Wither
When a tree grows old, it will wither.
Old trees' roots and leaves grow inefficient, and they can't get enough nutrients. It's only natural for them to wither up a little bit.
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This withered tree's best friend is a human 子 (こ). Imagine the child hugging the tree.
It gave the 子 its shade, its sap, and eventually its body to build a house. What an awful child, and what a generic giving tree.