Dogwood: Lecanium scale
categories: Dogwood Dogwood Insects Ornamental trees Ornamentals
revision date: 2023-04-04 12:00
Biology
Lecanium scales are rounded brown (or mottled) insects. Adults are from 1/8″ to 1/4″ in diameter. Lecanium scales produce large amounts of sticky honeydew, which may have sooty mold growing on it. They overwinter on the bark, but the crawlers feed on the underside of leaves from May to August (approximately). Scales may be spread from infested plants by people, other insects, wind, and birds.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Natural predators such as ladybird beetles and green lacewings may greatly reduce the number of crawlers.
- If the infestation is minor, scales may be wiped from the bark or leaves.
- Prune and destroy heavily infested branches.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
- Scout for crawlers.
- Insecticide applications can be effective when applied to control the immature crawlers stage, usually in late spring to early summer.
- Oils are effective in the delayed dormant period.
- Use superior type oil sprays only on overwintering nymphs.
- 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.