Juniper: Juniper scale

categories: Conifers Juniper Juniper Insects Ornamentals

revision date: 2023-02-07 12:00

Green arborvitae leaves with white spots that are the scale.
Juniper scale
Photo by: Unknown

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

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • 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.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • 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.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.