How to Manage Pests

Pests in Gardens and Landscapes

Sawflies

Sawflies are named for the adult female's sawlike abdominal appendage used for inserting eggs in foliage. Adults have two pairs of wings and are dark, wasplike, somewhat flattened insects, usually 0.5 inch long or shorter. Some species mine leaves or stems. Most exposed-feeding larvae have six or more prolegs on the abdomen and one large "eye" on each side of the head. Sawflies include species that feed openly on foliage and those that mine inside stems and leaves.

Identification of speciesLife cycle

Damage

Most conifer sawflies chew needles or buds; a few mine in shoots and cause tip dieback. Broadleaf-feeding species may skeletonize or chew holes in leaves or mine tissue, causing winding, discolored tunnels. Different species roll leaves, web foliage, or cause plant galls. Some may feed in stems, causing wilting. Sawflies in forests in the western states can retard plant growth and occasionally kill trees in landscapes if populations are high.

Solutions

Trees and shrubs tolerate moderate defoliation. Prune damaged foliage and stems. Parasitic wasps, predaceous beetles, or fungal and viral diseases commonly kill sawfly populations. Avoid broad-spectrum insecticides because of their adverse effect on natural enemies. Insecticidal soap or narrow-range oil kill exposed-feeding sawfly larvae but may damage blossoms. Pear sawfly larvae can sometimes be washed off plants with a forceful stream of water.

Pear sawfly larva
Pear sawfly larva

Skeletonized leaves caused by bristly roseslug
Skeletonized leaves caused by bristly roseslug


Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2014 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/GARDEN/PLANTS/INVERT/sawflies.html revised: April 25, 2014. Contact webmaster.