University of Maryland Extension

Roseslug Sawflies - Shrubs

Back to Insects/Mites-Shrubs

Slug on leaf
Immature roseslug on leaf
 

Key Points

  • The roseslug sawfly is one of three common sawflies that attack roses (others are curled and bristly roseslugs).
  • Adults of all three species resemble wasps and are about 1/4" long.
  • Mature larvae look like caterpillars, but they are not. They are about 1/2" long and yellow-green with yellow heads.
  • The larvae skeletonize the leaves and in heavy infestations can cause leaves to turn brown and curl.
  • Check roses in May and June (in Maryland) for the slug-like, greenish-yellow larvae on the under surface of skeletonized leaves.
  • However, roseslugs can be active through the fall.
  • If the infestation is light, pick off and destroy the larvae.
  • To control heavy infestations, use horticultural oil or spray with spinosad. Target the undersides of the leaves.
  • Control is the same for all three species.


Bristly roseslug larvae are about 5/8" long and greenish white with long, stout bristles. They skeletonize leaves by feeding from the undersides of the leaves and later chew holes through the leaves.

Curled roseslug larvae are metallic green above, marked with white dots, grayish white underneath, with yellow-brown heads. They curl up like a cutworm and are about 3/4" when mature. Curled roseslugs initially feed by skeletonizing the leaves, but eventually defoliate entire leaflets except for the largest veins.

Bristly rose slug larvae are about 5/8" long and greenish white with long, stout bristlesBristly rose slug and feeding damage

Bristly roseslug larvae are about 5/8" long and greenish white with long, stout bristles (left) - They skeletonize leaves by feeding from the undersides of the leaves and later chew holes through the leaves (right)

Coiled rose slugRose slug damage on bud
Coiled roseslug                                                  Roseslug damage on bud 

rose slug damage
Defoliated rose

Rev. 2020

Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2021. Web Accessibility

University programs, activities, and facilities are available to all without regard to race, color, sex, gender identity or expression, sexual orientation, marital status, age, national origin, political affiliation, physical or mental disability, religion, protected veteran status, genetic information, personal appearance, or any other legally protected class. If you need a reasonable accommodation to participate in any event or activity, please contact your local University of Maryland Extension Office.