Cherry: Apple-and-thorn skeletonizer

categories: Cherry Cherry Insects Tree Fruits

revision date: 2022-12-05 12:00

Apple-and-thorn skeletonizer caterpillar feeding on leaf with brown damage area.
Apple-and-thorn skeletonizer caterpillar feeding on leaf
Photo by: A.L. Antonelli

Biology

The adult of the apple-and-thorn skeletonizer is a small dark-brown or reddish-brown moth. The skeletonizer overwinters as a pupa or an adult, with the females laying eggs in the spring. The caterpillars are yellow-green in color, have black spots and brown heads, and feed on the leaves of several plants including apple, crabapple, pear, and hawthorn. Caterpillars are about 1⁄2″ long at maturity. Characteristic damage includes skeletonized leaves, or leaves that are rolled into a cone and tied with webbing. Damaged leaves are brown and papery and drop prematurely.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Hand-pick and destroy caterpillars when practical.
  • Pinch caterpillars inside rolled leaves or prune and destroy heavily infested twigs.
  • Naturally occurring enemies help control populations of apple-and-thorn skeletonizers. Avoid use of broad-spectrum insecticides which kill beneficial insects.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • Bacillus thuringiensis (Bt) will provide control to young feeding caterpillars.
  • Use a spreader-sticker with liquid Bt formulations.
  • Homeowners should not make foliar applications to trees over 10 ft tall.
  • Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.