Vehicles line the road as people go to dig caterpillar fungus in Zadoi County, Northwest China’s Qinghai Province, May 16, 2016. The worm grass, known in China as "winter-worm summer-grass," is not really a plant. It forms when a parasitic fungus hijacks and then feeds off the bodies of ghost moth larvae that have burrowed into the alpine soil. It then pushes the remains of their bodies to the surface so the fungus can spread its spores. The mummified moths are a traditional Tibetan cure-all that is believed to help fight cancer and the aging process, as well as boost the immune system. Photo: China News Service

People dig caterpillar fungus in Zadoi County, Northwest China’s Qinghai Province, May 16, 2016. The worm grass, known in China as "winter-worm summer-grass," is not really a plant. It forms when a parasitic fungus hijacks and then feeds off the bodies of ghost moth larvae that have burrowed into the alpine soil. It then pushes the remains of their bodies to the surface so the fungus can spread its spores. The mummified moths are a traditional Tibetan cure-all that is believed to help fight cancer and the aging process, as well as boost the immune system. Photo: China News Service

Local people have their ID checked before digging for caterpillar fungus in Zadoi County, Northwest China’s Qinghai Province, May 16, 2016. The worm grass, known in China as "winter-worm summer-grass," is not really a plant. It forms when a parasitic fungus hijacks and then feeds off the bodies of ghost moth larvae that have burrowed into the alpine soil. It then pushes the remains of their bodies to the surface so the fungus can spread its spores. The mummified moths are a traditional Tibetan cure-all that is believed to help fight cancer and the aging process, as well as boost the immune system. Photo: China News Service

People dig caterpillar fungus in Zadoi County, Northwest China’s Qinghai Province, May 16, 2016. The worm grass, known in China as "winter-worm summer-grass," is not really a plant. It forms when a parasitic fungus hijacks and then feeds off the bodies of ghost moth larvae that have burrowed into the alpine soil. It then pushes the remains of their bodies to the surface so the fungus can spread its spores. The mummified moths are a traditional Tibetan cure-all that is believed to help fight cancer and the aging process, as well as boost the immune system. Photo: China News Service

Every year from May to August, the bulk of the cordyceps harvest takes place. This year, as usual, tens of thousands of people from Litang County in the Garze Tibetan Autonomous Prefecture in Sichuan province are setting up tents on high-altitude plateaus to begin their search for cordyceps. (Photo/SCOL.com.cn)

Every year from May to August, the bulk of the cordyceps harvest takes place. This year, as usual, tens of thousands of people from Litang County in the Garze Tibetan Autonomous Prefecture in Sichuan province are setting up tents on high-altitude plateaus to begin their search for cordyceps. (Photo/SCOL.com.cn)

Every year from May to August, the bulk of the cordyceps harvest takes place. This year, as usual, tens of thousands of people from Litang County in the Garze Tibetan Autonomous Prefecture in Sichuan province are setting up tents on high-altitude plateaus to begin their search for cordyceps. (Photo/SCOL.com.cn)

A service team organized by the local government provides various services like medical care to the villagers. In recent years, the local government has also introduced policies to regulate the cordyceps harvest. Diggers need to obtain certificates before they began their work. (Photo/SCOL.com.cn)

A service team organized by the local government provides various services like medical care to the villagers. In recent years, the local government has also introduced policies to regulate the cordyceps harvest. Diggers need to obtain certificates before they began their work. (Photo/SCOL.com.cn)

A service team organized by the local government provides various services like medical care to the villagers. In recent years, the local government has also introduced policies to regulate the cordyceps harvest. Diggers need to obtain certificates before they began their work. (Photo/SCOL.com.cn)