Bronze Birch Borer

The birch tree is a very popular choice for Minnesota landscapes. They are highly attractive because of their different coloring and bark texture, as well as the characteristics of the foliage. Unfortunately, they become very stressed in urban environments due to being easily stressed and susceptible to the bronze birch borer.

The bronze birch borer is copper in color, slender, and also metallic in appearance. It measures around 3/8 of an inch in length and is not usually seen. The white larvae reside under the bark. While all species of birch trees are susceptible, certain species become victim to this insect more easily than others. The Silver Birch, European White Birch, Young’s Weeping Birch, and Himalayan Birch are just some of the types that are the most sensitive victims.


One of the first symptoms is the yellowing of leaves in the upper crown in the middle of summer. The leaves then turn brown as they die. Smaller branches in the upper crown also begin to die. Over time, the entire tree may die. While brown leaves are not always a sign of the bronze birch borer, ridges forming on the bark of the trunk is because of the larvae feeding underneath. You will also notice D-shaped exit holes on the larger branches and trunk due to the larvae reaching adulthood and exiting the tree. The emergence of borers occurs between late May and early June into July. Mating of the insects take place shortly after as the adults feed on the leaves of the tree.


The moment you notice something wrong with your tree, our professional tree service can evaluate the tree to determine the real problem behind it and implement the right treatment. It is important to catch the bronze birch borer as soon as possible so that damage is minimal and the tree can thrive. Pruning at the proper time, fertilizing when nutrients are absent, sufficient watering done over 2 to 3 hours once per week, and proper mulching 2-4 inches deep are all ways to maintain tree health. When borers are present, chemical control may be necessary to kill borers. This is done through insecticide injections into the tree.

Contact A Qualified Tree Service

If you have birch trees that are being overrun by the bronze birch borer, you are not sure, or you simply want to take preventative measures, we can help you. We treat your trees like we would treat our own. To find out more about what we can do for you, call us at 1-800-311-3919 to schedule your free quote.