Zhang Liubao returned from Dazhai to his home village of Zuitou full of inspiration. Zuitou was so impoverished, he told me, that people ate just one or two good meals a year. Following Zhang's instructions, villagers fanned out, cutting the scrubby trees on the hillsides, slicing the slopes into earthen terraces, and planting millet on every newly created flat surface. Despite constant hunger, people worked all day and then lit lanterns and worked at night. Ultimately, Zhang said, they increased Zuitou's farmland by "about a fifth"—a lot in a poor place.
Alas, the actual effect was to create a vicious circle, according to Vaclav Smil, a University of Manitoba geographer who has long studied China's environment. Zuitou's terrace walls, made of nothing but packed silt, continually fell apart; hence Zhang's need to constantly shore up collapsing terraces. Even when the terraces didn't erode, rains sluiced away the nutrients and organic matter in the soil. After the initial rise, harvests started dropping. To maintain yields, farmers cleared and terraced new land, which washed away in turn.
The consequences were dire. Declining harvests on worsening soil forced huge numbers of farmers to become migrants. Partly for this reason, Zuitou lost half of its population. "It must be one of the greatest wastes of human labor in history," Smil says. "Tens of millions of people forced to work night and day 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?"
In response, the People's Republic initiated plans to halt deforestation. In 1981 Beijing ordered every able-bodied citizen older than 11 to "plant three to five trees per year" wherever possible. Beijing also initiated what may still be the world'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 complete 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 that head-on was politically difficult: It had to be done without admitting Mao's mistakes. (When I asked local officials and scientists if the "Great Helmsman" had erred, they changed the subject.) Only in the past decade did Beijing chart a new course: replacing the Dazhai Way with what might be called the Gaoxigou Way.