Maple Bugs in Manitoba: How to Get Rid of Boxelder Bugs

Few pests are more distinctly Manitoban than the maple bug. Every September, these black-and-red insects appear by the hundreds on sun-warmed siding across the province, and by October, they're finding their way into bedrooms and window sills. Known elsewhere as the boxelder bug, the maple bug is harmless to people and pets, but in the numbers Manitoba sees, 'harmless' doesn't mean 'welcome.'

What are maple bugs, exactly?

Maple bugs are about half an inch long, charcoal black with distinctive red-orange markings along their backs. They feed on the seeds of Manitoba maple trees (also called boxelder), which are everywhere in our river valleys, shelterbelts, and older neighbourhoods: one big reason the province gets such heavy swarms. They don't bite, don't breed indoors, and don't eat anything in your house. Their offence is showing up in overwhelming numbers, and occasionally leaving stains when crushed.

Why they swarm your house every fall

As days shorten, maple bugs start looking for a protected place to spend the winter, and a building beats a tree stump every time. They gather on the warmest surfaces available: south- and west-facing walls that soak up afternoon sun, especially light-coloured siding. From there, they work their way into gaps around window frames, siding edges, soffits, and door thresholds, settling into wall voids to wait out the cold. On warm winter days, some wake up confused and wander into your living space, which is why you find them on windows in February.

Do maple bugs cause damage?

Structurally, no: they don't chew wood, wiring, or fabric. The practical problems are cosmetic and psychological: their droppings can spot curtains and walls, crushed bugs stain surfaces reddish-orange, and sharing a bedroom window with dozens of insects wears thin quickly. Because they release an odour when crushed, squishing them indoors is a bad plan; a vacuum (emptied outside) is the cleaner way to deal with the ones already in.

How to get rid of maple bugs and keep them out

Timing is everything. The effective window is late summer and early fall, before the bugs get inside: sealing gaps around windows, doors, siding, and soffits, combined with a professional exterior treatment on the walls where they gather. Once maple bugs are inside your wall voids for the winter, treatment options shrink: spraying inside walls isn't practical, and you're mostly managing stragglers until spring. That's why an annual fall prevention treatment is the standard approach for homes that get hit hard year after year.

Fortify Pest Control provides exterior maple bug treatments and entry-point sealing across Winnipeg and Manitoba. If your walls turn black and red every September, book your fall prevention treatment before the swarm starts.