How To Get Rid Of Boxelder Bugs
Boxelder Bug Information & Prevention
Boxelder Bug Identification
Boxelder bugs are common pests over much of the United States.
Adults are about 1/2 inch long. They are bright orange, red or black with narrow reddish lines on the back.
Boxelder bugs feed principally by sucking juices from the box elder tree but are sometimes found on other plants (especially maple trees). They do very little damage to the trees they attack, but they can become a nuisance at certain times of the year. Boxelder bugs develop by gradual metamorphosis, from egg to nymph, then to adult.
When box elder bugs build up to large populations and invade a home, they are usually pests only by their presence. However, their piercing-sucking mouthparts can sometimes puncture the skin, causing slight irritation. Sometimes, they leave fecal material that may stain resting sites such as curtains. They may be seen to gather around the foundations, bases of trees, along foundational walls and fence rows during the fall months. They are part of a group of insects called "fall invaders," which are occasional invaders.
Adult boxelder bugs will enter structures into the fall, seeking winter shelter.
Boxelder bugs enter structures in the fall months and "overwinter" in protected areas. They seek shelter in protected places such as houses and other buildings, cracks or crevices in walls, wall voids, attics, doors, under windows, and around foundations, particularly on the south and west exposures. Boxelder bugs can come out even during the dead of winter when it is cold outside, and the sun is shining.
They will then emerge in the spring to seek out host trees to feed and lay eggs.
How To Get Rid Of Boxelder Bugs
Prevention-Key to Boxelder Bug Control
- Prevention is key to getting rid of boxelder bugs. Spray the exterior walls of your home in the fall with a residual insecticide to stop them from over-wintering if you have not sprayed earlier. If you treat earlier (early summer months), you have the best chance to control the immature stages of boxelder bugs. Ideally, spray twice, once in the spring-early summer months when they emerge and once in the fall when they seek shelter. Once they have come inside to overwinter, total control is nearly impossible as locating all infested voids is difficult.
- If your home has a prior history of boxelder bugs, find and seal as many exterior cracks as possible during the summer.
- The easiest way to remove boxelder bugs once they are indoors is a vacuum cleaner.
- You can also use an insecticide spray around the baseboards and window seals on the home's interior to further control the bugs. Interior spray should be the last line of defense, however, because it won't stop the bugs from coming into the home. The boxelder bug will eventually die after it comes into contact with the insecticide.
Recommended Residual Insecticides For Boxelder Bug Control
To help prevent box elder bugs, cluster flies, ladybugs, and similar pests from entering in the fall, spray fast-acting synthetic pyrethroids such as the ones listed below on the structure's exterior walls. Spray around eaves, attic vents, windows, doors, under-fascia lips, soffits, siding (including under lips), and any other possible points of entry, concentrating on the south and the southwest sides. It is also helpful to spray around the perimeter. Shady areas are less likely to attract box elder bugs. Spray Bifen It or Avesta CS around the perimeter outside. Avesta CS may also be sprayed on the inside.
Key Takeaway
To prevent Boxelder Bugs from entering your home in the fall, treat the outside perimeter with a good all-purpose concentrate.
Pay particular attention to the south and west exposure of the house.
Mechanical means of exclusion
Exclude Boxelder bugs during the summer months. Concentrate on the south and west exterior walls. Avoid excluding them during the months when they are most likely inside to not seal them inside. If you seal them inside, they may enter interior rooms in large numbers.
- Plug weep holes with wire mesh.
- Foundation and attic vents should be equipped with tight-fitting screens
- Fix broken window screens and door jams
- Plug cracks in the foundation or roof with exclusion materials
- Caulk cracks and caulk around utility lines
Written by our resident pest control expert Ken Martin.
Written by our resident pest control expert Ken Martin.