Spruce bud scale
Physokermes piceae
27 host plants
Last updated
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
Order
Hemiptera
Type
scale
Host Plants
27
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.
Host Plants (27)
Microbiota decussata Russian Arborvitae, Siberian Cypress Picea abies Norway Spruce Picea abies var. pendula Weeping Norway Spruce, Pendulous Norway Spruce Picea asperata Dragon Spruce Picea breweriana Brewer Spruce, Brewer's Weeping Spruce Picea engelmannii Engelmann Spruce Picea gemmata Szechwan Spruce Picea glauca White Spruce, Canadian Spruce, Skunk Spruce Picea koyamae Koyama's Spruce, Yatsugatake-tohi [Japanese] Picea mariana Black Spruce, Bog Spruce, Swamp Spruce Picea omorika Serbian Spruce Picea orientalis Caucasian Spruce, Oriental Spruce Picea pungens Colorado Spruce Picea pungens var. glauca Colorado Blue Spruce Picea rubens Red Spruce Picea sitchensis Sitka Spruce Picea wilsonii Wilson's Spruce Platycladus orientalis Chinese Arborvitae, Oriental Arborvitae Taxus baccata English Yew Taxus brevifolia Pacific Yew Taxus canadensis Canadian Yew, American Yew, Ground Hemlock Taxus cuspidata Japanese Yew Taxus media Hybrid Yew, Anglojapanese Yew Thuja occidentalis Eastern Arborvitae, American Arborvitae Eastern White-cedar Thuja orientalis Chinese Arborvitae, Oriental Arborvitae Thuja plicata Western Redcedar Thujopsis dolabrata Elkhorn Cedar, Deerhorn Cedar, Hiba Arborvitae, False Arborvitae
Data Maturity Baseline Extension data. Expert review underway.