The dogwood borer is one of the most serious pests of flowering dogwood in Connecticut. Very young trees are frequently killed and older ones are left reduced in vitality and with dead and dying branches. Other plants attacked by this insect include flowering cherry, apple, mountain ash, willow and oak.
Injuries also occur at the union of the trunk and branches or smaller twigs and branches.
Young dogwoods are attacked mostly at the crown. The adult dogwood borers are clear-winged moths which begin emerging in late May and may continue to do so until September. They reach their greatest abundance during late June and July. The moths mate and the females lay their eggs on bark, usually near an injury. The eggs hatch and the larvae wander about until they find an opening in the bark, since they cannot chew through uninjured bark.