Adults are long (about 1/2 inch), oval shaped, black with red "trim," and have prominent antennae. These are true bugs with piercing-sucking mouthparts for feeding on their primary host, the fruit of the boxelder tree. Although specialized on boxelders (a member of the maple family), these bugs will also feed on silver maples and occasionally the fruits of other trees. Boxelder bugs often invade homes, seeking shelter from the onset of cold weather. They congregate on the south side of structures, and if there is a way in, they will enter.

Boxelder bugs overwinter as adults in the northeastern United States and emerge in spring to begin reproduction. Eggs are laid throughout the landscape, but especially in grooves on the bark of boxelders. Like other true bugs, they go through 5 nymph stages. In the southern United States, there may be 2 generations; but in the north, there is only 1

Damage from boxelder bugs is mainly aesthetic people do not want to see them inside their homes. Because they may enter in large numbers, some type of control may be needed. The fecal droppings of boxelder bugs may stain fabrics and wallpaper. They release a disagreeable odor when handled roughly and can potentially bite, although the bite is minimal.