Autumn Leaf Cross Section

There are three major components for autumn pigment change in leaves. Plastids are minute leaf structures that carry green chlorophyll and color the summer forest. Carotenoids, stored in plastids, and anthocyanins in sap are the leaf paints (pigments) that color the fall forest. Here is a brief overview of a tree leaf while undergoing autumnal color change. The color change and then leaf fall is explained in detail including a great USFS illustration.