Boxelder bugs are the black-and-red shield-shaped insects that swarm sunny exterior walls every fall across Dallas-Fort Worth — and then invade homes by the dozens as temperatures drop. About 1/2 inch long with distinctive red markings along the edges of their dark wings, boxelder bugs gather in massive numbers on warm surfaces, then look for cracks and openings to overwinter inside attics, walls, and around windows. While they don't bite, sting, or damage structures, the sheer number of them — and the staining from their droppings — make them a major nuisance pest.

The name comes from their primary food source: boxelder trees (and other maple, ash, and seed-producing trees). DFW homes with mature boxelder trees, female maples, or ash trees in the yard are guaranteed to deal with annual boxelder bug pressure. Even homes without those trees often get pressure from neighboring properties.

The CanMan's boxelder bug program combines fall perimeter treatment (timed to hit them before they enter the home), tree-targeted treatment when accessible, sealing entry points, and indoor treatment of active clusters. Like stink bugs, prevention is dramatically more effective than treatment after the invasion starts.

Boxelder bugs are present across all of DFW but pressure varies dramatically by neighborhood — driven entirely by tree species. Established neighborhoods with mature boxelder, maple, and ash trees see the heaviest pressure: parts of East Dallas, Lakewood, Highland Park, University Park, older Plano, parts of Fort Worth, and Garland have decades-old boxelder populations. Newer suburbs with younger landscapes see lighter pressure initially, but pressure grows as trees mature. Fall invasions peak in October-November every year. The CanMan times perimeter treatment to catch the migration BEFORE bugs enter homes — dramatically more effective than treating indoor clusters.