When early summer greets the Tibetan communities in northwest China's Qinghai Province, local herdsmen and farmers start heading for alpine soil over 4,000 meters above sea level. Here they spend weeks digging an expensive ingredient in traditional Chinese medicine - the caterpillar fungus.
As the high-altitude winds make for a brisk morning, these diggers, who climb up mountains early, can feel the thinness of the air in their lungs, but still exert themselves to find the tiny fungus.
Found only at high altitudes, the fungus, known in China as "winter-worm summer-grass," reputedly has cancer-fighting properties and boosts the immune system.
The caterpillar fungus gold rush, which takes place annually in many parts of China's Qinghai-Tibet Plateau, has brought wealth to many local herdsmen but also created ecological woes. In Qinghai's Yushu Tibetan Autonomous Prefecture, a major production area of caterpillar fungus, the fungus gold rush is undergoing quiet changes.
For more than a month from late May, the gold rush is in full swing in Yushu's Sanjiangyuan region, known as the source of the headwaters of the Yangtze, Yellow, and Lancang rivers.
For local herdsmen, it is the busiest and most exciting time of year to hunt down such fungus, an important source of income for many of them. It offers seasonal jobs for local herdsmen. Even schools are closed so that students and teachers can join in the harvesting.
The fungus forms when a parasitic fungus hijacks and then feeds off the bodies of ghost moth larvae that have burrowed into the alpine soil, 3,000 to 5,000 meters above sea level. The fungus then pushes the remains of their bodies to the surface so it can spread its spores.
It is so sought after in China for its medicinal qualities that it sometimes fetches its weight in gold.
"Digging the fungus is hard work. It needs good eyesight, physical strength and luck," said Tsewen, a herdsman from the Bagan township.
Lying on the alpine ground, trying to spot the tiny caterpillar fungus as small as an apple stalk, fungus diggers like Pema Khandro have to brave harsh climates from sunup till sundown.
Pema, 35, is no stranger to harvesting the fungus, with years of practice. After locating her target, Pema uses an ice pick to prod the earth and dig a hole about 10 centimeters deep. To keep the fungus intact, she then lifts a clump of earth and sifts out the fungus.
Back in the day, holes were all over the place after the fungus season, causing severe damage to the fertility of the land on which local herdsmen have been depending for their livelihoods for centuries.
Experts have warned that the cash cow may die out in two decades, if no measures were taken to reverse the overexploitation.
Like other fungus diggers, after carefully wrapping her trophy, Pema quickly fills in the pit and replenishes the turf before she moves on to her next target, to reduce the damage to the soil.
ALTERNATIVES FOR PROSPERITY
Herding is a mainstay industry in Yushu. However, local herdsmen had to deal with constant risks due to the region's harsh natural conditions, which accounts for their long-time dependence on the fungus gold rush.
In recent years, thanks to booming ecological animal husbandry, 206 cooperatives have been established in Yushu. Many herdsmen gathered their yaks together and the cooperatives are in charge of herding. Collectively they are stronger before natural disasters. With support from government in technology and funds, the cooperatives are more productive and efficient than individual herdsmen.
Nyima Dargye, who leads a cooperative in the Maxiu Village, said the cooperative has 60 herdsmen from 11 households. Besides the basic income from herding, each household of the cooperatives received nearly 10,000 yuan (about 1,425 U.S. dollars) as dividends last year, he said.
In recent years, with improved social security and more poverty-alleviation projects, the importance of the fungus economy has declined. "Digging caterpillar fungus always depends on the weather. It is hard and requires luck as well," Pema said. "With better policies, the herdsmen also have more income and we'll feel more at ease during the fungus season."
Beginning in 2005, China launched the country's biggest ecological project to protect and restore the environment in Sanjiangyuan. In 2016, China started piloting the Sanjiangyuan National Park.
"After the park went into trial operation, many herdsmen have been employed as ecological protectors, with each earning more than 20,000 yuan per year," said Kata with the park's administration department.
According to official figures, the park now employs 17,211 local ecological protectors.
As local herdsmen's revenues diversify, digging caterpillar fungus gold has lost its former glitter, and become a mere seasonal job to earn extra cash.
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