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Caption: Juniper scale
Photo by: Unknown
  
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Juniper : Juniper scale
(revision date: 2/14/2019)


Biology
The juniper scale is a small, round, white to gray scale with a yellow dot at the center. Leaves, twigs, branches, and cones may be attacked. Symptoms of scale feeding include loss of normal color and luster of foliage, no new growth, and yellowing and death of branches. Severe infestations may kill entire plants. The scales excrete large amounts of honeydew, a sweet, sticky material, which may become covered with sooty mold. Red cedars, and Irish, Savin, and Pfitzer junipers are commonly attacked.
Management Options

Non-Chemical Management
  • Ladybird beetles and parasitic wasps help control scale populations.
  • Minor infestations may be wiped off by hand.
  • Where practical, prune and destroy heavily infested branches.
  • Keeping junipers healthy can suppress the impact of this scale.
Select non-chemical management options as your first choice!

Chemical Management


Scout for crawlers. Apply to control the immature crawler stage, usually in late spring to early summer. 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
  • Bonide Systemic Insect Control
    Active ingredient: acephate  |  EPA reg no: 239-2461-4
  • 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.
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Caption: Juniper scale
Photo by: Unknown