Identifying and Controlling Tortrix Moth on Roses

Curled leaves with cocoon-like structures and tiny black specks on a Sitka rose indicate Tortrix moth (also called leaf-roller) infestation. The larvae hatch from eggs laid on leaf undersides, then roll the leaf into a protective tube where they feed. The black dots are frass (insect excrement).

Control Methods

1. Mechanical removal: Pick off and destroy all rolled leaves. This is highly effective for light infestations and avoids chemicals.
2. Insecticidal spray: Any rose-labeled insecticide (e.g., spinosad, pyrethrin, or neem oil) applied when larvae are active will penetrate the rolled leaves. Systemic options like acephate (Orthene) also work.

Monitor regularly in spring and early summer. Removing affected leaves promptly breaks the life cycle and prevents a second generation.