Banded Ash Borer (Neoclytus caprea),
Readheaded Ash Borer (Neoclytus acuminatus)
Solomon, J.D.; Leininger, T.D.; Wilson, A.D.; Anderson, R.L.; Thompson, L.C.; McCracken, F.I. 1993. Ash pests: A guide to major insects, diseases, air pollution injury and chemical injury. Gen. Tech. Rep. SO-96. New Orleans, LA: U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station. 45 p.
These borers infest weakened, dying, and recently dead ash trees, but are most destructive to recently cut sawlogs. They occur throughout most of the United States, but are most common in the East.
Identifying the Insects
Adults of both species are elongate, tapered in form, and vary from 4 to 18 mm in length. The redheaded ash borer is reddish with yellow bands; the banded ash borer is black with yellowish-white bands. Larvae of both species are creamy white, short, robust, and 10 to 22 mm long.
Identifying the Injury
Round adult exit holes in the bark and wood and mines under the bark are evidence of infestation. The principal injury is from larval tunnels in the sapwood; the oval tunnels are tightly packed with frass. Injury to recently felled trees and logs is often confined to the shaded bottom half.
Adults of the redheaded ash borer emerge from May to August in the North and from February to November in the South. Eggs, deposited under the bark, hatch in 1 week. Larvae penetrate the sapwood to feed and overwinter in their tunnels. There are two to three generations per year in the South and one to two in the North. The banded ash borer has one generation per year.
Keeping ornamentals healthy will help prevent infestation. Sawlogs may become infested within 20 days of felling during the summer and must be processed promptly