What's eating my sanders blue spruce?

Sanders Blue Spruce (Picea glauca 'Sanders Blue') is a compact blue-needled white spruce most commonly attacked by spruce spider mites and Cooley spruce gall adelgids, which are the dominant pests across all Picea glauca selections. Deer occasionally browse young plants in winter. Good cultural care and spring monitoring are the first line of defense.

Stippled, yellowing-to-bronze needles with webbing; foliage loss weakens the plant and mars the ornamental blue color. Apply horticultural oil before bud break; use insecticidal soap mid-season; reduce drought stress which intensifies outbreaks.

Pineapple-shaped galls at shoot tips disfigure and kill new growth each spring. Prune and dispose of galls in late spring before they open; treat with dormant oil in early spring.

Browsed and shredded branch tips in late fall and winter; young plants can be severely damaged. Erect wire caging around young plants; apply deer repellent sprays and reapply after rain; fence the planting if pressure is heavy.