No, there is no luminosity, only a little bit of translucency on the leaves. I know what you mean, the trees look a little bit flat, but also without translucency it doesn't look correct.
There are two kinds of broadleaf trees and two kinds of palmtrees, each with slightly different colours. I know, there could be even more variation, but I'll probably won't rerender the whole thing. Maybe I'll do some test renders.