Boxelder Bugs are black 1/2 inch long with red or orange markings and 3 stripes in the back. the nymphs are 1 1/16 inch and are red when they hatch. Boxelder bugs are insects well know by people, they will go un-noticed in the summer time but it will be a issue in the fall when they are trying to come inside your home. they a nusiance beacuse they can enter your home in large number, they do not bite. but because of the quantity coming in they made stain your window sill and blinds with the droppings.(excrement) what do they eat? boxelders emerge from wintersite in the spring and feed on low vegetation and seed on the ground. they mate after two weeks of feeding and move to female seed-bearing boxelder tree. they can also feed on ash or maple trees.