Boxelder bug population appears to be flourishing
By Kyle Vuille
Ranger-Review Staff Writer
Fall has officially begun and typical of the season, residents of Glendive are seeing swarms of boxelder bugs out, around, and in their houses and are desperately trying to keep them at bay. This year, though there are no real hard numbers, boxelder bugs seem to be more of a nuisance than usual.
“It must have been a good year,” MSU Extension Agent Bruce Smith said. “It’s the most (boxelder bugs) I’ve seen in awhile.”
The western boxelder bugs usually start producing their eggs in July and stop around September on the seeds of female boxelder trees. The western boxelder bugs mostly reside in the states of Montana, Idaho, Washington, Oregon, Nevada, Arizona and California.
Boxelder bugs feed off the seeds of female boxelder trees as well as maple trees and ash trees on rare occasions.
According to Montana State University insect diagnostician Laurie Kerzicnik, the summer weather can affect the boxelder bug population in the fall.
“We do have more of an issue (with boxelder bug production) during a hot, dry summer,” Kerzicnik said.
The production of the eggs and life span of the bugs depends on the amount of the host tree’s seeds and the growing season of the boxelder trees.
The issue that arises this time of year is the red and black insects try to make their way into the warmth of homes.
During the fall, the bugs find refuge on the south or southwest sides of buildings or anywhere where they can retain heat.
Once the insect can’t take the cold outside, they make their way into homes by way of dryer vents, cable holes and cracks in the ceiling and windows.
Kerzicnik said the best way to stop a home invasion is to seal any openings and use spot treatments where you see congregations of the insect.
Smith said once the bugs have made their way into the home, he recommends sucking them up with a vacuum and immediately emptying the bag before the bugs have a chance to escape.
“Once they’re in the house, they’re in a dormant state,” Kerzicnik said. “They’re not reproducing and they don’t feed on anything in the house.”
If the bugs find a place inside to remain dormant through the winter, they will appear again when the weather warms up in the spring.
Kerzicnik added the bugs are not poisonous, but what makes them a nuisance is when the bugs are squished, their internal contents leave stains on fabrics like curtains and other household upholstery. Kerzicnik also said the insects can bite, but that is extremely rare.
Local pest control agent Alex Rivas, of Ecolab, said between Glendive and Wibaux, he gets about 30 to 40 calls about the boxelders in October alone.
“Usually early spring, late summer and early fall, you see a hike in calls about them,” Rivas said.
Reach Kyle Vuille at