Issue: July 8, 1996

Boxelder bugs

Question: We are having difficulty eradicating box elder bugs. Do you have any suggestions. Would getting rid of the tree solve the situation?

Answer: The boxelder bugs and their close relatives, the red- shouldered bugs, are true bugs in the order Hemiptera. They are black bugs with red or orange markings on their shoulders and along the edges and ends of their wings. They feed on the boxelder and golden rain tree seeds causing little damage to the trees. They are numerous and have a bad habit of invading homes, making a nuisance of themselves. This is the reason most people seek to control them.

Removing the tree can help solve the problem if there are no other host trees nearby. If there are other boxelder or golden rain trees in neighboring landscapes, you will continue to have the bugs, but they should be fewer in number. If yours is the only host tree in the neighborhood, your neighbors might appreciate anything you do to eliminate the bugs.

There are several pesticides which may be used. Insecticides containing chlorpyrifos (TM) are often used for this purpose, but there are others also labeled for control of boxelder bugs and their relatives. These insecticides are much more effective at eliminating very young bugs; the older bugs often hide inside the seed clusters of boxelder or in the "Chinese lanterns" around the seeds of the golden rain tree. In these hiding places, they are exposed to less insecticide and as larger insects, they are less sensitive to the insecticides.

Pruning dead branches in summer

Question: There are a lot of dead branches in my trees. Is it ok to prune them out now or do I have to wait until winter?

Answer: It is wise to prune dead and dying branches from a tree right away whenever you discover them. They are easiest to identify in the summer, so go ahead and prune them. Limit pruning of healthy branches during the growing season to those which must be removed for safety reasons and try to prune them as little as possible.

The very dry nature of last winter is largely responsible for dieback in many of our trees. It is important to remove old dead branches as soon as possible as borers and diseases can get their start in trees by entering through these branches left on the tree. Since these branches are not contributing food to the tree through photosynthesis, it does no harm to remove them.