It's a colorful world, especially during autumn when leaves are changing from green to yellow, orange, brown and red.
Some leaves even turn purple.
It's all because of chemical pigments in the leaves. And it's the varying amounts of these pigments that create the colors. It is the green pigment in the leaves. During the spring and summer when trees are growing, nutrients continually add chlorophyll to the leaves. Because the dominant pigment is green, so are the leaves.