The leaves on trees are green because they contain chlorophyll. The leaf also has other colors, but they are hidden by the chlorophyll. The shorter days and cooler nights of autumn causes the chlorophyll in dedicuous broad leaves to break down.
The hidden colors of these leaves appear as the chlorophyll breaks down. The leaf then may show the yellow color of the pigment xanthophyll or the orange-red tones of the carotene pigments. A group of red and purple pigments called anthocyanins forms in the dying leaf. The color of the autumn leaf depends on which of the three pigments is most plentiful in the leaf.
I don't have to understand the science how the leaves change colors to enjoy the spectacular views!!
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