1493_ Uncovering the New World Columbus Created - Charles C. Mann [118]
As the sweet potato and maize did in China, the potato (and maize, to a lesser extent) helped Europe escape Malthus. When the agricultural economist Arthur Young toured eastern England in the 1760s he saw a farming world that was on the verge of a new era. A careful investigator, Young interviewed farmers, recording their methods and the size of their harvests. According to his figures, the average yearly harvest in eastern England from an acre of wheat, barley, and oats was between 1,300 and 1,500 pounds. By contrast, an acre of potatoes yielded more than 25,000 pounds—about eighteen times as much.4 Growing potatoes especially helped England’s poor, Young believed. “It is to be wished, that all persons who have it in their power to render this root more common among them, would exert themselves in it.” Potatoes, he proclaimed, “cannot be too much promoted.”
Potatoes didn’t replace grain but complemented it. Every year, farmers left fallow as much as half of their grain land, to rest the land and fight weeds (they were plowed under in summer). Now smallholders could grow potatoes on the fallow land, controlling weeds by hoeing. Because potatoes were so productive, the effective result was, in terms of calories, to double Europe’s food supply. “For the first time in the history of western Europe, a definitive solution had been found to the food problem,” the Belgian historian Chris Vandenbroeke concluded. (The German historian Joachim Radkau was blunter: the key environmental innovations of the eighteenth century, he wrote, were “the potato and coitus interruptus.”) Potatoes (and, again, maize) became to much of Europe what they were in the Andes—an ever-dependable staple, something eaten at every meal. Roughly 40 percent of the Irish ate no solid food other than potatoes; the figure was between 10 and 30 percent in the Netherlands, Belgium, Prussia, and perhaps Poland. Routine famine almost disappeared in potato country, a two-thousand-mile band that stretched from Ireland in the west to Russia’s Ural Mountains in the east. At long last, the continent could, with the arrival of the potato, produce its own dinner.
Although the potato raised farm production overall, its greater benefit was to make that production more reliable. Before S. tuberosum, summer was usually a hungry time, with stored grain supplies running low before the fall harvest. Potatoes, which mature in as little as three months, could be planted in April and dug up during the thin months of July and August. And because they were gathered early, they were unlikely to be affected by an unseasonable fall—the kind of weather that ruined wheat harvests. In war-torn areas, potatoes could be left in the ground for months, making them harder to steal by foraging soldiers. (Armies in those days did not march with rations but took their food, usually by force, from local farmers.) Young’s interview subjects used most of their potatoes for animal feed. In bad years, they had been forced to choose whether to feed their animals or themselves. Now they didn’t have to make the choice.
The economist Adam Smith, writing a few years after Young, was equally taken with the potato. He was impressed to see that the Irish remained exceptionally healthy despite eating little else: “The chairmen, porters, and coal-heavers in London, and those unfortunate women who live by prostitution—the strongest men and the most beautiful women perhaps in the British dominions—are said to be, the greater part of them, from the lowest rank of people in Ireland, who are generally fed with this root.” Today we know