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At the first sign of greenworms 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 worms from migrating from the ground up towards the tree’s leaves.
In the early spring, use Once-A-Year Insecticidal Drench w/Merit to treat trees that are too tall to spray, to provide insect protection throughout the growing season.