For many plant lovers, winter seems like a lost time. The bursts of color and distinctive leaf shapes disappear, leaving what seems like ambiguous branches. But there is no need for botanical enthusiasts to hunker down until spring. What we overlook as "dead trees" are simply shoots covered up for the season. If we look closer, we'll see that trees and shrubs have distinct shapes to their buds and twigs that allow them to be classified reliably in...