Up to 1/2-inch long.
Ranges from gray to black with red criss-crossing stripes on the wings. Nymphs have bright red abdomens.
A number of insects have discovered that heated buildings are ideal for surviving the cold of winter. Such pests include box elder bugs, cluster flies, and lady beetles. As the weather cools in late summer and early fall, the sun warms the southern and western walls of buildings. The warmth attracts these insects to buildings where they crawl inside cracks and stay there for the winter. This would be fine, but during warm winter days, some insects “wake up” and end up on the inside of the building.
Box elder bugs feed on maple and box elder trees and usually infest buildings where these types of trees are nearby.
The best way to control such pests is by prevention as described below. If it’s too late and they are already inside, it takes a professional to find and treat the right areas to minimize the numbers of pests seen inside. If your home has experienced a problem with overwintering pests, take the following steps next summer to prevent a recurrence: