Boxelder Bugs (Maple Bugs) Invade Homes in Fall


Visitors: 521

Boxelder bugs, sometimes called maple bugs, are relatively large insects, about 1/2” long, dark gray in color with red markings on their backs. The bugs are harmless. What makes them remarkable is their tendency to congregate on certain houses in the fall of the year, often in enormous numbers. It truly seems like an invasion - especially the first time it happens.

Here's what's going on. Boxelder bugs (see a color image at have one generation a year. Eggs are laid in early summer on maple trees (boxelder is a type of maple). Eggs hatch and the young nymphs feed on maple tree leaves during the summer. They do no apparent harm to the trees. The insects reach adulthood in fall and can fly. Adults abandon the trees on which they developed in search of a place to “overwinter”. Many insects overwinter. It is not really a state of hibernation, or diapause, but rather simply an inactive stage brought on by low temperature. Once warmed the insects resume activity. Insects seek protected places in which to overwinter.

Fall migrating boxelder bugs are attracted to large trees with dense, evergreen foliage like cedars. Trees with deeply fissured bark also are selected. Both must appear to be good overwintering sites. A single large tree might attract hundreds, or thousands, of boxelder bugs from the surrounding area. These bugs are strong fliers so may travel miles from the maple tree on which they developed. We now have a large tree with perhaps thousands of overwintering boxelder bugs - so far so good.

Let's put this tree, full of bugs, near the sunny, southwest side of a house. When the house siding heats up during the day all of a sudden the nice warm house seems like a better place to overwinter than the tree. Presto, the bugs move en mass to the house. Imagine, a thousand, or more (seems like millions!), 1/2” bugs congregating on the outside of your house, around doors, windows and on siding. This actually happens to many people each fall, year after year.

What to do. First realize that these bugs are harmless. They don't bite or sting, won't hurt your house nor will they set up permanent residence. But even people who know all this freak out when confronted with all these bugs. Here are some suggestions. The most important thing is to prevent the bugs from getting indoors. If they do gain entry they will likely be around until spring. Repair window screens, caulk cracks around window and door frames and screen soffit vents.

Next, wash down aggregating masses of bugs with water spray from a garden hose then clean the siding with soapy water from a hose-end sprayer. A weak solution of laundry detergent is fine for this application. There is some evidence that washing the siding helps to discourage other bugs from congregating. Don't use insecticidal sprays. Insecticides don't work well on these semi-dormant insects and can be messy and dangerous. You may need to repeat this procedure every few days until the number of new bugs starts to drop.

On occasion large numbers of bugs will get into the attic or exterior wall voids of a house. Again, these insects cause no real harm but may be a nuisance. They will find a way into the home's interior on warm winter days - probably the day of your dinner party. In this case it may be necessary to treat the attic and walls with insecticidal dust. Bugs found crawling around indoors should be removed with a vacuum cleaner. Don't reach for the can of insecticide!

You may have concluded that the solution to this invasion problem is to remove the big tree. Sometimes this works but sometimes it does not. Sometimes the big tree is in your neighbor's yard. Good luck!

Find related information at Information about insecticidal dusts can be found at

copyright 2005

Jack DeAngelis, PhD


Article Source:

Rate this Article: 
Bed Bugs
Rated 4 / 5
based on 5 votes

Related Articles:

Landlords vs Tenants - Who Pays When Bed Bugs Invade?

by: Douglas Stern (October 02, 2008) 
(Real Estate/Property Management)

House Bugs - How To Get Rid Of Bugs And Stop Them From Ruining Your Home

by: Katie Johnson (February 02, 2008) 
(Home Improvement/Cleaning Tips and Tools)

Good Bugs Bad Bugs

by: Ena Clewes (December 27, 2007) 
(Home and Family/Gardening)

Moths to Bugs, Bugs to Viruses, What Next? Computer Viruses and Anti Virus ..

by: Lisa Carey (February 25, 2008) 
(Computers and Technology/Personal Tech)

Quick Facts About Bed Bugs - Signs Bed Bugs Might Be Infesting Your Home

by: Pleaman Haggett (March 17, 2008) 
(Home Improvement/Pest Control)

How To Get Rid Of Bed Bugs – Call A Bed Bugs NJ Exterminator

by: Prakash Mondal (October 19, 2012) 
(Home Improvement/Pest Control)

Bed Bugs Alert - Know the Bed Bugs Symptoms

by: Roger Mitchell (December 05, 2007) 
(Health and Fitness/Home Health Care)

How to Get Rid of Bed Bugs - Learn How To Get Rid Of Bed Bugs With Ease!

by: Christopher Luke Jones (August 02, 2007) 
(Home and Family)

How To Get Rid Of Bed Bugs: Get Rid Of Bed Bugs Quick

by: Emma Drosy (September 27, 2006) 
(Health and Fitness)

Bed Bugs

by: Eve Garcia (October 26, 2010) 
(Home Improvement/Pest Control)