Answer: Based on the information and symptoms in your question, unfortunately I am not certain what is wrong with your tree. I would suggest you work with your local Cornell county extension to figure out what is happening to it and based on knowing that, decide how to take care of it. They might appreciate photos of the overall tree, closeups of the darkened bark area and also of the insects you are seeing. I'm sorry I can't be more specific for you long distance.
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