Answer: I apologize for the delay in answering your question. I hope by now you have contacted your retailer for advice, especially if a warranty is involved. Japanese maples are very sensitive to soil conditions. They require a somewhat acidic soil that is humusy and organic, evenly moist yet well drained. This means damp like a wrung out sponge, not sopping wet or saturated, and never dried out. Based on your description, the symnptoms could be related to transplant shock if you just planted it in the heat of summer, soil conditions, over watering, under watering, or even overfertilizing having caused root damage. Unfortunately this type of problem is very difficult to diagnose long distance. I would strongly suggest you work wiht your retailer (since it is a new plant) and/or your county extension to try to determine what has happened and try to save the tree.
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