Ornamental Plum: Pear slug

categories: Ornamental Plum 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


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 on their bodies. The adult sawfly is a small, dark, wasp-like insect which is usually about 1/4″ long. The larvae feed on the leaves of plum, cherry, 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 may drop. The pear slug can be found from mid- to late spring and again in late summer. There are two generations per year.

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.

  • Chemical control measures are rarely necessary except for very severe infestations.
  • Apply when larval damage approaches 25% to 30% defoliation.
  • 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.