Borer
29 host plants
Last updated
Data Coverage 1 of 6 dimensions
You will notice round or D-shaped emergence holes in bark of poplar, willow, oak, and other hosts, with sawdust or frass accumulating at tree base. Beneath bark, larvae create winding galleries; you may find exit holes with bark flaking away. Look for branch dieback and canopy thinning on weakened trees.
Maintain tree vigor through proper watering during drought; borers colonize stressed trees. Avoid wounding trees through careless pruning. Prune and remove heavily infested branches if galleries girdle trunk. Preventive trunk sprays of permethrin in late May protect specimen trees from newly emerged adults. Once larvae tunnel inside wood, no spray provides effective control.
Quick Reference
Host Plants
29
Cultural Controls
- biological control Birds peck the larvae from under the bark with their beaks.
- Some wasp parasites attack the borer.
- Carpenter ants eat both larvae and pupae from the wood.
- Harvest mites attack pupae inside the pupal chambers.
- Management-cultural control Beetles are attracted to weakened, sunburned, or injured parts of the trunk and lay eggs in cracks on bark exposed to the sun.
- Protect young and newly planted trees from sunburn by whitewashing or painting with white interior latex paint....
Host Plants (29)
Populus alba White Poplar European White Poplar, Silver Poplar Populus angustifolia Narrowleaf Cottonwood, Mountain Cottonwood Populus balsamifera Balsam Poplar Populus canescens Gray Poplar Populus deltoides Eastern Cottonwood Populus fremontii Fremont Cottonwood, Western Cottonwood Populus grandidentata Bigtooth Aspen Populus nigra Black Poplar Populus tremula European Aspen European Trembling Aspen European Quaking Aspen Populus tremuloides Quaking Aspen Populus trichocarpa Black Cottonwood Quercus phellos Willow, Oak Salix alba Salix alba Salix babylonica Weeping Willow Salix caprea Salix caprea Salix integra Salix integra Salix magnifica Magnolia-leaf Willow, Magnificent Willow Salix matsudana Salix matsudana Salix pentandra Laurel, Willow, Bay Willow Salix phlebophylla Skeletonleaf Willow Salix purpurea Purpleosier Alaska Blue Willow Salix scouleriana Scouler's Willow Sambucus canadensis American Elderberry Sambucus nigra Common Elderberry, European Elderberry, Black Elderberry, Elderflower Sambucus nigra subsp. cerulea Blue Elderberry, Blueberry, Elder Sambucus racemosa Red Elderberry Thuja occidentalis Eastern Arborvitae, American Arborvitae Eastern White-cedar Thuja orientalis Chinese Arborvitae, Oriental Arborvitae Thuja plicata Western Redcedar