Holly: Orange tortrix
categories: Holly Holly Insects Ornamentals Shrubs
revision date: 2023-04-12 12:00
Photo by: R. LaLone
Biology
The larval stage of the orange tortrix is a leafrolling caterpillar. The larvae are tan to pale green with tan heads and about 1/2″ long at maturity. The feeding caterpillars typically roll or twist individual leaves or clusters of leaves at shoot tips and tie them into loose nests with webbing. The larvae are very active when disturbed. The orange tortrix is a pest of many woody plants, including fruit trees and several common landscape plants such as holly, rose, euonymus, oak, and willow.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Hand-pick and destroy rolled leaves, or pinch to kill caterpillars inside.
- Prune out webbing, if desired.
- Provide proper culture. Healthy plants can easily tolerate some defoliation.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
- Apply when caterpillars or damage is first noticed.
- Sevin (carbaryl) is particularly dangerous to honeybees since it does not immediately kill them. They return to the hive with the poison and distribute it within. Therefore avoid carbaryl if at all possible if there is a chance of pesticide drifting onto nearby blooming plants.
- Bacillus thuringiensis (Bt) will control leafrollers only if they are actively feeding.
- Use a spreader-sticker with liquid Bt formulations.
- Homeowners should not make foliar applications to trees over 10 ft tall.
- Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.
Approved Pesticides
Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.