Lilac, ash, mountain ash, and occasionally privet. The base of infested stems are swollen and the bark separates from the wood. A fine sawdust-like material is present around holes in the canes. Pupation occurs in the spring. The moth has clear wings and resembles a wasp in appearance.
Moths deposit eggs in cracks and crevices of bark.
They hatch in 10 to 14 days. Larvae immediately bore into wood. Frass accumulates around holes. Swelling and cracking of the bark are associated with repeated infestations and branches may be severely weakened at the feeding sites. During dry periods in late summer, terminal shoots of infested plants wilt.