Earwigs are second only to slugs and snails in crop destruction.
Members of the order Dermaptera, the earwig most commonly found in California is the European earwig (Forficula auricularia). Earwigs were introduced accidentally in the early 1900’s. The word Dermaptera comes from Greek words that mean ‘skin wing’. Contrary to the old wive’s tale that claims earwigs lay their eggs in human ears, which is not true, the name actually comes from the uniquely ear-shaped hindwings, which are rarely used.
Earwigs are easily recognized by their pinchers, or forceps, on the back end. You can tell the gender of an earwig by the shape of these pinchers. Males have curved pinchers, while female pinchers are straight. While they generally don’t bite, they can and will if they get caught in your clothing or hair. Mature earwigs average 3/4” in length.
Protected from sunlight and heat in a dark, moist place during the day, earwigs emerge at night to hunt and feed.
On one hand, earwigs are beneficial insects because they eat aphids, mites and other insects. On the other hand, earwigs are serious pests, especially in the spring. Earwigs can decimate young seedlings in a single night and cause serious damage to soft fruits such as figs, peaches, nectarines and berries. Earwigs can also damage many flowers, including zinnias, marigolds, and dahlias.
It is relatively easy to trap earwigs using a moistened, tightly rolled up newspaper. Earwigs will seek out the cool, damp sanctuary in the predawn and you can simply toss them in a plastic bag and put them in the trash or feed them to your chickens. Another simple trap consists of an empty tunafish can with 1/2” of oil or bacon grease in the bottom. Soy sauce can be added for even better effectiveness. Sink the tins near fences, walls and large shrubs, to ground level. The earwigs will drown themselves.
Earwigs prefer a more moist environment than our normal California summers, so limiting access to moisture is another way to reduce earwig populations. Pesticides are generally ineffective against earwigs.
You can grow a surprising amount of food in your own yard. Ask me how!