Answer: Based on your description I am not certain what is happening to your tree. It is possible that an underlying stress has eventually caught up to it, possibly something like being extremely rootbound. However you must have been taking good care of it and have a perfect spot for it if you have been able to keep it for ten years. I would suggest you consult with your local Cornell cooperative extension to see if by chance there is a pest problem that might be controlled. I hope you can save it!
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