If environmental and economic sustainability is ultimately a matter of balancing the human race’s consumption and productivity, then the agricultural industry leans heavily on both sides of that scale. Its drain on the earth’s resources is enormous: it claims 70 percent of all freshwater taken by our species and more than 40 percent of the planet’s solid surface (nearly all the arable land), with attendant casualties in bio­diversity. Yet modern agriculture is also the only reason we can produce enough food to nourish our population of 6.8 billion—a number slated to reach more than nine billion by midcentury. Keeping up with that steeply rising demand thus defines the challenge of sustain­ability not only for agriculture but for humanity.