Boxelder Bugs

Boxelder bugs are a common seasonal nuisance pest in Michigan, especially during the fall. While they do not bite, sting, or reproduce indoors, they often gather in large numbers on the exterior of homes and may find their way inside. Effective control focuses on exterior prevention rather than interior treatments.

Boxelder Bugs

Overview
Boxelder bugs are most noticeable in late summer and fall as they seek warm surfaces and protected areas to overwinter.

Behavior
They congregate on sun-exposed exterior walls, siding, and windows, particularly on the south and west sides of homes. As temperatures drop, they enter through small gaps and openings to shelter indoors.

How to Identify Them
Boxelder bugs are black with distinct red or orange markings on their wings and thorax. They are commonly found in groups rather than individually.

Why They’re a Pest
Although harmless, boxelder bugs can appear in large numbers and become a major nuisance. When crushed, they can emit an odor and may leave stains on walls, curtains, and surfaces.

Common Boxelder Bug Entry Points

Overview
Boxelder bugs rely on small exterior openings to access homes, often entering unnoticed until activity is seen indoors.

Behavior
They crawl into cracks and voids and remain hidden during colder months, reappearing on warm days.

How to Identify Entry Areas
Common entry points include:

• Gaps around windows and door frames

• Siding seams and exterior trim joints

• Soffits, fascia, and attic vents

• Utility penetrations and foundation cracks

Why Entry Points Matter
Without addressing these access points, boxelder bugs will continue to return seasonally. Preventative exterior treatments combined with sealing gaps are the most effective approach.

Why Interior Treatments Aren’t Effective

Overview
Interior treatments are often requested but rarely provide meaningful control for boxelder bugs.

Behavior
Boxelder bugs do not nest or reproduce indoors and often remain hidden in wall voids beyond the reach of treatments.

How Control Is Commonly Misapplied
Spraying inside typically kills only visible insects and does not prevent new bugs from entering.

Why Exterior Prevention Works Best
Exterior perimeter treatments and exclusion stop boxelder bugs before they enter the home, reducing indoor sightings without unnecessary indoor pesticide use.

Seeing Boxelder Bugs Indoors?

Seasonal pests like boxelder bugs require a preventative approach. If you’re seeing recurring activity or want to reduce fall infestations, use the contact form and we’ll explain the best options for your home.