The BWA have few predators in western North Carolina and will continue to increase in your trees unless treated chemically. Do not treat for the BWA unless it is found in your trees. Through scouting, you will know when BWA first comes into your trees. Preventative treatments do not work because coverage is not adequate. Treating unnecessarily wastes time and money, and may create problems with other insect pests.
Good control requires complete coverage of the tree.
Thorough coverage is more important than what insecticide is used. Good coverage is easiest with a high-pressure and apply at least 200 gallons per acre. Depending on the size of the trees and their density, as much as 400 gallons per acre may be necessary. Spray trees from at least two directions. Practice spraying trees with water, checking immediately to see if the entire tree is wet.