Caterpillar fungus is carefully brushed and cleaned of soil. TENZIN NYIDA/XINHUA

In the high-altitude valleys of Nagchu, Xizang autonomous region, the first light of summer reveals a scene unchanged for generations: herders traversing snow-flecked slopes, their eyes trained to spot the precious medical ingredient of the plateau — caterpillar fungus (cordyceps sinensis). Known for its rarity and medicinal value, this prized organism thrives in the thin air of the Himalayas, with altitudes between 3,500 and 5,000 meters.

Now, as Nagchu implemented its first local regulations to protect and manage the caterpillar fungus sector on May 1, this year's harvest season in Sog county is balancing age-old traditions with modern ecological stewardship.

As the major income for local herders and farmers, the fungus accounts for up to 80 percent of their total income in Nagchu, Xizang autonomous region. TENZIN NYIDA/XINHUA

The city is a key site for the expensive ingredient in traditional Chinese medicine. The harvest season lasts 45 days. For local herdsmen, collecting this precious fungus offers them seasonal jobs and increases their income.

Each dawn, local herders fasten cloth sacks to their waists and ascend the mountains with small hoes. The fungus reveals itself only through a faint brown tip protruding from the soil, barely visible against the alpine meadows. For hours, they crawl on hands and knees, scanning the ground inch by inch.

The fungus is a key ingredient in traditional Chinese medicine. TENZIN NYIDA/XINHUA

Fungus diggers use an ice pick to prod the earth and dig a hole about 10 centimeters deep. After plucking the fungus from the soil, the diggers fill up the hole with the removed earth to restore the natural soil structure for fostering caterpillar fungus in the coming year. During this period, the herdsmen make their home temporarily in tents in the valley.

This year, however, the hunt is different. New rules require herders to obtain permits, designating approved areas and seasonal windows to prevent over-harvesting.

A herder crouches in the alpine meadows of Sog county in Nagchu, Xizang, searching for caterpillar fungus under the snow-dusted mountains. The fungus is also known as the "soft gold" of the plateau for its rarity and medicinal value. TENZIN NYIDA/XINHUA

Local officials and police patrol the mountains daily, ensuring compliance and safety in the remote terrain.

Sustainability is at the core of the regulations, aiming to protect the fragile ecosystem that sustains both the fungus and the region's biodiversity.

Local herders fasten cloth sacks to their waists and ascend the mountains with small hoes. TENZIN NYIDA/XINHUA

For herders, caterpillar fungus has been a major contribution to their annual income. The local authorities established 273 checkpoints and 475 temporary branches, ensuring a season free from resource disputes and criminal incidents, thereby maintaining social stability.

In last year's harvest season, more than 158,000 people collected the fungus at a total weight of 29,900 kilograms at 891 sites across six counties, according to the official statistics.

Police officers introduce designated areas for fungus collection to herders in Sog county. TENZIN NYIDA/XINHUA

Based on the market average price of 140,000 yuan ($19,423) per kilogram, the annual average output value of Nagchu's caterpillar fungus was estimated at 4.19 billion yuan. This income accounts for up to 80 percent of the total income of farmers and herders in the production areas, providing a substantial boost to local incomes and contributing significantly to regional economic development and social stability.

With the harvest season starting earlier this month, herders traverse snow-flecked slopes seeking the caterpillar fungus (cordyceps sinensis). TENZIN NYIDA/XINHUA

A bird's-eye view of a collection site in Nagchu. TENZIN NYIDA/XINHUA