Ornamental Cherry: Pear slug

categories: Ornamental Cherry Ornamental Cherry Insects Ornamental trees Ornamentals

revision date: 2023-04-04 12:00

Pear slug and damaged leaf from feeding.
Pear slug and damaged leaf from feeding
Photo by: R.D. Akre

Biology

Pear slugs, or pear sawflies, are insect larvae which resemble a small greenish or black slug. They are typically 1/4″ to 1/2″ long, tadpole-shaped, and produce large amounts of slime. The adult sawfly is a small, dark, wasp-like insect which is usually about 1/4″ long. The larvae feed on the leaves of cherry, plum, and pear trees. Leaves are typically skeletonized (the upper layers of the leaf are eaten away, leaving only the veins and the lower leaf surface). Heavily damaged leaves often drop from the tree. The pear slug has two generations per season and can be found from mid- to late spring and again in late summer.

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 individual larvae.
  • Hose pear slugs from foliage with a strong stream of water.

Chemical Management

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

  • Apply when sawflies and damage are noticeable.
  • 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.