1493: Uncovering the New World Columbus Created

by Charles C. Mann

  Move Hills, Fill Gullies and Create Plains!

  Destroy Forests, Open Wastelands!

  In Agriculture, Learn from Dazhai!

  Filled with excitement, lashed on by local authorities, villagers fanned out across the hills, cutting the scrubby trees on the pitches, slicing the slopes into earthen terraces, and planting what they could on every newly created flat surface. Despite heat and hunger, people worked all day and then lighted lanterns and worked at night. The terraces converted unplantable steep slopes into new farmland. In one village that I visited farmers increased the area of cultivable land by about 20 percent, which seems typical.

  Dazhai is in a geological anomaly called the Loess Plateau. For eon upon eon winds have swept across the deserts to the west, blowing grit and sand into central China. Millennia of dust fall have covered the region with vast heaps of packed silt—“loess,” geologists call it—some of them hundreds of feet deep. The Loess Plateau is about the size of France, Belgium, and the Netherlands combined.

  Loess doesn’t form soil so much as pack together like wet snow. For centuries, people in the plateau have dug caves in the loess and lived in them. Yaodong, as these cave dwellings are called, are quite cozy—the one I stayed in had a heated platform bed cut from a block of loess. An adjacent woodstove vented through the platform, warming the bed in winter. Looking at the yaodong walls that night, I realized that the room, like a scientific probe, revealed the earth’s workings. As a rule, soil has three layers: a thin scrim of dead leaves, bits of wood, and other organic matter on top; a band of dark topsoil, usually no more than a foot deep, shot through with humus (partly decomposed organic matter); and a stratum of subsoil below, lighter colored but rich with iron, clay, and minerals. Loess is different; my bedroom walls, carved from a giant heap of mashed-together grit, were uniform from top to bottom.

  As every child who plays with mud knows, dust piles are easy to wash away. Silt grains “act like single particles,” said Zheng Fenli, a soil scientist at the Institute of Soil and Water Conservation, in the Loess Plateau city of Yangling. They don’t clump together firmly. If knocked free by flowing water, Zheng told me, silt grains “are very easy to transport.” Washed down steep hills, they can be carried great distances. The Huang He makes a big loop right through the Loess Plateau. It carries an enormous burden of silt—more than any other river in the world—into the North China Plain, China’s agricultural heartland.

  Because the plain is flat, the river slows down. As the current falters, the silt in the water deposits on the river bottom and along the banks. The silt replenishes the soil—a main reason for the area’s farming primacy—but it also builds up the riverbed. In consequence, the Huang He rises one to three inches a year. Over time, it has lifted itself as much as forty feet over the surrounding land. When farmers harvesting wheat fields want to see the river, they look up. Moving high in the air, the river wants (so to speak) to overflow its banks, spilling into the North China Plain and creating a ruinous flood.

  Such disasters have been a threat for millennia—“two breaks every three years and a channel change every century,” the Chinese used to say of the Huang He. But in the eighteenth and nineteenth centuries, erosion drove the breaks and channel changes to be more lethal. In an attempt to subdue the floods, the Qing established a corps of engineers who maintained a five-hundred-mile line of dikes, a network of spillways, locks, and dams, and an array of as many as sixteen secondary channels into which the river could be divided—a hydraulic infrastructure easily as impressive as the Great Wall, and one that was more important to the life of the nation. Not only did the system control a staggeringly complex irrigation network, it connected the river to the Grand Canal, a 1,103-mile passage between Beijing and Hangzhou (a port south of modern Shanghai) that is the longest artificial waterway in the world. Qing emperors may have spent 10 percent or more of the imperial budget on the Huang He.

  Nonetheless the system was constantly overwhelmed. As the Chinese weather bureau maps show, excess silt made the Huang He spill over its banks a dozen times between 1780 and 1850—about once every six years. All of the floods were huge. One deluge in 1887 was among the deadliest ever recorded; estimates of the dead range up to a million.

  The cause of the flooding—deforestation in the Loess Plateau—was well understood. But Beijing did little about it, even though much of the land clearance had its roots in Qing policies, and the floods were blows to imperial legitimacy. The court’s failure to act was not foreordained. Neither was the myopia of the landlords who rented to the shack people. Nobody will ever know whether decisive action could have resolved the nation’s ecological problems, because it wasn’t tried. Instead the floods continued until the dynasty fell, an event the floods had helped to bring about.

  Which made it all the more incredible when Mao Zedong ordered more land clearing in the Loess Plateau. Most of the region was already deforested, but the steepest slopes—land too steep to farm—were still covered by low, scrubby growth that held back erosion. Exactly this land was targeted in the 1960s and 1970s for conversion, Dazhai style, into terraces. The terrace walls, made of nothing but packed earth, constantly fell apart; in one Loess Plateau village that I visited after a rainfall, half the population seemed to be shoring up crumbling terraces by pounding the walls flat with shovels. Even when the terraces didn’t crumble, rains sluiced away the nutrients and organic matter in the soil. Zuitou, the village, is nestled into steep hills along the Huang He. Walking along the steep paths between yaodong, I could almost watch the terraces sliding into the water.

  Because erosion removed nutrients, harvests in the newly planted land dropped quickly. To maintain yields, farmers cleared and terraced new land, which washed away in turn—a perfect example of a “vicious circle,” according to Vaclav Smil, a University of Manitoba geographer who has long studied China’s environment (his first book on the subject, The Bad Earth, appeared in 1984). Erosion into the Huang He went up by about a third during the Dazhai era, Chinese researchers reported in 2006.

  The consequences were dire and everywhere apparent. Declining harvests on worsening soil forced huge numbers of farmers to become migrants. Zuitou lost half of its population. “It must be one of the greatest wastes of human labor in history,” Smil told me. “Tens of millions of people being forced to work night and day, most of it on projects that a child could have seen were a terrible stupidity. Cutting down trees and planting grain on steep slopes—how could that be a good idea?”

  Beginning in the 1960s, farmers throughout China’s Loess Plateau stripped the forest and carved earthen terraces out of the hills. (Photo credit 5.1)

  Because the loess erodes easily, every rain caused terraces to erode maintenance was a constant issue. (Photo credit 5.6)

  Eventually the terraces on the steepest slopes collapsed completely, and farmers found themselves trying to eke out a living on hills almost too steep to stand on.

  In the most marginal areas farmers planted maize. North of Zuitou, at the edge of the Gobi Desert, I walked around plots of maize growing in almost pure sand. Until the 1960s the region had been covered with thorny forest scrub. Then Mao ordered aggressive planting. It was like forcing people to farm a beach. Astounding to me, the locals had actually coaxed some maize from the sand—drying cobs made little yellow heaps on rooftops and barren yards. On carts hauled by tiny Chinese motorbikes men were driving around piles of maize stalks tall as two-story buildings. In the light wind the air was intensely gritty. The Loess Plateau, which once caught dust from the desert, was now producing it.

  The People’s Republic had initiated plans to halt deforestation. In 1981 Beijing ordered every able-bodied citizen older than eleven to “plant 3–5 trees per year” wherever possible. Three years before, Beijing had initiated what may be the planet’s biggest ecological program, the “Three Norths” project: a 2,800-mile band of trees running like a vast screen across China’s north, northeast, and northwest, including the frontier
of the Loess Plateau. Scheduled to be completed in 2050, this Green Wall of China will, in theory, slow down the winds that drive desertification and dust storms.

  Despite their ambitious scope, these efforts did not directly address the soil degradation that was the legacy of Dazhai. Confronting the destruction was politically difficult, though: it had to be done without admitting that Mao had made mistakes. (When I asked local officials if the Great Helmsman had erred, they politely changed the subject.) Only in the last decade did Beijing chart a new course.

  Today many of the terraces Zuitou’s farmers hacked out of the loess are reverting to nature. In what locals call the “3-3-3” system, farmers replant one-third of their land—the steepest, most erosion-prone slopes—with grass and trees, natural barriers to erosion. They cover another third of the land with harvestable orchards. The final third, mainly plots on the gully floor that have been enriched by earlier erosion, is cropped intensively. By concentrating their limited supplies of fertilizer on that land, farmers can raise yields enough to make up for the land they have sacrificed—that’s the theory, anyway. To help the transition along, farmers are compensated with an annual delivery of grain and a small cash payment for up to eight years. By 2010, the program covered more than 56,000 square miles of gully villages, an area the size of Iowa.

  At first glance, it seems that a dictatorship would be perfectly suited to accomplish this task. The government can simply order loess dwellers to stop growing millet and plant almonds without worrying about property rights or political protest. It can direct whole villages to go into the hills en masse and plant saplings, millions upon millions of them, in small pits shaped like fish scales. And when the farmers and fields are shifted around, the planners can point to their accomplishments with pride.

  Things look different on the ground. Provincial, county, and village officials are rewarded if they plant the number of trees envisioned in the plan, not whether they have chosen tree species suited to local conditions (or listened to scientists who say that trees are not appropriate for grasslands to begin with). Farmers who reap no direct benefit from their work—they are installing trees that do not produce fruit, cannot be cut for firewood, and supposedly stop erosion miles from their homes—have little incentive to take care of the trees they are forced to plant. The entirely predictable result is visible on the back roads of Shaanxi: fields of dead trees, each in its fish-scale pit, lining the roads for miles. “Every year we plant trees,” the farmers say, “but no trees survive.”

  During my visit the lines of dead trees dotted the slopes like contour marks, stretching for miles. The harvest was over, and farmers were about to be marched back in for another try. Tree by tree, the government was trying to undo the accidental legacy of the global silver trade.

  1 The reader will have noted that I barely mention Dutch and Portuguese trade in Asia, which centered on spices, and focus on Spain and the galleon trade. This is partly to simplify a complex narrative, but mainly because the Spanish empire, the first truly global enterprise, is more germane to this book. In addition, the Netherlands and Portugal were entangled with that empire: the former not wresting full independence from it until 1648; the latter, long independent, forced by dynastic mishaps to accept a Spanish king from 1580 to 1640.

  2 Chen was not the only sweet-potato smuggler. According to a nineteenth-century gazetteer, the Chinese doctor Lin Huailan successfully treated a sick Vietnamese princess in 1581. At a banquet in his honor, he was served sweet potatoes. Vietnam had banned exporting the tuber to China “on penalty of death,” the gazetteer recounted, but Lin decided to take some anyway. “While crossing the border, he was questioned by a [Vietnamese] border official. Lin answered truthfully, and requested that the officer secretly let him through. The officer said: ‘As for what happens today, being a servant of the country, it would be disloyal of me to let you pass; however, being grateful for your virtues, to deny you would be unrighteous.’ He then drowned himself. Lin returned, and the tuber spread across Guangdong.”

  3 The ethnic group generally indicated by the word “Chinese” is the Han. The Manchu were pushing Han from the Chinese core into peripheral areas settled by other peoples.

  4 Agriculture was not the only cause of deforestation. China consumed huge quantities of timber as fuel and building material. To get the wood, platoons of workers went to distant places, where they wiped out entire forests. Alas, so much lumber was lost, damaged, and stolen during shipping, reported Yang Chang, a historian in Hubei Province’s Huazhong Normal University, that less than 2 percent of it was actually used by its intended recipients.

  PART THREE

  Europe in the World

  6

  The Agro-Industrial Complex

  POTATO WARS

  When potato plants bloom, they send up five-lobed flowers that bob in fields like fat purple stars. According to tradition, Marie Antoinette liked the blossoms so much that she put them in her hair. Her husband, Louis XVI, supposedly put one in his buttonhole, inspiring a brief vogue in which the French aristocracy swanned around with potato plants on their clothes. Potatoes belong to the nightshade family, which means they are cousins to tomatoes, eggplant, tobacco, sweet peppers, and deadly nightshade. The tubers are not roots but modified stems that store nutrients underground; the eyes, from which new potatoes sprout, are descended from the leaves that grew on the stem. Potato fruits look like green cherry tomatoes but are full of solanine, a poison that is part of the plant’s defense system—it prevents pests from eating the seeds. As a rule modern farmers ignore the seed, instead cutting up tubers and planting the pieces. In a testament to linguistic confusion, tubers used for this purpose are called “seed potatoes.”

  Today the potato is the fifth most important crop worldwide, surpassed in harvest volume only by sugarcane, wheat, maize, and rice. Originally it came from the Andes—not only Solanum tuberosum, the potato found in supermarkets, but many other types of potato that are eaten only in Ecuador, Peru, and Bolivia. There are also scores of wild potato species that can be found everywhere from Argentina to the southwestern United States. Despite similarities of name and appearance, not one of these potatoes is related to the sweet potato, which belongs to a different botanical family. The two have long been confused; the word “potato” is derived erroneously from batata, the Taino name for sweet potato (and the source of its scientific name, Ipomoea batatas). The mix-up rankled the early English botanist John Gerard, who complained in 1597 that “those [who] vulgarly impose names upon plants have little either judgement or knowledge of them.” Intending to clear up the matter definitively in his “generall historie of plantes,” Gerard used the term “Virginia potato” for the ordinary potato, which is not from Virginia. He called sweet potatoes “common potatoes.”1

  Potatoes are about three-quarters water and one-quarter starch but have vitamins enough to prevent scurvy if consumed in quantity. For 167 days in 1925 two Polish researchers ate almost nothing but potatoes (mashed with butter, steamed with salt, cut with oil into potato salad). At the end they reported no weight gain, no health problems, and, improbably, “no craving for change” in their diet. Historically speaking, the scientists’ regimen was not extreme; two British inquiries in 1839 intimated that the average Irish laborer’s per capita daily consumption of potatoes was twelve and a half pounds. Ireland was notorious for its potato habit, but the tubers had become so essential to all of northern Europe that Prussia and Austria fought a “potato war” in 1778–79 in which the two armies spent most of their time scrambling to get food for themselves and deny it to the enemy. Only when every potato in Bohemia had been consumed did hostilities end.

  Compared to grains, tubers are inherently more productive. If the head of a wheat or rice plant grows too big, the plant will fall over, with fatal results. Modern plant breeders have developed wheat and rice varieties with shorter, stronger stalks that can bear heavier loads of grain. But even they could not support something as heavy as an Ida
ho potato. Growing underground, a tuber is not limited by the rest of the plant—there are no worries about its architecture. In 2008 a Lebanese farmer dug up a potato that weighed nearly twenty-five pounds. Photographs showed a man holding a tuber bigger than his head.

  Many scholars believe that the introduction of S. tuberosum to Europe was a key moment in history. This is because their widespread consumption largely coincided with the end of famine in northern Europe. (Maize, another American crop, played a similar but smaller role in southern Europe.) More than that, the celebrated historian William H. McNeill has argued, S. tuberosum led to empire: “[P]otatoes, by feeding rapidly growing populations, permitted a handful of European nations to assert dominion over most of the world between 1750 and 1950.” Hunger’s end helped create the political stability that allowed European nations to take advantage of American silver. The potato fueled the rise of the West.

  As important in the long run, the European and North American adoption of the potato set the template for modern agriculture—the agro-industrial complex, as it is sometimes called. Celebrated by agronomists for its bounteous harvests and denounced by environmentalists for its toxicity, the agro-industrial complex rests on three pillars: improved crops, high-intensity fertilizers, and factory-made pesticides. All three are entwined with the Columbian Exchange, and with the potato.