Rose leaf-rolling sawfly

The Rose leaf-rolling sawfly (Blennocampa phyllocolpa), belonging to the Tenthredinidae family, is a specific pest that primarily targets rose bushes. While adult sawflies are small, wasp-like insects, the damage is caused by their larvae, which are specialized feeders.

This pest is found globally wherever roses are cultivated. It primarily affects garden and wild roses, causing leaves to curl into tight cylinders. This damage significantly impairs the plant's ability to photosynthesize, often leading to reduced vigor and unsightly foliage throughout the growing season.

The life cycle begins in spring when adults emerge from the soil. Females deposit eggs into the leaf tissue, which triggers the leaf to curl into a protective chamber for the larvae. After completing their development inside these rolls, the larvae drop to the ground to pupate in the soil until the following spring.

The primary symptom of an infestation is the characteristic curling of the leaf edges or the entire leaf into a roll. Inside, the larvae feed on the epidermis, creating brown patches and eventually causing the leaves to wither, turn yellow, and drop prematurely, which severely affects the aesthetic value of the plant.

Management and control strategies for this pest include:

• Hand-picking and disposing of rolled leaves immediately upon detection to stop larval development.
• Cultivating the soil beneath the rose bushes in late autumn to expose and destroy overwintering pupae.
• Applying appropriate systemic insecticides if the infestation levels are high and causing widespread damage.
• Encouraging natural predators, such as birds and parasitic wasps, that help maintain low population levels.