Damage

• If your tree is infested with borers, you may notice dead or dark areas of bark, holes in the wood and insect frass resembling sawdust. Larvae chew tunnels through the inner bark layer of the tree, which may cause the tree to weaken, lose limbs, stop growing or even die. Some borers do so much damage that a single larva can kill a young tree.
  
  

Types

• Flatheaded appletree borer, roundheaded appletree borer, shothole borer, peachtree borer, lesser peachtree borer, dogwood borer, and carpenterworm are some of the boring insects that infest fruit trees in the United States.
  
  

Prevention

• Healthy trees are unlikely to be invaded by borers. Choose a site for your trees that will minimize plant stress caused by freezing, sun scalding, and wind. Take good care of your trees by watering, fertilizing, and pruning them, and remove any dead or damaged limbs.
  
  

Treatment

• In some cases, a tree can be dewormed by hand. If you can find where the larvae have tunneled in, you may be able to dig them out with a knife and remove them. Generally, chemical pesticides are needed to control borers, and sprayings must be carefully timed with the insect's life cycle in order to be effective.
  
  

Significance

• The peach tree borer is the most economically important pest of peach and plum trees.