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At the first sign of caterpillars on a tree, spray with Garden Insect Spray with Spinosad or Bug Buster Pyrethrin Insect Spray, and repeat the spray every two to three weeks until the feeding period has ended. In the fall, remove any visible egg nests or spray them with Horticultural Oil Insect Spray. In the spring, place a sticky TreeHelp Bug Band on the trunk of the tree to prevent the caterpillars from migrating from the ground up towards the tree’s leaves.
In the early spring, treat trees that are too tall to spray with Once-A-Year Insecticidal Drench w/Merit, to provide insect protection throughout the growing season.