I love the fall color of sugar maples (A. saccharum of course), but find it annoying that so many of them color very unevenly. Some in my area have a single limb that colors a full month before the rest of the tree and ends up bare while the rest of the leaves are still green. Is this phenomenon more genetic to the tree, or is it based on environment?

Secondly, are there cultivars more likely to color more or less all at once in the fall, instead of having some branches nearly bare before other leaves have even shown much more than a hint of color?