Maple Leaves About to Fall
The next rain or brisk breeze will strip these leaves from the tree and leave it ready for winter. This is a wild maple growing in Pennsylvania, USA so the wet fall weather has already started the decay process. Most of the Chlorophyll green is gone, there is lots of red, and some yellow. There are already spots where mold and fungi are starting to digest parts of the leaves.
All of this is part of the natural process that returns nutrient to the soil and makes them available for the coming spring.
