(Boisea trivittata) The adults and immature stages feed on the seeds and
stems of boxelder and other maple trees. There is usually one generation
per year, and the adults (and sometimes large nymphs) overwinter in masses
in protected locations around the outside of structures. Sometimes adults
will enter houses in small to large numbers. They do not bite but may stain
fabric and carpet if crushed.
Removing boxelder or other maple trees is not recommended, since these
insects may find food at other locations and overwinter at houses without
the trees nearby. Disrupting the masses of bugs in the fall, and perhaps
spraying with insecticide will help to reduce overwintering populations.