The effects of adverse economic conditions in U.S. agriculture upon the structure of farming have been given wide publicity. At the same time but less widely noted, a quiet revolution has taken hold of the ancillary industries supporting agriculture as they struggle to adapt to the changed...

Improving agricultural productivity has been the world’s primary defense against a recurring Malthusian crisis— where needs of a growing population outstrip the ability of humankind to supply food. Over the last half-century, world population doubled while food supply tripled, even as land...