WSU Extension


Ornamental Plum
Armillaria root rot 
Brown rot 
Crown gall 
Cytospora canker 
Plum pockets 
Shothole (Coryneum blight) 
Silver leaf 
Hop aphid 
Leaf curl plum aphid 
Peachtree borer 
Pear slug 

print version| pdf version| email url    
Caption: Leaf curl plum aphids
Photo by: R.D. Akre
Ornamental Plum : Leaf curl plum aphid
(revision date: 2/14/2019)

The leaf curl plum aphid is typically pale green to yellow in color during the summer and darker green to brown later in the year. The aphids overwinter as eggs on plum and prune trees, then may migrate to various summer hosts or remain on the plum trees. Feeding by the leaf curl plum aphid causes severe curling of leaves on plum.
Management Options

Non-Chemical Management
  • Wash aphids from plants with a strong stream of water.
  • Remove aphids by hand (when practical) to control small infestations.
  • Natural predators and parasites, including ladybird beetles, lacewings, and parasitic wasps, help control aphid populations.
  • Control honeydew-feeding ants, which may protect aphid colonies.
  • Provide proper nutrition. High levels of nitrogen in the foliage encourage aphid reproduction. Switch to a slow-release or low-nitrogen fertilizer.
Select non-chemical management options as your first choice!

Chemical Management

Applications must be made early and before leaves curl. Apply oils in early spring before bud swell. 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.
  • Hi-Yield Dormant Spray
    Active ingredient: oil/pet distillate  |  EPA reg no: 7401-428
  • 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
  • Safer Brand Insect Killing Soap Conc II [Organic]
    Active ingredient: potassium laurate  |  EPA reg no: 42697-60
  • This list may not include all products registered for this use.

+ Show larger images

Caption: Leaf curl plum aphids
Photo by: R.D. Akre
Caption: Leaf curl plum aphid damage
Photo by: K. Grey
Caption: Leaf curl plum aphid adult
Photo by: K. Grey
Caption: Leaf curl plum aphid nymphs
Photo by: K. Grey