Leafrollers

Leafrollers can be a headache for any orchardist or hobby fruit grower. These tortricid moths lay their eggs on various fruit, nut, and ornamental trees.

The larvae create protective tubes out of leaves, hence the name leafroller, and use webbing to hold them together. Inside the rolled leaf, they will feed and eventually pupate. This protective structure makes it hard to control them with conventional insecticides.

Leafroller Damage

Leafroller larvae are more likely to feed on new leaf growth. If infestations are particularly bad, young or newly planted trees can become entirely defoliated. The damaged leaves will appear ragged and have webbing that folds them together.

Some species of leafrollers will feed close to fruit and cause damage to young fruit. Older larvae can be seen feeding directly on fruit, either on the skin or on the flesh.

How to control Leafrollers

The first step to keeping leaf rollers off your trees is monitoring and prevention. Pheromone traps and mating disruption attractants can confuse adult males and keep them from mating.

During the growing season, look for larvae and quickly apply treatments as early as possible. Sprays are rarely necessary and should only be applied when there is clear evidence of a damaging population, such as large numbers of larvae or egg masses.

Effective sprays include:

For fruit trees, spraying should occur no later than petal fall to prevent damage to young fruit. Use high-pressure or hose-end sprayers to ensure the material reaches the protected areas where larvae are found.

Biological control is another option that can passively control leafrollers for you. Parasitic insects like tachinid flies, ichneumonid wasps, and braconid wasps can effectively reduce larval numbers. The parasitic insects will lay eggs inside the larvae and consume them from the inside out.

Natural predators like lacewing larvae, assassin bugs, predatory beetles and some birds can also reduce the population size of leafrollers.