Since the dawn of human civilization, forests have provided us with food, resources, and energy. The history of human development is also one of forest loss and transformation, and yet even in our increasingly urbanized societies we remain surprisingly dependent on forests for a wide range of goods and services. Moreover, forests still retain a remarkable hold on our environmental values. In an era of continuing tropical deforestation and temperate forest resurgence, and in the midst of uncertainties of climate and land use changes, it is more important than ever to understand what forests...