Spruce: Spruce bud scale

categories: Conifers Ornamentals Spruce Spruce Insects

last review date: 2025-07-31 02:06

Biology

Spruce bud scales are reddish to brown in color and occur at the base of new shoots. They tend to be very inconspicuous, as they may be partly hidden by the bark.

Lower branches are often heavily infested and may be killed, while upper branches are much less affected.

Spruce bud scales produce large amounts of honeydew which is often covered with black sooty mold.

Management Options

See "Using Integrated Pest Management (IPM) in the Landscape" for successful problem management techniques.

Non-chemical Management

Select non-chemical management options as your first choice!

• Hand removal may help control spruce bud scales on small trees.
• Do not prune branches unless they are dead.

Chemical Management

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

• Apply in early summer when crawlers are present.
• Oil applications should be made during the delayed dormant period (usually some time in February).
• Horticultural oils, soap-based products and some other products may cause discoloration of spruce needles, particularly on Colorado blue spruce.
• DO NOT APPLY Safer Brand Insect Killing Soap Concentrate II to Colorado blue spruce.
• Read labels carefully and test on a small area before application.
• 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

Examples of pesticides that are legal for home use in Washington State are listed below.
The list may not include all products registered for this use.

• Safer Brand Insect Killing Soap Concentrate II [Organic]
  Active ingredient: potassium salts of fatty acid (EPA reg. 42697-60)
• R-T-U Year-Round Spray Oil
  Active ingredient: mineral oil (EPA reg. 6218-78)