WSU Extension

Hortsense

Apple
 
Disease
Anthracnose and Bull's-eye rot 
Bitter pit 
Burrknot 
Crown and collar rot 
Crown gall 
Cytospora canker 
Fire blight 
Fruit russeting 
Nectria canker (European canker) 
Nectria twig blight (Coral spot) 
Perennial canker (Bull's-eye rot) 
Phytophthora fruit rot 
Powdery mildew 
Scab 
Virus diseases 
Insect
Aphids 
Apple ermine moth 
Apple maggot 
Apple-and-thorn skeletonizer 
Brown marmorated stink bug 
Codling moth 
Cutworms and armyworms 
Earwigs 
Fruittree leafroller 
Leafhoppers 
Leafrollers 
Lecanium scale 
San Jose scale 
Spider mites 
Tent caterpillars 
Tentiform leafminer 



print version| pdf version| email url    
Caption: Leafroller damage on apple
Photo by: A.L. Antonelli
  
Apple : Leafrollers
(revision date: 4/11/2018)


Biology
Characteristic signs of leafroller feeding include leaves that are rolled and tied in place with webbing, often with frass in the webbing. Damaged leaves are often near shoot tips and may be skeletonized or chewed. Leafrolling caterpillars on apple are usually green with light to dark brown or black heads. The caterpillars may be up to 1" in length at maturity. The adult moth of the obliquebanded leafroller, a common pest on apple, is an orange-brown, bell-shaped moth about 1/2" long. The adult of the pandemis leafroller is a buff-colored moth with tan bands on the wings. Fruittree leafrollers may also be found on apple.
Management Options

Non-Chemical Management
  • Hand-pick and destroy individual caterpillars when practical.
  • Pinch to kill caterpillars inside rolled leaves.
  • Encourage natural enemies of caterpillars including birds, parasitic wasps and flies, and predacious beetles. Avoid use of broad-spectrum insecticides which kill beneficial insects.
Select non-chemical management options as your first choice!

Chemical Management

Bacillus thuringiensis (Bt) will control leafrollers only if they are actively feeding. Use a spreader-sticker with liquid Bt formulations. Oil applied as a delayed dormant spray will kill overwintering eggs. Apply spinosad once around the time of petal fall. 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.

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.
  • All Seasons Horticultural & Dormant Spray Oil Conc [Organic]
    Active ingredient: oil/pet distillate  |  EPA reg no: 4-80
  • Azamax Botanical Insecticide, Miticide, & Nematicide [Organic]
    Active ingredient: azadirachtin  |  EPA reg no: 71908-1-81268
  • Bonide Captain Jack's Deadbug Brew R-T-U [Organic]
    Active ingredient: spinosad (spinosyn A+D)  |  EPA reg no: 4-472
  • Bonide Thuricide BT Conc
    Active ingredient: Bacillus thuringiensis subsp. kurstaki  |  EPA reg no: 4-226
  • Bull's-Eye Bioinsecticide
    Active ingredient: spinosad (spinosyn A+D)  |  EPA reg no: 62719-314-56872
  • Monterey Garden Insect Spray [Organic]
    Active ingredient: spinosad (spinosyn A+D)  |  EPA reg no: 62719-314-54705
  • Naturalis L
    Active ingredient: Beauveria bassiana  |  EPA reg no: 53871-9
  • Ortho Volck Oil Spray Dormant Season Insect Killer Conc
    Active ingredient: oil/pet distillate  |  EPA reg no: 239-16
  • R-T-U Year-Round Spray Oil
    Active ingredient: oil/pet distillate  |  EPA reg no: 6218-78
  • Safer Brand BioNEEM Multi-Purpose Insecticide & Repellent Conc [Organic]
    Active ingredient: azadirachtin  |  EPA reg no: 70051-6-42697
  • This list may not include all products registered for this use.
Images

+ Show larger images

 
Caption: Leafroller damage on apple
Photo by: A.L. Antonelli
Caption: European leafroller
Photo by: S.M. Fitzpatrick and J.T. Troubridge
Caption: Obliquebanded leafroller adult
Photo by: J.F. Brunner