Boxelder Beetle

Asked April 21, 2019, 10:58 AM EDT

How to destroy these beetles, so that we can enjoy our backyard this year? Last year we moved to Josephine County, Oregon, and became inundated with these creatures. They land on everything humans animals food drink books magazines anything we take outside to enjoy our backyard area. Any tips would be greatly appreciated. Thank you very much. Lori R.M.

Josephine County Oregon box elder bugs nuisance insect

1 Response

Western box elder bugs, Boisea rubrolineata, are well-known, and often widely cursed, nuisance insects. The seeds of boxelder and other maple trees are their primary food source.

In the fall, the insects move to places to survive the winter. Prime choices are light-colored structures which are 2 or more stories high.

The bad news is that it's unlikely you can get rid of them because new generations will repeat this process year after year. The good news is that you have a chance to decrease the numbers during each year.

Here’s how it goes:

In the fall, the insects gather on sunny exterior walls, usually the south or southwest side. As temperatures drop, most people think they "go away." But, no. The insects have simply moved into the wall void.

Once in the void, they mark the interior of that space as a signal for next year's generation that it's a good shelter during cold weather.

Management of boxelder bugs is aimed at blocking their access to the interior of human structures, be that garages, workshops, and homes.

It's helpful to caulk and seal indoor cracks and crevices during the fall and winter. But wait until July or so to do the same to exterior cracks and crevices.

Boxelder bugs tend to be creatures of habit in that they tend to gather at the same date each year. Mark the date on your calendar so that you can contact a pest control before their arrival next year, to request they spray about a week prior to the bugs’ expected arrival. In most cases, the product is a repellent.

Further, ensure that window screens are intact. And consider installing weather stripping around doors and windows.

Then, too, a wet-dry shop vac is a handy disposal tool when the insects are especially numerous.

For a summary of boxelder life, habits, and management, see "Boxelder Bug - Nuisance Management for Homeowners" - https://www.cals.uidaho.edu/edcomm/pdf/CIS/CIS1155.pdf. Please note that contrary to the suggestion in this and other publications, removing nearby boxelder trees seldom resolves the problem because the bugs may fly in from quite a distance.