B-1050

Hardwood borers can cause die-back of affected stems or can weaken them so that they break off. The larvae chew into the branches and bore tunnels several inches long, and females lay eggs on the bark of lilac, ash, and privet. Stress and freshly pruned plants are most susceptible to these kinds of attacks.

Management of hardwood borers of trunks and large branches explains the body form and life history of the lilac and ash borer. The three-page bulletin lists the effects the borers have on plants and outlines management practices that help lilac and ash plants fight infestations.

 “Infestation is most likely when host trees or shrubs are stressed or unhealthy,” the authors state. “Management to improve and sustain plant health will reduce infestation and often allow the plant to tolerate some borer activity.”