Chemical Control Chemical control is preventive when insecticide is applied to trees before borer eggs hatch, so that small borer larvae contact a toxic residue as they crawl into trees. Control may also be achieved by fumigant action of the insecticide, which can kill larvae already in trees at the time of application. An insecticide with long residual action gives the best control of peachtree borer. Protection from peachtree borer is most critical during the first three to five years after planting. In established plantings, insecticide should be applied as a bark drench at a rate of one-half to one gallon of spray mix per tree.
Thorough coverage is necessary.
The insecticide should run down the trunk and soak the ground at the base of the tree. Any prunings, debris, or weeds at the base of trees should be removed so that they do not block the treatment. Timing The best time to treat and the number of insecticide applications needed for peachtree borer control depend on whether trees are known to be infested with this pest. If trees are infested by both peachtree borer and lesser peachtree borer, then insecticide application should be delayed until early September. Insecticide should be applied to the bark by a paint brush or a hand sprayer.