These bugs are about ½ inch long and are brownish black with red markings on the thorax and wings. The immature stages are colored red with reduced wings. Earwigs are commonly found on trees in the maple family, and are numerous where boxelder trees grow. They often gather in large numbers in the fall.

(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.