Answer: If you have found just one or two caterpillars and can pick them off, that is all you would need to do. If there is a heavy infestation and the tree is losing a lot of foliage then you might want to consult with your local county extension to obtain a specific identification of the pest. Based on knowing that, they can tell you if it is something that requires a control or not. These trees are unfortunately potentially subject to a number of different diseases such as canker and pests as well. Your county extension can tell you which would be of most concern in your local area and whether or not a preventive spray program would be recommended. If so, they will have the most up to date information on what to use and how/when is best to apply it.
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