Lilac Borer

A clearwing moth with brown forewings and clear hind wings that closely resembles a paper wasp in form and behavior, although it cannot sting. Adults emerge in April and May to mate and the females lay their eggs on the rough bark or wounds of ash, lilac, and privet. As soon as they hatch, tiny worms bore into the bark. Most borer infestations occur in the lower portion of the host, from the soil line, up to 3 feet high. Ash trees are commonly attacked when they are small. Structural damage caused by the borers weakens the trees, making them highly susceptible to storm damage. Small, heavily attacked trees can result in total death.