Brown Spruce Longhorned Beetle—Tetropium fuscum
The brown spruce longhorned beetle (Tetropium fuscum) is an invasive pest from Europe that is currently found in Nova Scotia, Canada. This pest can be moved via firewood, logs, or other raw wood products and will infest spruce, fir, pine, and larch.
Symptoms of infestation include, excessive amounts of white resin running down the trunk of the tree and abnormal foliage color (progressing through yellow, red, then gray). Signs include meandering frass-filled larval tunnels beneath the bark, “L-shaped” pupation galleries in the sapwood and oval exit holes in the bark. There are native Tetropium species that are very similar in appearance to brown spruce longhorned beetle; they do not successfully attack healthy trees.
In Maine, please report sightings of this pest or its damage to the Maine Forest Service.
Adult brown spruce longhorned beetle.
Resin flow produced by brown spruce longhorned beetle.
Larval tunnels produced by brown spruce longhorned beetle.
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Identification and Control Information
- Brown Spruce Longhorned Beetle—Maine Forest Service
- Brown Spruce Longhorned Beetle—Minnesota Department of Agriculture
- Brown Spruce Longhorned Beetle—Natural Resources Canada
More Information
- Maine Forest Service: Conditions Reports (updated regularly) including annual summary reports
[Photos, left to right: Georgette Smith, Canadian Forest Service, Bugwood.org; Jon Sweeney, Natural Resources Canada, Bugwood.org; Georgette Smith, Canadian Forest Service, Bugwood.org]