“High-yield agriculture and long-distance trade have long delivered a similar outcome—more abundant and affordable food with reduced environmental impact—on a global scale…. So prepare your meal from the most affordable food you can find to do both your wallet and the planet a favor.”

The lessons of history can be very eloquent, if only we are willing to take the time to learn them. In a 2008 National Geographic article, journalist Charles Mann discusses how soil management policies in communist China led to the creation of terrace agriculture in unsuitable conditions, the cutting down of trees, and the planting of grain on steep slopes. The main results were increased soil erosion and soil depletion.

Daring to challenge official edicts, some villagers replanted the steepest and most erosion-prone third of their land with grass and trees, covered another third with harvestable orchards, and concentrated their crops on the remaining lower flat plots that had been enriched by the soil washed down from the hillsides.…