No risk is more terrifying than that taken by the first root. A lucky root will eventually find water, but its first job is to anchor -- to anchor an embryo and forever end its mobile phase, however passive that mobility was. Once the first root is extended, the plant will never again enjoy any hope (however feeble) of relocating to a place less cold, less dry, less dangerous. Indeed, it will face frost, drought, and greedy jaws without any possibility of flight. The tiny rootlet has only once chance to guess what the future years, decades -- even centuries -- will bring to the patch of soil where it sits. It assesses the light and humidity of the moment, refers to its programming, and quite literally takes the plunge.