Box elder bugs are a nuisance insect. In early fall these insects will attempt to enter your home for protection. Prevention includes caulking , weather strip and sealing up all cracks and entry points around your house foundation, vent openings, windows and doorways to prevent these critters from coming indoors. We do not recommend insecticides indoors. You can use a shop vac indoors and drown in soapy water or vacuum up the bugs and dispose of the bag.
Outdoors the insects can be knocked down with a forceful spray of soapy water. If plants are nearby you may want to use insecticidal soap. The most efficient control can be obtained in October when the population is concentrated on the trunks of boxelder trees near the ground. For more information see our Box Elder publication
https://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG10_Boxelder_Bug.p...
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