The cartoon about the real reason leaves change color left out an important point (to some of us).

When the tree sends the nutrients from the leaves to the branches, they actually ship those nutrients farther down - to the roots. In many trees, the roots contain several species of fungi which helps supply the tree with water and important nutrients from the soil, all year long. But when the trees sends the photosynthetic nutrients down to the roots (late summer and fall), the fungi get a big shot of energy, which they promptly put into reproduction (which is always a good use of energy....!).

And up pops the mushrooms that we see every fall, after a rain. These fungi are known as mycorrhizal fungi. They produce many of the delectable mushrooms we harvest in the fall, including chanterelles and king boletes.

This has nothing to do with AHFMD, but interesting nonetheless....