If a tree falls in a forest and no one is around to hear it, does it make a sound? This question has engaged philosophers through the ages in discussions regarding observation and the knowledge of reality. Scientists in the PhenoCam Network are also interested in what goes on in forests when no one is around to observe them but are less interested in the presence or absence of noise as trees fall but in knowing the timing of when trees flower, leaf, or fruit. They have found a relatively simple and clever way to record what is going on with plants via a network of digital cameras, called PhenoCams, mounted on platforms at various locations around the world.