Box Elder Bugs
Description: Adult box elder bugs are ½-inch long and brown-black with three red stripes on the thorax and red veins in the wings.
Biology: The adults overwinter in dry, protected locations, emerging in the spring to lay small, red eggs in the cracks and crevices in the bark of box elder trees. The nymphs hatch in approximately two weeks when new leaves appear. The young bugs suck the juice out of the tree leaves and twigs with their piercing-sucking mouthparts. They molt five times before becoming adults. In warm climates, these bugs have two generations per year.
Habits: They prefer to feed on the leaves, twigs, and seeds of female Box Elder trees and also on Maple, Ash, and the young fruit of grapes, apples, and plums. Box Elder Bugs do little apparent damage to the box elder tree; they just become a nuisance around structures when they attempt to enter to find overwintering sites. Their migration begins in the autumn when they congregate on the south side of structures, rocks, and trees in areas warmed by the sun. They then may fly to an adjacent building, enter it, and hibernate for the winter. Indoors, their droppings stain drapes, curtains furniture, sheers, and other materials where they rest. If handled, Box Elder Bugs can bite, and when crushed, they emit a strong disagreeable odor.