Boxelder bugs in the house
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URBANA -- Fall's arrival
also signals the return of a pest that invades homes, seeking warm
lodgings for the winter, said Sharon Yiesla, a University of
Illinois Extension horticulture educator based in Lake County.
"We may start to notice these bugs in
our homes," said Yiesla. "They are boxelders, and the adult boxelder
bugs are flattened, oval insects, about a half-inch long. They are
dark brown to black in color with red markings on their backs. The
nymphs (young) are smaller than the adults and are bright red with
small, partially formed wings. These small wings look like dark
During the growing season, boxelder
bugs feed primarily on the box elder tree (Acer negundo), sucking
sap from the leaves and seeds. The damage done to trees is
relatively minor, but boxelder bugs are annoying as a household
"In the fall, as temperatures begin to
drop, the insects migrate to homes," said Yiesla. "They can often be
found clustered on the outside of the house, especially on the south
and west sides, where the sun warms the building.
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"Eventually they crawl into cracks and
crevices and enter the home. These insects do no real damage in the
home; they are merely a nuisance. They do not feed or reproduce
inside the home; they enter only for protection against winter."
Yielsa noted that the easiest method of
control is removal using a vacuum cleaner. The bugs should be swept
up and the vacuum cleaner bag should be discarded. Do not crush the
insects, as they can leave a red stain behind. Caulk cracks and
crevices around windows and doors to limit entry into the home.
[University of Illinois news