Leaf rollers are pests that affect gardens and fruit trees. They are caterpillars that feed on leaves, causing damage to the plant. The larvae will roll and tie the leaves together with silk to form a protected area to feed and grow.
Symptoms
- Leaves are tightly rolled, folded or twisted, making them difficult to open
- Silken webs or tunnels can be seen inside rolled leaves or along branches
- Holes or tattered edges on leaves from feeding caterpillar damage
- Frass (insect excrement) can be found on leaves or near infested areas
- Stunted or distorted growth of shoots, leaves, or fruit
- Yellowing or browning of leaves or sections of the plant
- Premature defoliation or death of leaves or branches.
What is a Leaf Roller
- A plump, segmented caterpillar, often with a green or brown body
- A well-defined head with two antennae
- Tiny legs on each segment of the body
- A length of up to 1.5 cm when fully grown
- Some species may have distinctive markings or patterns on their bodies
- Can be easily distinguished from other caterpillar pests by their habit of rolling or folding leaves for protection.
Treating a Leaf Roller Infestation
It may be necessary to use a combination of methods to effectively manage a leaf roller infestation. For example, hand picking and destroying caterpillars and rolled leaves, combined with the use of horticultural oils or insecticidal soaps, can provide quick relief.
Physical removal
- Handpick caterpillars and rolled leaves from the plant and destroy them.
- Cut off infested sections of the plant and dispose of them.
- Regular inspections can help to identify and remove infestations early on.
Natural predators
- Encourage natural predators such as birds, parasitic wasps, and ladybugs to visit the garden.
- Provide nesting sites and food sources to attract and retain predators.
- Avoid the use of broad-spectrum insecticides that can harm natural predators.
Horticultural oils and insecticidal soaps
- Oils and soaps work by smothering the pests and disrupting their ability to breathe.
- Apply when caterpillars are young and actively feeding for maximum efficacy.
- Follow label instructions carefully to avoid damaging the plants.
- Repeat applications may be necessary for heavy infestations.
Chemical insecticides
- Chemical insecticides can be effective against leaf rollers.
- Choose a product specifically labeled for use against leaf rollers.
- Follow label instructions carefully, including precautions for application and safety.
- Repeat applications may be necessary for heavy infestations.
- Rotate insecticides to avoid resistance development.
Cultural control
- Keep the garden clean and free of debris to reduce habitat for leaf rollers.
- Properly prune and dispose of infested plant material.
- Rotate crops to reduce populations and avoid continuous exposure to the same plants.
- Choose disease-resistant plant varieties when possible.