Boxelder bugs are black with thin red lines in adults, full red in its young.
The prime host of these insects are the boxelder tree, although they also feed on maples, almond fruits, and apples, strawberries, prunes, pears and other fruit.
Adults leave their overwintering sites between March and April, where mating and egg-laying takes place. Adults often become gregarious and assemble on the south sides of trees, rocks, and buildings to warm themselves in the sun. After large masses of bugs accumulate, they tend to fly to nearby buildings or other protected sites where they hibernate for the winter, usually within the walls, if a structure is involved. Adults are capable of flying up to two miles from their original congregation site.
During the winter months, individuals or small parties of boxelder bugs foray inside houses and fly into windows, bathtubs and sinks and congregate on the floor. Normally this occurs on the south and west side of the house, during sunny weather.