Dogwood Twig Borer
ID
444-625
Plants Attacked
Elm, dogwood, viburnum, and many fruit trees.Description of Damage
The larvae tunnel in live twigs and feed down the center of the branch, making a long series of closely placed round holes for the exudation of frass. Periodically, the larvae cut off portions of the twig from within and continue to feed inside the twig on the green wood working their way down.Identification
Larvae are about one to two inches long and white with a yellowish-brown head. Adults are cylindrical, with a black head, wing covers, and abdomen. The thorax is orange with three black dots. The dogwood twig borer, Obrea tripunctata, is in the order Coleoptera and family Cerambycidae.
Life History
Adult borers appear in early June. They girdle the tips of branches and deposit their eggs on the living twigs near the girdling. Eggs hatch and the larvae enter the twig and bore down the center. Damage usually causes death to branches and ruins the appearance of shrubs or trees. The larvae overwinter in the stems. In spring some of the larvae pupate while others continue to develop into the second year. The pupating larvae emerge by mid May or early June. There is one generation per year. Larvae or pupae overwinter.Control
Pruning and burning infested twigs is an effective control measure. Spraying with recommended insecticides prior to budding will also control this borer.Rights
Virginia Cooperative Extension materials are available for public use, re-print, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University.
Publisher
Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Alan L. Grant, Dean, College of Agriculture and Life Sciences; Edwin J. Jones, Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; Jewel E. Hairston, Administrator, 1890 Extension Program, Virginia State, Petersburg.
Date
May 1, 2009