“But in the fall, because of changes in the length of daylight and changes in temperature, the leaves stop their food-making process.
The chlorophyll breaks down, the green color disappears, and the yellow to orange colors become visible and give the leaves part of their fall splendor.
At the same time other chemical changes may occur, which form additional colors through the development of red anthocyanin pigments.
Some mixtures give rise to the reddish and purplish fall colors of trees such as dogwoods and sumacs, while others give the sugar maple its brilliant orange.
The autumn foliage of some trees show only yellow colors. Others, like many oaks, display mostly browns.
All these colors are due to the mixing of varying amounts of the chlorophyll residue and other pigments in the leaf during the fall season.” (College of Environmental Science and Forestry)
The autumn leaf color change can be given a description both prosaic or poetic and scientific or sentimental. The beauty is neither hard to picture or imagine. The season comes with its own unique scents and has a particular climatic feel to it. The year is winding down, nature is getting sleepy, getting ready for its blanket of snow. The burst of color is a delight to the eyes, even if its scientific cause is a bit dull.
You can find other photos I took of the fall color change at Autumn 2018 or Early Autumn.