We know they’re “ugly”… but this is one curious group that is not easily classified as good or bad. Earwigs can be considered either pests or beneficials depending on the situation. They are omnivorous, which means they eat anything. ‘Continue reading’ to learn more.

The common European earwig (Forficula auricularia) was introduced to N. America in the early 1900s. Earwigs serve as predators to help control aphids, caterpillars, and eggs of other insects (GREAT!). They are also scavengers and work as ‘clean-up crew’ to consume dead insects and plant debris (INTERESTING!) However, they are seen as pests when they congregate in homes or feed on live plant tissue including seedlings, flowers, and fruits (NOT SO GREAT!)

Did you know?

Earwigs are the only insect known to demonstrate maternal care of their young. Adult females will rotate their eggs and meticulously clean them to rid or prevent fungi from developing.

Photo by Tom Oates, 2010

Damage can occur if earwig populations are higher than normal. Earwigs feed on developing seedlings, leaves, soft fruits, ornamental flowers, and corn silk (which reduces pollination). A lack of ‘slime’ helps distinguish earwig feeding from slugs or snails. If you are experiencing more earwigs than you’re comfortable with, try these tips:

  • Scout at night to make sure it is earwigs that are causing damage
  • Keep piles of plant debris away from structures, gardens, and nursery stock
  • Remove thick vegetation or ivy from around homes
  • Reducing excessive moisture on the soil surface may help – earwigs tend to seek out damp, dark hiding places

Trapping can be useful to reduce populations: 1. Fill an empty tuna or cat food can or other shallow dish with about 1/4″ of oil. Tuna oil or vegetable oil with bacon grease, etc. They are attracted to the smell, so the ‘stinkier’ the better. 2. Bury the can so that it is even with the soil surface – earwigs will walk into it and be captured. Place traps wherever you are concerned about high activity. 3. Rolled up newspaper or corrugated cardboard placed over moist soil can be attractive as hiding places but will need to be checked and disposed of each morning (adults will be hiding there – gather and place into a sealed bag and dispose of).

More information:

PNW Handbook sections: https://pnwhandbooks.org/insect/hort/landscape/common/landscape-earwig and https://pnwhandbooks.org/insect/tree-fruit/cherry/cherry-earwig

Natural Enemies of Nursery Crops: https://beav.es/3d4

Research on earwigs as predators of pear psylla is being conducted by WSU and OSU’s Dr. Ashley Thompson

**Information and myth-busting video: https://youtu.be/mzPyx-Q_MpI

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