Why do the leaves change color in Fall?
Most of autumn’s colors have actually been in the leaves all summer long, but hey were “covered up” by the dominant green of the chlorophyll. As the weather cools and shorter days settle in, the chlorophyll begins to break down, revealing new and varied color pigments. The brightest colors are seen when late summer is dry and autumn has sunny days and cool nights
Chlorophyll is responsible for helping trees and plants turn sunlight into food. For most months, is the dominant color seen here in most leaves until it fades away.
Unlike other leaf colors that always exist in the leaf, athocyanins are produced as the chlorophyll is broken down. The athocyanins are often seen in the leaves named for their red fall color, including red maples, scarlet oaks, and red sumacs.
Sugar maples may be one of the best examples of carotene in action. Their bright signature orange fills many hills and country roads throughout the northern US. As the name implies, carotenes are the chemical responsible for giving carrots their unique coloring.
Xanthophyll can be seen throughout the fall in beeches, ashes, birches, aspens, and some oaks. It also contributes its bright orange color to autumn squash and corn.