Earwigs abound in wet gardens

CORVALLIS - Are the new, rapidly growing leaves on your perennials being eaten? Is something else eating your strawberries before you do?

If there are no telltale slime trails to indicate a slug problem, your trouble may be earwigs, according to Jack DeAngelis, entomologist with the Oregon State University Extension Service.

Earwigs thrive in the dampness of spring and early summer. One of the most commonly complained about garden pests, earwigs can wreck havoc on vegetable seedlings, soft fruit such as strawberries and young tender perennial leaves. On the other hand, they eat insects and mites that might be garden pests.

Adult earwigs are about three-quarter inch long and reddish brown. They have two pointed tails, known to entomologists as "forceps," trailing out of their tail ends. Though they look a bit scary, they do not bite or sting humans.

Earwig-damaged seedlings are often missing all or parts of their leaves and stems. Older plants often have numerous irregular holes in their leaves, or leaves may be chewed around the edges. Caterpillar damage is quite similar, but caterpillars may leave telltale silky webbing. Earwigs May also feed on corn tassels and blossoms, reducing kernel set.

The University of California Statewide Integrated Pest Management Project recommends several ways to reduce earwig populations without the use of pesticides:

• Get rid of earwig habitat. Earwigs feed at night and seek out cool, moist and shady places such as under boards, debris and clods of dirt during the day. Eliminate refuges such as ivy, weeds, and piles of yard debris and leaves. Keep debris and weeds away from the trunks of fruit trees.
• Encourage natural earwig predators including toads and birds.
• Construct earwig traps out of low-sided, old tuna or pet food cans. Fill the cans with a half inch of vegetable oil. Place several of these traps around the garden. When the cans fill with earwigs, dump out the earwigs and oil and refill. Effective earwig traps can also be made of rolled newspaper or old hose pieces. Place these tubes near plants at sunset. The next morning, go out and shake the earwigs out of the tubes over a bucket of water. Continue the oil and tuna can routine and the newspaper roll or hose trapping every day until you no longer are catching earwigs.