The bronze birch beetle is a destructive beetle larva that feeds on birch trees weakened from drought, poor growing conditions or other insect infestation.
To detect bronze birch beetle, look for off-colored and sparse leaves in the upper part of the birch tree, dead branches, and swollen ridges on the trunk and branches. Small, D-shaped holes in the bark are the exit points of the adult borer.
Borers make long, winding tunnels under the tree bark. This causes the truck or branch to die from lack of water and nutrients.
Management and Treatment
Application of an insecticide in early to mid-May can reduce further borer infestations. Proper planting of birch trees is also important. Birches struggle in clay soil, so it is important to select a well-drained, sandy soil.
After planting, keep the tree healthy by fertilizing, watering, mulching and controlling other insects and diseases. Fertilization can increase a birch's tolerance to borer attacks and help it overcome borer damage.