Poplar Clearwing Moth (Paranthrene dollii dollii)

From: Ostry, Michael E.; Wilson, Louis F.; McNabb, Harold S., Jr.; Moore, Lincoln M. 1988. A guide to insect, disease, and animal pests of poplars. Agric. Handb. 677. Washington, DC: U.S. Department of Agriculture. 118 p.

Importance- The larvae attack the basal part of the stem of young Populus throughout the Southern United States. Stems weakened by heavy tunneling can be broken by wind. In nurseries, heavily infested stools cannot support vigorous growth from sprouts; stems often break off and die before cuttings are harvested.

Look For: Sap flow from base of stem. Stems broken over at ground. Pile of wood shavings near tree base. White to pinkish larvae with brown heads about 1 to 1½ inches long inside stem base.

Clearwing borer damage at tree base.

Biology- Adult females lay eggs in the bark crevices near the stem base. Larvae hatch and tunnel in the root collar and lower stem. Larvae overwinter in the galleries and pupate in the spring. Adults emerge in April in the first generations. Second-generation adults emerge in August.

Monitoring- Inspect nurseries and young plantings for evidence of the borer. If you find damage on 5 percent of stools in the nurseries or 20 percent of young trees in plantations, consider treatment.

Control:

• Rogue out and destroy all infested stools in the nursery.
• Plant uninfested cuttings.
• Apply an insecticide recommended for wood-boring insects.