Answer: The trunk decay you describe is caused by a fungal infection that usually enters through an injury. The most common injuries to the trunks of trees are caused by lawn mowers and string-trimmers. When the tender bark of a young tree is injured, fungal spores can attack. Maple trees are not especially adapted to your region; they require more humidity and moisture than you normally experience. Why not replace your young tree with one that will perform better for you? If you're looking for a shade tree, try Catalpa or Fruitless Mulberry. Both are rapid growers, reasonably pest free, and provide luxurious canopies to cast dense shade in the summertime.
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