90% confidence
Based on 20,000+ analyzed cases
Rose Slugs on rose
What's Happening
Rose slugs are the larvae of sawflies. They look like tiny green caterpillars and feed on the underside of rose leaves in spring, eating the green tissue and leaving only the transparent veins (skeletonization).
How to Fix It
- 1
Inspect the undersides of leaves at the first sign of transparent spots
- 2
Hand-pick or wipe off minor infestations
- 3
Spray undersides of leaves with insecticidal soap, neem oil, or spinosad
- 4
Note: Bt (Bacillus thuringiensis) does not work on sawfly larvae because they are not true caterpillars
How to Prevent It
Regular inspection in mid-to-late spring. Horticultural oil applied during the dormant season can help smother overwintering pupae in the soil.
Related Problems
Frequently Asked Questions
What causes rose slugs on my plant?
Rose slugs are the larvae of sawflies. They look like tiny green caterpillars and feed on the underside of rose leaves in spring, eating the green tissue and leaving only the transparent veins (skelet...
How do I fix rose slugs?
Inspect the undersides of leaves at the first sign of transparent spots. Hand-pick or wipe off minor infestations.
How do I prevent rose slugs from happening again?
Regular inspection in mid-to-late spring. Horticultural oil applied during the dormant season can help smother overwintering pupae in the soil.