In autumn, leaves get less sun and the green chlorophyll that trees use to absorb energy from sunlight (photosynthesis) breaks down into simpler compounds, which are stored in twigs for the winter. The lack of chlorophyll unmasks the yellow and orange pigments that were already in the leaves, but were concealed during the warmer months. The leaves are finally turning their true colors! The darker red leaves are largely due to sugars that get trapped and produce new pigments in some trees, like oaks, and dogwoods.
