Tree borers are insects that infest trees under bark and damage them extensively by boring and tunneling through the wood. Trees that are growing poorly or are already under stress from inadequate care and disease are more prone to infestation from the insects. Take preventative action against borers by keeping trees in good health and regularly inspecting to detect early signs of damage. In case an infestation has occurred, use any of a number of recommended insecticides to kill the pests.
Use products containing chlorpyrifos, lindane or endusulfan to kill tree borers.
Spray the entire trunk and branches of the infested tree. Though the insecticides cannot reach the larvae that have already tunneled to the sapwood, they will kill all larvae and adults present on the bark surface.
Apply fumigant products to repel the borer adults that can lay eggs on the tree. The fumigants will kill any larvae that they reach. Recommended fumigants include products containing ethylene dichloride and paradichlorobenzene.
Inject chemicals like dicrotophos, oxydemeton-methyl or acephate directly into the cambial tissues of the tree where the insects commonly feed. This process is highly effective at getting rid of the pests. All chemicals are sold under different trade names.
Repeat spray applications on infested trees after three to 10 weeks. When spraying, cover all areas of the trunk and branches.