Cao Zhawa has been planting trees for most of his life. The ethnic Mongolian lives and works in the heart of Mu Us Sandyland, an area in the southwest part of Inner Mongolia Autonomous Region.

In 1958, when he was just 16 years old, Cao started planting trees under Chairman Mao Zedong’s afforestation program. Two decades later, during Deng Xiaoping’s reform and opening-up era, the program was renamed the “Three-North Shelter Forest Program,” and specifically tasked with planting trees and shrubs in areas threatened by desertification. Cao’s trees now cover an area of more than 1.3 million square meters, or the equivalent of 3,200 basketball courts.

According to the local forestry administration, Cao’s forest is worth an estimated 10 million yuan ($1.5 million) and can produce 100,000 kilograms of oxygen, enough to sustain a full-grown adult for nearly a year. However, Cao refuses to sell his trees, no matter how much he is paid. He said he will return the land to the state when he can no longer take care of it.

Mu Us Sandyland is one of the places in China most affected by erosion and desertification. The amount of annual precipitation ranges from 150 to 300 millimeters, while evaporation is between 2,000 and 3,000 millimeters. Cao recalls that growing up, his hometown in Inner Mongolia — located near the Gobi Desert — was plagued by sandstorms. “Sand was everywhere,” he said. “In my mouth, eyes, and ears.” This was one of the factors that motivated Cao to join and stay on in the tree-planting program.

Popularly known as the “Green Great Wall,” the project, which is set for completion in 2050, would be a 4,800-kilometer greenbelt of trees and shrubs protecting the area from strong winds and preventing soil erosion. Since the start of the Three-North Shelter Forest Program, millions of people have joined in and become a vital part of the initiative.

However, the tree-planters face a host of challenges, with watering foremost among them. “When I was young, the level of groundwater was high,” said Cao. “[But] with less rain, the trees are hard to plant and keep alive.”

Planting trees has also become harder for Cao as he ages. However, he doesn’t want to leave the forest in the care of his children, and he insists the land belongs to the government. “When I die, I just want to be buried under the trees,” Cao said. “Then I will be with them forever.”

Editor: Doris Wang.

(Header image: Cao Zhawa walks through a forest in Mu Us Sandyland, an area in the southwestern part of Inner Mongolia Autonomous Region, September 2017. Xu Haifeng for Sixth Tone)