Answer: Cherries can be attacked by a number of caterpillars, borers, and other insects. The best defense is to keep the tree healthy and to avoid injuring the bark in any way. (Be especially careful when mowing or trimming near the trunk.) For a definite identification of the cocoon you found (it might not be a pest!) and the most up-to-date control recommendations, you might contact your County Extension at 989-6830.
If this is a new tree, be sure to water it regularly as needed for a full year until it is well established. A mulched area several inches thick beneath the tree can also help, although the mulch should be kept several inches away from the trunk. Finally, you might fertilize with a balanced granular fertilizer such as 10-10-10 according to the label instructions.
Enjoy your tree!
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