There are many different types of insects that fall into the boring insect category, including the Asian Long-horn Beetle, Elm Bark Beetle, Birch borer, to mention just a few. The damage can be caused by the insect itself as it tunnels in the tree, as well as the larvae which also tunnel within the phloem and cambium layers, after emerging from their eggs. The borers’ tunneling weakens and kills trees by interrupting the flow of sap.
Evidence of borer infestation is a progressive thinning of the crown of the tree beginning at the top as well as distinct holes and slight sawdust on the tree’s trunk. Trees generally die after about two or three years, that is, after two or three infestations by the larvae.
Recommended Control Steps
If caught early enough, immediately apply the Multi-Insect Killer Tree Injection Kit treatment to the tree. This insecticide is injected directly into the tree’s vascular system and is released quickly to help control insects already inside the vascular system.
To prevent repeated borer attacks and in areas of known birch borer activity, a number of steps can be taken to prevent attacks in healthy trees. In the early spring, treating the tree with the Once-A-Year Insecticidal Drench w/Merit helps protect the tree’s vascular system. This treatment can be supplemented by regularly spraying (every three to three weeks) the tree’s trunk with a good dosage of Eight Insect Control, thus creating a barrier to reduce further insect penetration through the bark.
The good news is that healthy, well-situated, well-maintained, and healthy trees are normally more resistant to the borer, as well as less of a target. Trees under stress are more likely to be borer targets, so it is important to ensure that birch trees receive adequate water. To help ensure that a tree is healthy, apply a TreeHelp Annual Care Kit in the spring or early summer which contains the appropriate fertilizer.