Rose Leaf-Rolling Sawfly
Rose Leaf-Rolling Sawfly, Rose Leaf Rolling Sawfly , Rose Sawfly
by Jan Sørensen. CC BY 4.0
The Rose Leaf-Rolling Sawfly is an insect that's closely related to the wasps, bees and ants. Females secrete a toxic chemical while laying eggs in the leaf tissue. This behaviour results in the leaves curling in at both margins. When hatched, the larvae begin to feast while enclosed and protected in the curled leaf!
May weaken the stems of rose plants.
Most plants recover from infestations.
Adults: The adults look like small black flies, but they're seldom seen by gardeners. Larvae: The larvae look like small, pale green caterpillars. They may be seen inside the leaf rolls. Eggs: Typically laid inside the plant by the female sawfly. The female cuts the leaf and lays eggs inside, which are difficult to see with the naked eye.
Leaf margins begin to curl downwards. The leaves roll into tubes. Small, pale green larvae may be evident within leaf rolls. The leaves will be stripped over a couple weeks.
The UK and Europe
It's been advised that lighter infestations are tolerable. If you have a light infestation with only a few leaf rolls, then these can be picked off and destroyed. For heavy infestations where most leaves are rolled; these should not be picked off. By doing so, you may damage the plant more than the sawflies themselves. Cultivating the soil that surrounds the infested plant may expose any overwintering larvae, and these can be thrown on an elevated surface and fed to the birds! Attract natural garden predators into the garden by providing spots of cover. Wild patches and strips of native wildflower/ grass can provide cover for predatory insects. Climbing plants such as ivy is excellent habitat for small songbirds. Likewise, bird tables and ponds are an excellent resource for attracting wildlife.
Unfortunately, there are currently no chemical treatments available for home gardeners that will give effective control over this pest.