Fact Sheet – IP1

Earwigs

1100 W. Moana Ln., Reno, NV 89509 11301 So. Virginia St., Reno, NV 89511

Key Points:

· Earwigs don’t do as much damage as they are blamed for.

· Earwigs are nocturnal or night feeders, usually hiding during the day.

· Earwigs are comfortable in organic mulches and will feed on critters found in this cool moist environment. They also feed on mites and some species of aphids.

· Earwigs don’t get in your ears.

· Earwigs can be trapped successfully using several methods.

Have you ever eaten an apricot right off the tree? A sun-warmed, glowing orb of velvety smoothness? You close your eyes, sniff that fruity, ripe aroma and take your first juicy bite. Ahh! There's nothing quite like it. And when you open your eyes, what should you behold but an earwig peering back at you (having just emerged from the apricot's stem end, its daytime siesta disturbed by your noisy slurping). Earwigs are nobody's favorite critter. They seem to elicit an uncontrollable urge to smash, stomp, grind, and cut them up by just about everyone. Even seasoned gardeners with a fair amount of live-and-let live blood in them appear to relish killing earwigs. They are the insect everyone loves to hate. It is a proven fact that they can and do damage plants. Yet researchers say earwigs often do far less damage that they are blamed for, and in many cases act as important predators of other arthropods.

Identification

Earwigs are glossy brown, somewhat flattened insects ranging in size from 1/2" to 1" in length. Most youngsters call earwigs “pincher bugs” because of their most distinctive feature -- a rather formidable set of “pinchers” or forceps, extending from the tip of the abdomen. The forceps of males are larger and more distinctly curved than those of females. They are capable of giving you a good pinch and their extremely flexible abdomen allows them to grasp a gardener's fingers with the greatest of ease from any position. Female earwigs use these pinchers to guard their eggs and newly hatched young. The eggs are deposited in clusters underground or in debris. Earwigs overwinter as adults, living under bark, garden debris, rocks, and boards. They have incomplete metamorphosis with nymphs similar to adults in structure and habits. Earwigs may be winged or wingless.

There are twenty-two known species of earwigs in North America, twelve of which have been introduced from the tropics and Europe. The Nevada Division of Agriculture insect collection lists four species of earwigs, three of which - Labidura riparia (Pallas) the dainty ring-legged earwig; Euborellia annulipes (Lucas); and Euborellia cincticolus (Gerstaecker) - are most common in the southern part of the state. Here in northern Nevada, we are blessed with the European earwig Forficula auricularia (L.) which is primarily a garden dweller that sometimes wanders into homes looking for a cool, moist place to live. Introduced into the United States from Europe in 1907, this earwig liked the look of things and settled down to stay.

Earwigs are nocturnal, preferring cool, moist, secluded areas under organic mulch, in crevices, under bark, and in garden debris. Earwigs have chewing mouthparts. They are omnivorous, eating dead and decaying vegetation, soft fruits like strawberries and stone fruits, leaves, petals, and pollen of living plants. They are particularly fond of seedlings and may be found munching on corn silks, causing poor kernel formation. Earwig damage typically consists of small holes in leaves. Whole seedlings may disappear. They chew shallow gouges or holes that extend deep into fruit. Not all the news about earwigs is bad though. A few species are predators of other insects. In commercial orchards the European earwig has been shown to be a useful predator of wooly apple aphid. It is documented that earwigs eat mites, nematodes and insect eggs.

But what you really want to know about earwigs is how to eliminate them, right? Before you begin your war with earwigs, consider taking some time to make sure they are the culprit. They are nocturnal generalists, feeding on any number of things. William and Sheila Oikowski of Bio-Integral Resource Center have observed that in their demonstration garden, earwig damage decreases when planted areas are mulched with some kind of organic-based mulch like bark or straw. Earwigs prefer a cool, moist, biologically active environment such as you would find in a healthy, moist mulch. This complex soil environment provides lots of critters for them to eat. Gardens without organic mulch provide poorer forage for earwigs, forcing them to rely more heavily on vegetation than they would otherwise. The Oikowskis encourage monitoring damaged plants at night, using a flashlight to look for feeding earwigs to determine if they are the source of chewed leaves and damaged flowers. Cutworms, snails, slugs, and other nocturnal garden pests may actually be responsible for the damage you are observing. Keep in mind that earwigs also feed on pollen, aphids, or other arthropods in addition to plant parts.

Where earwigs cause more damage than you are willing to tolerate, it's time to take action. If your garden is not mulched, consider applying mulch around those plants hit hardest by earwigs. A consistent trapping program is a viable way to drop an earwig population down to the point of grudging coexistence. You can take advantage of your superior brainpower and utilize your knowledge of earwig behavior to trap them. They like cool, dark places to spend the day and are commonly found whiling away the heat of the day in flowers. To entice them into traps, give them a cool, dark place in which to crawl. Dampened, rolled-up newspapers (secured with rubber bands) tossed around in the garden and kept moist, damp rags, and short pieces of hose or boards all make excellent "hotels" for earwigs.

Try stuffing damp sphagnum moss into a clay or plastic pot and inverting the whole thing over a stake. Keep the moss damp and earwigs will find it an irresistible abode. Place traps out in the evening and retrieve them in the morning. Shake the earwigs into a bucket of soapy water. You can also use a trap consisting of a tuna can 1/2 filled with vegetable oil and placed near plants ravaged by earwigs. The earwigs are attracted to the oil and meet their maker, unable to exit the can. This does work well.

The word "earwig" comes from the old Anglo-Saxon word “earwiega” which translates to “ear creature.” It is not true that earwigs crawl into your ears intent on boring into your brain! It may be that when people slept on the ground on straw or hay bedding that earwigs would explore slumbering ears as a place to hide.