Autumn brings with it a leaf transformation just as beautiful as when it first budded. The process of sealing off the leaves from the stem (called abscission) stops the production of chlorophyll in every leaf. This, in turn, stops photosynthetic green pigment development which allows other masked colors to be expressed. The unmasked leaf colors quickly become markers for identifying individual deciduous tree species and a very few conifers.
Let me introduce you to trees according to leaf color. I have prepared a photo gallery of popular fall foliage and a list of tree species listed by their primary colors.