The Mu Us Desert, one of China's four major deserts, covers an area of 42,200 square kilometers, which used to be completely devoid of trees and farmland. From 1959 onward, local people planted trees to curb the invasion by sandstorms, extending the green area 400 kilometers northward after years of effort. Today, the desert has vanished from the map as 93 percent of the land undergoing desertification has become green.