Non Pesticide Borer Control in Fruit Trees

 Q. I did not want to use a pesticide to control borers in my fruit trees. Any other options you can think of?

I have had some luck controlling borers in fruit trees using a knife. They are inspected frequently during "borer season".

A. I understand your concerns about using pesticides in fruit trees. In the desert it is more difficult when borer numbers in older neighborhoods are a problem. These beetles can be in pyracantha, cotoneasters, flowering plum, and other trees and shrubs in the rose family.

Control Sun Damage

Borer damage can be minimized by controlling sun damage to fruit trees, lowering the numbers of borers in a community and cutting out damage when it is seen using a clean knife. First is sun damage. Protect exposed parts of a susceptible fruit trees with shade. Shade the trunk and exposed limbs with either water diluted paint, its own growth, or anything to decrease the sun damage.

Next is a high population of borers can lead to lots of borer damage. Borers are the “worms” or larvae of the adults which are beetles. Some communities, particularly older ones, have no control of borer infested trees and shrubs. This leads to an extremely high population of borers that fly about looking for places to lay eggs in these communities. 

Borer control with a knife

When they become adults, borers exit the tree as the adult beetle. The adult beetle flies, mates, and the female lays eggs again, usually on sunburned wood of susceptible trees. No one knows exactly when these borers fly but they can be anytime from March until warm weather stops in the fall.

Borer control using a sharp knife on small branches

Watch for borer damage to occur. If you are paying attention, damage can be seen in early March, but its outward appearance isn’t visible to most until July and August. Then the leaves turn brown and hang from one or two dead branches. If the damage is seen early enough, dig out the living “worms” just under the bark of fruit trees using a sharp, clean knife.