I wish that I could offer you a quick fix. Unfortunately, borers (the larvae of the Clearwing Moth) are tough to control because they burrow beneath the bark of
trees, making the inaccessible to most chemical applications. The moths lay their eggs primarily on
trees which suffer from some sort of stress. The tunnels which the newly hatched larvae create as they burrow and eat disrupt the flow of nutrients and water to the trunk and branches, weakening them and possibly killing the entire
tree.
Keep your
trees well watered and fed, and remove and destroy affected branches.
You may be well advised to contact a certified arborist or
tree service regarding the removal of the dead
trees. He can also offer suggestions regarding the use of
parasitic wasps and beneficial nematodes in your garden to control borers and
many other harmful insects. [ August 25, 2002: Message edited by: Bill ]