Bronze birch borer

The bronze birch borer, Agrilus anxius, is common east of the Cascades. Damage to trees can be severe, often deadly.

The presence of the bronze birch borer in the Portland metro area had been positively confirmed as of October 23, 2003. The population looks extensive, quite established and has killed trees in the Beaverton/Tigard area. This is in addition to a positive identification in Corvallis. This flatheaded beetle borer will likely increase its distribution in Western Oregon. It may be possible to slow the movement of this borer by good site selection and choice of more resistant birches, cultural habits, and proper management of existing infestations which may include chemical intervention or tree removal. If you know landscapers in the area, please let them be alert to this.

The following websites offer more information regarding its life cycle, damage, and management.

Ohio State University Fact Sheet: Bronze Birch Borer Management This fact sheet describes management strategies and includes Degree Day information.

University of Illinois Extension Bug Review: Bronze Birch Borer. This site is nice for having both English and Spanish language versions of their fact sheet.

University of Minnesota Extension: The Bronze Birch Borer and Its Management
This has a nice chart listing the resistance of birch trees susceptibility to bronze birch borer.

Purdue Ornamentals and Turf: Bronze birch borer

USDA - Forest Service Forest Insect and Disease Leaflet - Bronze Birch Borer A nicely presented leaflet with good diagrams of classification of borer damage stages in trees.

Bronze birch borer adult
Photo: Rosetta

Bronze birch borer adult and emergence hole

Photo: Rosetta

Stained bark and emergence hole indicating bronze borer infestation

Photo: Rosetta

Bronze birch borer galleries (bark removed)

Photo: Ken Gray

Page last modified 10/24/07