Purple Leaves   Lee E. Frelich   Jun 23, 2006 12:24 PDT  Phil: Red to purple pigments are generally formed in a chemical reaction catalyzed by sunlight, so it makes sense that the red pigment is more concentrated on top of the leaf. There is chlorophyll inside the leaf which is visually masked by the red pigments. Red light is very important for photosynthesis, obviously some of that light is reflected, but it is likely that the most pigmented leaves at the top of the tree get 2 or 3 times as much sunlight as they can possibly use, so photosynthesis doesn't seem to be a problem for trees with red leaves. Leaves vary a lot from shaded leaves at the bottom of the crown (thinner and bigger, can harvest more sunlight, does not need much protection from wind and rain) to sun leaves at the top (thickest leaves, receive an excess of sunlight, high temperatures, wind and rain, need more strength). Lee   Lee,        I've been noticing more about the tree species that I've been measuring in Hartford, CT. There are a couple of European Copper Beech on the grounds, and I have some questions about the species. I've noticed that the tree's leaves are purple on the top and green underneath. I was wondering why that was. Wouldn't that interfere with the production of chlorophyll? These trees are quite squat and fairly tall so I know they're obviously getting what they need, regardless of the leaf coloring. When I picked up one of the leaves off the ground I was surprised at the texture. The leaf was waxy and seemed to be quite strong, not the limp and weak leaf I was imagining. What purpose does the strong leaf serve for this species? Phil   Home