Key Features
- Round Holes in Bark
- Wood Shavings
- Bark Falls Off In Sheets
Symptoms
Rapid death and decline of tree. Bark comes off of trunk in sheets, revealing white excelsior-like shavings of bark beneath.
Biology
Adult beetles and related species are attracted to coniferous trees (pines, spruce etc.) that are stressed from lack of moisture or attack by other beetles. Adults fly in the spring and chew a hole on which they lay eggs. Eggs hatch into white, worm-like larvae that shave the wood inside the tree as they tunnel underneath the trunk. As larvae get older they chew into the heartwood of the tree. In many parts of the midwest, the pine sawyer beetles can spread pine wilt disease by spreading a worm-like organism called a nematode. If you pick up a live beetle you can hear it squeak.
Management Recommendations
Once the sawyer beetles have attacked your trees it is very unlikely that they can be saved. It is best to cut and destroy trees (burn, chip or bury as local permits allow) to prevent the spread of beetles from unhealthy to healthy plants. Apply one of the residual insecticides to the remaining healthy trees to kill beetles as they bore into trees.
Effective Pesticides
Active Ingredients include: Bifenthrin, Carbaryl, Permethrin
