leafroller

Leafroller is a common name for the larval stage of various moths in the family Tortricidae. Leafroller larvae roll or fold leaves of their host plants and secure the shelter with silk, within which they feed and develop. Adults are small moths with narrow forewings and a bell-shaped resting posture; eggs are laid on new growth or the undersides of leaves. Larvae commonly appear in spring or early summer, depending on climate.

Hosts and damage

Leafrollers attack a wide range of plants, including apples, pears, stone fruits, citrus, grapes, and ornamental shrubs. The typical injury is leaf curling or distortion as a shelter is constructed, with feeding inside the shelter possibly damaging young shoots, buds, and developing fruit. Severe infestations can reduce vigor and yield, and aesthetic damage can affect market value in fruit crops.

Life cycle

In many species, leafrollers overwinter as pupae or eggs. In spring, hatchlings or newly hatched larvae begin feeding inside rolled leaves. They grow through several instars, then pupate either inside the leaf shelter or in nearby crevices. Adults emerge to mate and repeat the cycle.

Management

Monitoring involves regular scouting for rolled leaves and signs of frass, and, where available, pheromone traps to track adult activity. Control measures typically target young larvae and may include targeted insecticides, biological options such as Bacillus thuringiensis kurstaki, and releases of parasitoid wasps. Cultural controls include pruning and removing infested shoots, cleaning up plant debris, and removing heavily damaged foliage. In some crops, dormant horticultural oils and resistant cultivars can help reduce damage. Integrated Pest Management emphasizes timely intervention and minimizing non-target effects.