Boxelder bugs in Oregon B

Asked April 20, 2017, 1:31 PM EDT

Your website says the bugs live on boxelder trees. We have no Boxelder trees on our rural, Western Oregon forested land. We did have millions of the bugs on our house this spring, which of course caused quite a problem indoors until we sprayed. Do you know the life-cycle of the bugs? What trees would they be living on here?

Washington County Oregon insect issues boxelder bugs

1 Response

Boxelder trees and other maples are the primary hosts for Western boxelder bugs (Boisea rubrolineata) but these insects may also be on fruit trees, goldenrain trees, and sometimes grass, alfalfa, and potatoes.

The cause for concern with boxelder bugs is their major nuisance value here in the Willamette Valley. They typically congregate on the exterior of a south or west-facing wall of light-colored, multi-story buildings from fall though spring, and will sometimes come indoors. When temperatures drop, they seem to disappear but that’s because they have moved into the wall void where it is warm and dry.

A vacuum can be used to collect modest quantities, whereas a wet-dry shop vac can dispatch larger quantities. If some come indoors, flick them into soapy water or use the vacuum.

To keep the bugs out of your indoor spaces, block their way. During the fall and winter install or replace weather-stripping, and caulk or seal interior cracks and crevices around windows and light fixtures where they might enter your house. But, to avoid sealing the bugs in the wall void, wait until July to seal cracks and crevices on the exterior of the structure.

Because box elders return every year on or about the same date, consider hiring a pest control company to spray a repellent pesticide on the exterior wall where they gather about a week prior to the bugs’ expected return.

- “Managing Boxelder Bugs around Your Home” http://extension.uidaho.edu/clearwater/files/2014/10/Managing-Boxelder-Bugs-around-Your-Home.pdf

- Western Boxelder Bug http://bugguide.net/node/view/15578

- Nuisance and household pests - Boxelder bug https://pnwhandbooks.org/insect/structural-health/nuisance-household/nuisance-household-boxelder-bug