long. They have a pair of curved pincers or forceps emerging from the tip of the abdomen. They use their pinchers for hunting and securing other insects. Adults may or may not have wings, but they rarely fly. As larvae, earwigs resemble adults because they develop from egg to adult through gradual metamorphosis, with four to five nymphal instars or stages, similar to grasshoppers.
During the spring or autumn, females lay 20 to 50 smooth, oval, pearly-white or cream-colored eggs in the upper five to eight centimetres of soil. They are unusual among insects in that the female fusses over her eggs and nymphs, and uses her pincers to protect them. Most species have one generation a year, but in milder climates, some remain active all year. Both eggs and adults overwinter in the soil or under garden debris, stones, and boards. Adults and the young require moisture to live which is why they are found in damp areas. Earwigs are unable to crawl long distances, but often hitchhike on other moving objects.
Usually the damage to plants caused by earwigs is minor, unless their populations are high. As earwigs hide in cool, moist places during the day and feed at night, good housekeeping practices in the yard and garden can go a long way in reducing populations of earwigs. Here a few simple tips for prevention.
– Clean up garden debris and organic mulches, especially around foundations, since these moist areas serve as daytime hiding spots for earwigs.
– Spread dry gravel as mulch next to foundations.
– Earwigs are attracted to lights, so eliminate or reduce lighting around foundations.
– Remove leaf litter, large stones, dead wood, wood piles, and mulches.
– Keep shrubs neatly trimmed to allow for light penetration and air circulation, especially near the base of the shrub.
– Discourage and reduce entry into buildings by caulking and repairing, cracks and crevices, and checking door thresholds, windows and screens for a tight fit. 

Although you may be disgusted by earwigs, remember they are considered beneficial insects so they should only be treated as pests when their damage becomes excessive. Homemade trapping mechanisms are most effective and can be achieved with various methods that provide a dark, damp hiding place. You can make traps from slightly damp, rolled-up newspapers, cardboard tubing or cardboard filled with straw or crumpled newspaper, taped shut at one end; damp cardboard boxes, like cereal or shoe boxes, turned open side down or with holes cut in the sides and the lids intact or tuna cans with one centimetre of oil, preferably fish oil, but any type of edible oil will work (vegetable, safflower, olive, etc.) or beer and sink them into the ground near plants. Whatever trapping method you choose make sure to empty them every day. Put trapped earwigs in a pail of hot soapy water to kill them and then dispose of them in a sealed container in the garbage.
Hopefully you have a new appreciation for the benefits that earwigs can provide to a garden and not just the negative side of this insect. If you still need to get rid of them, then I hope the tips provided are useful for you.