Bronze Birch Borer

Insect Pest

Moderate Threat

Affects: European white birch (highly susceptible), paper birch, other birch species

Photo: E. Bradford Walker / Vermont Department of Forests, Parks and Recreation (CC-BY-3.0-US (Bugwood))

Identification & Biology

Native beetle that attacks stressed birch trees. Larvae bore under bark, killing branches from top down. European white birch (the popular ornamental) is far more susceptible than native species.

Current Status

Established throughout PNW urban areas.

States affected:

Oregon Washington

What Homeowners Should Do

Keep birch well-watered - drought stress is the #1 trigger. Mulch root zone. Consider replacing European white birch with resistant River Birch or native paper birch.