Boxelder bug
Boxelder bug
Close up image of Boxelder bugs
Colony of Boxelder bugs
Boxelder bugs on trees
swarm of Boxelder bugs
Swarm of Boxelder bugs

Boxelder bugs go unnoticed for most of the gardening season. They spend summer feeding on leaves and seeds in female boxelder trees. But when fall approaches, they trade trees for buildings and seek out places to overwinter. Late summer and fall finds swarms of these nuisance pests covering home foundations and crawling through cracks and crevices to reach walls and crawl spaces indoors. Hot, dry summers bode well for boxelder bugs, but not for nearby homeowners.

Boxelder Identification: Adult boxelder bugs are black, 1/2-inch-long insects with distinctive red-orange margins on their wings. Three red-orange stripes run lengthwise on the small area right behind their heads. Immature, wingless boxelder nymphs measure about 1/16 inch in length. Predominately bright red, although they change color as they age. During summer, you'll find all life stages of the bug present at the same time.

Signs/Damage of Boxelders: Boxelder bugs have piercing mouthparts that suck out plant juices, but healthy trees and plants sustain very little damage. Unlike Asian multicolored lady beetles, these home-invading pests rarely bite humans. However, they emit a very unpleasant odor when crushed or sucked up in a vacuum when they emerge indoors on warm winter days. They also leave excrement stains on walls and window coverings.

How to Control Boxelders: Effective boxelder control means stopping these pests before they get indoors. Clear your foundation of hiding places, such as leaf debris, and seal all potential entry spots.GardenTech® brand offers several highly effective products to kill boxelder bugs by contact and keep protecting for up to three months. These non-staining formulas treat plants, lawns and your home's foundation up to a maximum height of 3 feet:

  • Sevin® Insect Killer Ready to Spray attaches to a common garden hose for easy, thorough coverage of plants, lawns and foundations. There's no need to measure or mix; the ready-to-spray container does that for you as you spray.
  • Sevin® Insect Killer Concentrate provides a simple, economical alternative for extensive coverage of small trees and shrubs, lawn areas and foundations. For maximum results, spray to cover all surfaces thoroughly.

Tip: Boxelder bugs start congregating on the warm southern and western sides of homes in late summer. Treat at the first sign of these pests to kill early arrivals and protect against the swarms to come.

Always read product labels and follow the instructions carefully.

GardenTech is a registered trademark of Gulfstream Home and Garden, Inc.

Sevin is a registered trademark of Tessenderlo Kerley, Inc.


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