Oak, hickory, ash, chestnut, maple and cypress can become infested. Beetles sometimes emerge from flooring and furniture several years after they have been placed in a building. Elm borer, Saperda tridentata Olivier Adults are 9 to 14mm long and densely clothed with grayish pubescence. The thorax and wings bear narrow orange stripes on the sides. The wings have three oblique crossbars.
Adults lay eggs in bark of weakened or dying elm trees.
Larvae bore beneath the bark, filling the mines with fibrous frass and completely destroying the inner bark and cambium. Park and shade trees are severely injured, especially old, mature, unhealthy trees. Limbs are attacked first. The thorax is rounded and yellowish with the wing covers either blue or yellowish. Larvae feed beneath the bark of dead oaks and sometimes in stored hemlock bark.