I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
The symptoms on you maple point to root problems. You did a great job on everything you mentioned. I suspect soggy roots or possible too much fertilizer salts in the root zone are involved. There is no remedy now but to give it time and don't overwater. Hopefully it is in a bright spot but with plenty of shaded from the mid to late day sun. Otherwise the symtoms will likely get worse.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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