Sutherlin FFA

Flatheaded Fir Borer

Hosts: Douglas-Fir, True Fir, Western Larch, Spruce, Western Hemlock

Infestation Characteristics: It's very hard to detect attacks prior to the yellowing of the tree's crown. It is sometimes possible to identify infested green trees in the fall and winter months from the patches of bark removed from woodpeckers. The only way to confirm an attack is to remove the bark and look for its distinctive gallery pattern caused by them boring.

Flathead Fir Borers commonly attack trees that are pole sized or larger and tend to breed in trees that are felled, weakened by fire, defoliated or other types of disturbed trees.

Adult beetles have a metallic bronze or black body color and sometimes yellow spots are present and vary in size.

Control: Flathead Fir Borers commonly attack damaged Douglas fir trees with more than 50% of the crown or 25% of the cambium damaged by fire. These trees should be removed to prevent a buildup of Borer populations.