Earwigs are reddish brown with short, leathery forewings and pincers on the tip of the abdomen, and measure about 3/4 inch long. Although they can be pests in their own right, earwigs deserve more widespread recognition as beneficial predators. They help control the common aphid as well as the particular aphid species that attacks apple, plum, pear, spirea, dogwood, flowering crabapple, and flowering quince, among others. While it is true that they may inflict minor damage in the garden, particularly to seedlings, their presence is generally far more beneficial than detrimental.
The earwig's biggest problem seems to be one of image: its scary-looking pincers and a name which derives from an old Anglo Saxon word meaning "ear creature" evoke unfounded fears dating back to old Europe, whence they were first introduced. Nevertheless, while used as a defense mechanism against predators, the pincers are not a menace to people. Furthermore, there is no evidence that earwigs ever crawled into human ears, either merely to hide or to bore menacingly into the human brain! Another image problem stems from sheer numbers: if people see large quantities of earwigs in their gardens, they are likely to attribute to them damage inflicted by other pests. Therefore, conduct a nighttime check with a flashlight to determine if earwigs are indeed responsible for the damage in question before you decide to reduce their numbers.
If earwigs are snacking on the leaf margins of your seedlings, try putting down a mulch of compost. This will provide a complex soil surface with many organisms on which earwigs can feed, and should prevent them from inflicting major damage to your plants. If you have already applied a rich organic mulch and yet still experience problems with earwigs, raise seedlings indoors and transplant them outdoors when they are large enough to sustain some damage. If earwigs are seen eating flowers or larger plants, trap them with containers such as tuna fish cans filled with 1/2 inch of vegetable oil or moistened bread crumbs. Unbaited bamboo tubes or rolled up newspapers are also good traps. Place any of these traps on soil around dusk and check with a flashlight 12 hours later or the following morning. Shake trapped insects into a pail of soapy water to drown them.
Although earwigs don't do any damage inside the home, most people are averse to finding them there. Deny them access by caulking cracks and crevices, screening and weatherstripping doors, pruning foliage that touches the walls of the house, and/or by creating a clean, dry border directly adjacent to the house foundation. Vacuum up stray earwigs found indoors. If earwigs are clustering in damp basements and/or storage areas, consult a homeowner's manual for reducing moisture in these areas. Your earwig problem should dry up, too.