boxelder bug infestation

Asked March 22, 2019, 5:58 PM EDT

We live in the foot hills of the Coast Range. Above the Casino. (Spirit Mountain) Have lived here 28 years. It's only been the last few years that we have had the problem with the Boxelder's. This last summer / fall has been the worst. The siding on our house is cedar shingles, probably the worst scenario. There were millions, the whole wall was black. They were crawling under the shingles. When this would happen I would get the pressure washer out and use it to wash them away and wash under the shingles. They have found ways to enter the house through the winter. We have the Shark cordless vacuum beside us at all time. We have oak, maple, and some fruit trees close to the house. I have tried to find them in the trees but have never seen them. Will the nest in any of these trees? How far will they travel? Can I start spraying this spring around the house and trees to try and eliminate the bugs and what would be the best spray to use? I did look at a couple of sites on the internet. One site recommended Lambda Star UltraCap 9.7 to spray the side of the house and around trees. I will wait to hear from you regarding the problem. Thank you Larry Ediger

Polk County Oregon

1 Response


Repeated vacuuming is what we usually advise with nuisance insects like box elder bugs. As you may know this species doesn't feed on people, pets, homes or furnishings but just tends to cluster on buildings and trees and be an annoyance. Just continue vacuuming them up until they are gone. Then, try to find out where they got in and seal them out.

At this time OSU Extension doesn't have a recommendation for pesticides, biocontrols or the like for controling these insects.

If you have a wet/dry shop vac you can put some soapy water inside to drown the insects and reduce the chances that some might get out of the trash or wherever you dump them.

You can read more about how to deal with box elder bugs and similar creatures here:

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