Many might think of the typical Loess Plateau at the mention of Yan'an, a former revolutionary base of the Communist Party of China, in northwest China's Shaanxi Province. Twenty years ago, the city used to suffer from heavy sandstorms and floods. But now, these have become a thing of the past. Tremendous changes were possible thanks to China's "Grain for Green" program launched in 1999 in which farmers were called upon to convert their farmlands into forests.