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At the first sign of leafworms on a tree, spray it 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. In the spring, place a sticky TreeHelp Bug Band on the trunk of the tree, to prevent the worms 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.