The anthocyanins temporarily color the edges of some of the very young leaves as they unfold from the buds in early spring. They also give the familiar color to such common fruits as cranberries, red apples, blueberries, cherries, strawberries, and plums. In our autumn forests they show up vividly in the maples, oaks, sourwood, sweetgum, dogwood, tupelo, black gum, and persimmon. These same pigments often combine with the carotenoids' colors to give us the deeper orange, fiery reds, and bronzes typical of many hardwood species. The transparent waxy layer admits sunlight while preventing evaporation of water from leaf cells.
Veins support the leaf, and carry water to the leaf and food back out into the rest of the tree.
Palisade cells on the leaf's upper surface, crowded on end, receive direct rays from the sun.