J. D. Solomon, F. I. McCracken, R. L. Anderson, R. Lewis, Jr., F.L. Oliveria, T.H. Filer, and P.J. Barry

Importance – The Oak Timberworm is a major cause of defect and degrade in the red and white oaks in the East. Attacks are most commonly associated with wounds on mature trees.

Identifying the Insects – Adults are brownish black, brentid weevils about 1 to 1.4 inches (25 to 35mm) long. The female has a narrow snout, while the male's mouthparts are broad and flattened. The larvae are white, elongate, cylindrical, and curved.

Identifying the Injury – Attacks usually occur at blazes, around other borer entrances, and other wounds that expose the sapwood. White, powdery frass at egg sites on exposed wood is good evidence of infestation. Winding tunnels .1 inch or smaller (0.2 to 3 mm) in diameter characterize damage in lumber.

Biology – During spring and early summer, females chew cylindrical holes into the sapwood and lay single eggs. Eggs hatch in a few days and the larvae bore almost through the tree then "U-turn" back across the grain to the point of origin. Pupation occurs in the gallery, and adults emerge through circular holes near the egg site. The life cycle requires 2 to 3 years.

Control – Avoid wounds and injuries, including other borer attacks to largely prevent infestation by the oak timberworm.