Spruce bud scale
Physokermes piceae
26 host plants
Last updated
This profile contains verified pest data from extension databases. Regional field notes and expert review are in progress.
The reddish-brown covering of spruce bud scale resembles a spruce bud, making it often unrecognized on new shoot bases. Small scales cluster in groups of 3-8 at the base of shoots. Heavy infestations cause branches to appear black from sooty mold growth on honeydew, with lower branches becoming ragged and sometimes dying.
Immatures overwinter at bud bases; one generation per year with crawlers appearing in June. Scout needles at bud bases in winter for scale presence. Horticultural oil in early spring targets overwintering immatures. Prune infested branches if needed. Maintain tree vigor.
Quick Reference
Cultural Controls
- Natural enemies such as ladybird beetles and green lacewings help control scale populations.
- Avoid use of broad-spectrum insecticides which kill these and other beneficial insects.
- Hand-wipe to help control minor infestations.
- Prune and destroy heavily infested branches, when practical.