Boxelder Bug

Commonly found near boxelder trees (Acer negundo), but also maples and ash trees. They often overwinter in sheltered locations such as in homes, under bark, or in leaf litter.

Primarily feed on the sap of boxelder trees, and sometimes other maple and ash trees, by piercing leaves, seeds, and soft new shoots with their sucking mouthparts. Occasionally, they may feed on fruits.

Boxelder bugs are gregarious and often aggregate in large numbers on the sunny sides of buildings and trees, especially in fall before seeking overwintering sites. They tend to enter homes through cracks and crevices to seek shelter from cold weather. They are active during the day.

Generally considered a nuisance pest, especially when they enter homes in large numbers. They do not bite people, transmit diseases, or cause structural damage. However, when crushed, they can emit a foul odor and may stain carpets, curtains, and other materials with their fecal droppings. They offer little direct benefit to the ecosystem.