Spruce: Spruce bud scale
Photo by: A.L. Antonelli
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: Always read and follow label directions when working with pesticides.
For more information on using pesticides visit :
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Apply in early summer when crawlers are present.
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Oil applications should be made during the delayed dormant period (usually some time in February).
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Horticultural oils, soap-based products and some other products may cause discoloration of spruce needles, particularly on Colorado blue spruce.
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DO NOT APPLY Safer Brand Insect Killing Soap Concentrate II to Colorado blue spruce.
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Read labels carefully and test on a small area before application.
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Homeowners should not make foliar applications to trees over 10 ft tall.
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Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.
Approved Pesticides
If you choose to use a pesticide, some examples of products that are legal in Washington are listed below. Some products are labeled for just INDOOR or just OUTDOOR use, or may allow both uses. Be sure to choose a product appropriate for your situation. Always read and follow all label directions.
WSU Extension programs and employment are available to all without discrimination.
Evidence of noncompliance may be reported through your local Extension office.