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Forest & Grassland Health

Story Map of 2018 Alaska Forest Health Highlights. Spruce beetle. Story Map of 2017 Alaska Forest Health Highlights. Spruce bud blight (<em>Gemmamyces piceae. Aspen running canker. Dead yellow-cedar crop trees in a 34-year-old young-growth stand on Kupreanof Island. Hemlock sawfly defoliation in Southeast Alaska in 2018.Bird vetch.Spotted knapweed removal.

Common Forest Insects & Diseases in Alaska

Select forest diseases, insects and noninfectious disorders from the menu below for their current status, distribution, historic activity, symptoms, biology, and impacts to host trees and forest management.
Also see our Forest Health Conditions Reports and Story Maps.


Foliage Diseases

Shoot & Bud Blights

Stem Diseases

Root Diseases

  • Annosus/Heterobasidion Root & Butt Rot
  • Armillaria Root Disease

Invasive Pathogens


Forest Decline

Abiotic & Animal Damage


Bark Beetles and Woodborers

  • Ambrosia Beetle
  • Northern Spruce Engraver
  • Spruce Beetle
  • Western Balsam Bark Beetle

Defoliating Insects

Conifer Defoliators
Hardwood Defoliators – External Leaf Feeding
Hardwood Defoliators –
Internal Leaf Feeding


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