WSU Extension

Hortsense

Ornamental Cherry
 
Disease
Armillaria root rot 
Bacterial canker 
Brown rot 
Coryneum blight (Shothole) 
Leaf spot 
Virus diseases 
Insect
Aphids 
Apple-and-thorn skeletonizer 
Cherry bark tortrix 
Pear slug 
Redhumped caterpillar 
Scales 
Shothole borer 
Spider mites 
Tent caterpillars 



print version| pdf version| email url    
Caption: Coryneum blight symptoms on leaves and fruit
Photo by: R.S. Byther
  
Ornamental Cherry : Coryneum blight (Shothole)
(revision date: 6/26/2015)


Biology
Shothole is a fungal disease typically attacking the leaves of ornamental (flowering) cherries. Lesions are initially dark brown, reddish, or purplish spots and may be surrounded by a light green to yellowish halo. They are oval to round and expand into brown spots with light centers. The lesions are typically up to 1/4" in diameter. The centers of infected spots often die and drop out in warm weather, giving leaves the characteristic "shothole" appearance of the disease. Occasionally, twig cankers may be observed. The fungus probably overwinters on the bark and in infected buds. Spores are primarily spread by water. Coryneum can also attack stone fruits including peach, apricot, and fruiting cherries.
Management Options


Non-Chemical Management
  • Prune and destroy dead buds and cankered twigs if present.
  • Rake and destroy infected leaves.
  • Avoid overhead watering, as leaves must be moist for infection to occur.
Select non-chemical management options as your first choice!

Chemical Management

Apply at leaf fall in late autumn. Apply again at shuck fall in the spring (when flower petals have fallen away). 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.
  • Bonide Fung-onil Multi-Purpose Fungicide Conc
    Active ingredient: chlorothalonil  |  EPA reg no: 60063-9-4
  • Bonide Liquid Copper Fungicide Conc/Organic Gardening
    Active ingredient: copper octanoate  |  EPA reg no: 67702-2-4
  • Ortho Max Garden Disease Control Conc
    Active ingredient: chlorothalonil  |  EPA reg no: 239-2522
  • Spectracide IMMUNOX Multi-Purpose Fungicide Spray Conc
    Active ingredient: myclobutanil  |  EPA reg no: 9688-123-8845
  • This list may not include all products registered for this use.
Images

+ Show larger images

 
Caption: Coryneum blight symptoms on leaves and fruit
Photo by: R.S. Byther
Caption: Coryneum blight symptoms on fruit
Photo by: R.S. Byther