File photo shows a member of the "cliff afforestation team" abseil down a cliff in Yichuan county, Yan'an city, northwest China's Shaanxi Province. (Photo courtesy of the interviewee)

At the crack of dawn, Wang Yonghong, head of the "cliff afforestation team" in Yichuan county, Yan'an city, northwest China's Shaanxi Province, begins his daily forest patrol. He covers more than 200 mu (about 13.33 hectares) of forest on foot each day.

Yichuan county sits in northern Shaanxi, a typical Loess Plateau region characterized by rolling hills and deep ravines. The 5-kilometer zone along the Yellow River suffers from severe drought and minimal rainfall, leading to serious soil erosion.

"When I was young, scooping water from the river meant half a basin of water, half a basin of sand," Wang Yonghong recalled, reflecting on the area's ecological fragility. "You could barely spot any trees in the mountains back then."

In 2004, when the county planned to reforest the rocky mountains along the Yellow River, 29-year-old Wang Yonghong volunteered for the mission, recruiting team members to participate in the ecological restoration project of the Yellow River Basin.

The upper part of this combo photo shows barren cliff faces along the Yellow River in Yichuan county, Yan'an city, northwest China's Shaanxi Province, while the lower part of the combo photo shows lush and verdant Yellow River cliffs. (People's Daily Online/Bai Ge)

Through years of persistent effort, the barren loess atop the mountains gradually gave way to lush greenery, but the bare cliffs below remained Wang Yonghong's nagging concern.

In 2012, the county decided to tackle the cliff reforestation challenge head-on. Wang Yonghong, then in his prime, once again stepped up to lead the initiative. He established the "cliff afforestation team," and began experimental plantings of drought-resistant Chinese arborvitae on steep cliff faces.

Planting trees on the sheer Yellow River cliffs—compounded by thin soil layers, barren land, strong winds, and arid climate conditions—rendered traditional tree-planting methods completely ineffective.

After countless attempts, Wang Yonghong and his team, working alongside forestry technicians, developed specialized cliff-planting techniques tailored to different conditions.

Wang Yonghong prepares seedlings to be transported by a drone in Yichuan county, Yan'an city, northwest China's Shaanxi Province. (People's Daily Online/Bai Ge)

He recalled the early afforestation operations: with transport vehicles unable to access the sites, team members first carried fertile soil and seedlings up the mountain on their backs, then used ropes to lower workers down cliff faces to dig holes, fill soil, and plant trees.

Last spring, the "cliff afforestation team" deployed plant protection drones for the first time to assist with seedling transportation and tree planting, and invited experts to provide on-site guidance for drone operations.

"A single drone trip carrying seedlings and soil takes just three minutes. We save energy for actual planting, allowing one person to plant nearly 100 trees per day—that's what our entire team used to accomplish in a full day," Wang Yonghong said.

This spring, 47-year-old forester Wang Jianghong purchased a drone at his own expense and obtained a drone operator's license alongside teammate Hao Lei.

A drone carries seedlings to an afforestation site in Yichuan county, Yan'an city, northwest China's Shaanxi Province. (People's Daily Online/Bai Ge)

It is relentless determination that has enabled the team to create a green miracle across the Yellow River's cliff faces over 13 years. The survival rate of trees has exceeded 90 percent today, up from merely 40 percent at the initial phase of the team's mission.

Today, the team has expanded to more than 30 members, collectively planting over 10,000 mu of forest in ecologically fragile areas.

In Yichuan county, eight other professional afforestation teams work alongside the "cliff afforestation team."

As of 2024, Yan'an city's forest coverage rate had increased from 33.5 percent before the grain-for-green program to 53.07 percent, while vegetation coverage had risen from 46 percent to 81.3 percent.

File photo shows Hao Lei and a tree he planted in Yichuan county, Yan'an city, northwest China's Shaanxi Province. (Photo courtesy of the interviewee)

All the city's 13 counties and districts have been designated as state-level model counties for ecological progress.

"The tallest trees on the mountains now reach over 4 meters, while cliff-side trees grow more slowly, with the tallest reaching over 2 meters," Wang Yonghong said, adding that the team has already planted more than 1,000 mu of forest this year.

File photo shows members of the "cliff afforestation team" in Yichuan county, Yan'an city, northwest China's Shaanxi Province. (Photo courtesy of the interviewee)