WSU Extension

Hortsense

Pear
 
Disease
Crown gall 
European canker (Nectria canker) 
Fire blight 
Pacific Coast pear rust 
Pear trellis rust 
Powdery mildew 
Pseudomonas blossom blast and dieback 
Scab 
Stony pit 
Virus diseases 
Insect
Aphids 
Apple-and-thorn skeletonizer 
Brown marmorated stink bug 
Codling moth 
Cutworms and armyworms 
Pear psylla 
Pear slug (pear sawfly) 
Pearleaf blister mite 
San Jose scale 
Spider mites 



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Caption: Spotted cutworm
Photo by: K. Grey
  
Pear : Cutworms and armyworms
(revision date: 7/10/2015)


Biology
Cutworms and armyworms are the larvae of noctuid moths. These common moths are typically medium-sized with fairly dull coloration. The gray to tan caterpillars are hairless, nocturnal, and generally spotted, striped, or otherwise marked. They may be 1/4" to 1" in length and tend to curl up when disturbed. Cutworms and armyworms feed by chewing leaves and buds, typically on lower portions of the tree. Symptoms of damage include ragged, irregularly chewed leaf margins and buds damaged prior to bloom. Fruit may also be damaged, with small to large holes chewed into the surface. While armyworms typically feed during the day, cutworms usually feed at night. It is advisable to search for them with a flashlight in the dark, as cutworms typically spend the day just beneath the soil surface or under debris near the host. Weeds are the primary hosts of cutworms.
Management Options

Non-Chemical Management
  • Use a sticky material such as Tanglefoot or Stik-Em. It is applied to a polyethylene strip secured around the trunk and acts as a barrier to prevent access to the foliage. Keep in mind that low-hanging branches and tall weeds may also provide access.
  • Hand-pick night-feeding larvae, when practical.
  • Cut weeds and remove debris from around trees.
  • Encourage natural enemies of cutworms including birds and spiders.
Select non-chemical management options as your first choice!

Chemical Management

Bacillus thuringiensis (Bt) will provide some control if caterpillars eat enough of it. 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.

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.
  • 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
  • Bug Buster-O [Organic]
    Active ingredient: pyrethrins  |  EPA reg no: 1021-1771-54705
  • Naturalis L
    Active ingredient: Beauveria bassiana  |  EPA reg no: 53871-9
  • 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

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Caption: Spotted cutworm
Photo by: K. Grey
Caption: Bertha armyworm
Photo by: K. Grey
Caption: Cutworm eggs
Photo by: A.L. Antonelli
Caption: Adult moth of the spotted cutworm, Xestia c-nigrum
Photo by: M. Bush