Stand under a tree and look up! In all seasons this affords an endlessly interesting moment. When leaves are on the trees, the play of light, shadow, and color—particularly in the fall—is dazzling. Start taking photographs. The images will have the uncentered energy of an oriental rug. A different kind of reward awaits you in winter. It takes greater effort, but as you look more and more attentively, the unique structure of each tree, like its skeleton, reveals itself. As do unfallen fruit, the last stubborn leaves, and abandoned nests.