What's eating my norway spruce?

Norway Spruce (Picea abies), including the traditional Christmas tree, is attacked most by spruce aphid, which silently strips needles from autumn through spring. Spruce pineapple gall adelgids disfigure shoot tips. Spider mites are serious in hot summers. Bark beetles are the most lethal pest of stressed or drought-weakened trees.

Pale-green aphids on needle undersides from autumn onwards; needles turn yellow-grey and drop in spring — interior branches are stripped first, making trees look thin Spray with insecticidal soap or pyrethrum in late winter; knock off with a water jet on smaller trees; systemic insecticide for severe infestations; monitor from September onwards

Pineapple-shaped galls at tips of new growth; disfigures the tree and kills the growing point inside each gall; multiple galls weaken overall growth Cut out and destroy galls before late summer; horticultural oil in late winter targets nymphs at leaf base; repeat in two seasons to reduce resident population

Bronze, dry, stippled needles — most obvious on lower, inner crown; fine silk webbing under a lens; premature needle drop in midsummer Increase humidity; strong water sprays; introduce predatory mites on bonsai; apply miticide (abamectin or bifenazate) in spring before populations peak

Resin tubes at bark entry holes on the trunk; engraver galleries visible under peeled bark; crown turns red-brown then dies; rapid tree death in hot summers No cure once established — remove and destroy infested timber immediately; keep trees vigorous through watering; avoid stacking spruce logs near living trees; a significant forestry emergency pest