Why Do Leaves Turn Yellow or Red in Autumn?

Green Leaves contain various pigments, such as chlorophyll and xanthophyll. The chlorophyll is green while the xanthophyll, yellow. In spring and summer the quantity of chlorophyll surpasses other pigments and the leaves look green. in autumn the situation is reversed and the xanthophyll predominates, as a result the green leaves turn as yellow as gold. In autumn another pigment called anthocyanidin dominates in the leaves of some trees, such as smoke and maple. The anthocyanidin can make them look as red as fire.