What Causes Fall Leaf Color

Why do leaves change color in the fall? From vivid reds to golden yellows, the science behind autumn's colors reveals how weather, tree species and chemistry combine to create the seasonal. Autumnal leaves in vibrant hues are a beautiful part of the season, but those leaves are also a vital part of keeping trees alive. Trees that have leaves that change color in fall are deciduous.

Leaves changing colors is one of the most iconic parts of autumn in the United States. But why do leaves change their color in the first place? Leaves change color during the autumn because the amounts of pigments change as the leaves prepare to fall from the trees.

All leaves gradually lose chlorophyll during the growing season, and this loss accelerates before leaf fall. Explore why leaves change color in fall, the role of sunlight and pigments, and top tips for spotting the brightest autumn foliage this season. In many places around the world, autumn is marked by the slow, beautiful change of green foliage to vibrant reds, oranges, yellows, and purples.

Learn why leaves change color in the fall and see the chemistry of the pigment molecules responsible for different leaf colors. The color of fall foliage depends on the tree species and the mixture of pigments in the leaf. There are three main pigments that give leaves their color and include chlorophyll, carotenoids, and anthocyanins.

In spring and summer chlorophyll is the pigment that gives leaves their green color. The color change culminates in leaf abscission, the shedding of leaves from the tree. This protective mechanism allows deciduous trees to conserve water and energy during winter.

In the fall, trees put on a pretty impressive fashion show. Leaves that were green all summer long start to turn bright red, orange, and yellow. But where do these colors come from? It all starts inside the leaf.

Leaves have color because of chemicals called pigments, and there are four main types of pigment in each leaf: Leaves are green in the spring and summer because that's when they are.