Answer: When a tree loses 85% of its leaves it is in severe stress. This could be caused by many different reasons, but it is really not a good sign at all. The tree might have suffered root damage or trunk/bark damage, accidental exposure to chemicals such as herbicide, or there might be a pest or disease problem. If it was planted recently, perhaps it has not rooted into the surrounding soil the way it should have. I would suggest you work with your local Rutgers extension or possibly with a professionally trained and certified arborist to evaluate the tree and decide what to do. I hope it can be saved.
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