In many areas of the country when cool, fall days arrive, Asian lady beetles (ladybugs), Harmonia axyridis, and boxelder bugs, Boisea trivittatus, congregate on exterior walls. They typically choose the south and west facing walls since these walls are the warmest. Once on the wall they look for nooks, crannies and other dark openings where they can hibernate over the winter. Log checks, gaps between butt joints and corner openings provide ideal wintering sites for these insects. If any opening leads to the inside of the home, they can become a real nuisance, especially if they enter in large numbers. An effective method to handle them inside is with a vacuum cleaner. Spraying them with pesticides is unnecessary and unhealthy.
The best way to keep them out of your home is to block their entry points with a sealant, screening and weather stripping. Using high quality sealants like Energy Seal™ or Woodsman™ will help prevent these and other insects from entering your home for years to come. When sealing, pay special attention to window and door frames. That's where openings typically appear as a home settles and logs season.
Although ladybugs and boxelder bugs do no damage or reproduce indoors, they can still be a nuisance. If a gathering of insects on the exterior walls of your home bothers you, spray them with a simple solution of soap or detergent and water. To help keep them off of the walls, you can use a pesticide containing deltamethrin, cypermethrin, permethrin or bifenthrin. These products only last about three to four weeks, so the treatment will have to be repeated every so often and should only be used during periods of peak activity. Be sure to follow label directions and read and understand all precautions that must be taken when using any pesticide.
Most pest control companies offer some type of exterior treatment for these insects as well. But be aware that any type of exterior treatment must be applied before the insects enter the home in the fall of the year.
