red rose stems

Asked May 23, 2019, 3:20 PM EDT

Does the appearance of the rose stems in the submitted picture suggest rose rosette virus? Also what is responsible for eating the leaves in the second picture? Initially, the skeleton of the leaf remains but the chlorophyll-bearing tissue is gone. Then a full-blown hole develops.

Baltimore County Maryland shrubs rose slugs pest insects and mites rule out rose rosette

1 Response

New growth on roses is often red. Our pathologist doesn't think this is rose rosette disease.
The holes in the leaves are being caused by a tiny worm/caterpillar-like pest referred to as a rose slug. It is not a slug or a caterpillar but the larval stage of a sawfly.
Here is more information on them:
https://extension.umd.edu/hgic/topics/rose-slugs-shrubs


Christine