What symptoms does a tree infested with the borer exhibit?
Infested trees exhibit top-down dieback typical of other phloem borers such as two-lined chestnut borer. It has been observed that one-third to one-half of the branches may die in one year. Most of the canopy will be dead in two years. Affected trees may have vertical splits in the bark 2-4 inches long. Often dense sprouting of shoots can been found arising from the trunk or roots. Although difficult to see, the adult beetles make a “D”-shaped exit hole in the bark, roughly 1/16 inch in diameter.
