Fungus gold rush on Tibetan plateau

Yushu is only slowly recovering from the 6.9 magnitude earthquake that struck on 15 April. The government has identified caterpillar fungus collection as one of three core activities to rebuild the local economy
Photograph: Jonathan Watts/Guardian

Most of the harvesting is done on spectacular hillsides like these
Photograph: Jonathan Watts/Guardian

At high-altitude, the work is gruelling. Collectors spend twelve hours a day scouring the slopes for the slim, small stem-like protuberances that that stuck out of the earth
Photograph: Jonathan Watts/Guardian

The earth remains damaged near the epicentre of the earthquake at Longbaozhen, one of the fungus harvesting areas
Photograph: Jonathan Watts/Guardian

With increasing numbers of people joining the lucrative harvest, locals say some areas have been picked almost empty. This has resulted in violent conflicts over territory – occasionally fatal
Photograph: Guardian

The long, slim fungus - known locally as Yartsa Gunbu (summer grass winter worm) - consumes its host, the ghost moth caterpillar, from inside out during the latter’s hibernation on the mountain grasslands
Photograph: Jonathan Watts/Guardian

Tibetan Buddhist monks outside a refugee tent in Yushu market joke as they sell caterpillar fungus. The fungus, Cordyceps sinensis, is prescribed as a cure for cancer and ailments of the liver and kidney in traditional medicine
Photograph: Jonathan Watts/Guardian

Along with the export of migrant workers and Tibetan mastiff breeding, it is a mainstay of family incomes
Photograph: Jonathan Watts/Guardian

Local women, employed to clean the dirt off of the fungi, can earn 100 yuan per day - a better income than most Chinese factory labourers
Photograph: Jonathan Watts/Guardian

A boy harvester show a freshly picked cordyceps. Depending on the size and quality, the fungi are sold here for 25 to 35 yuan each, or about 40,000 yuan per kilogram
Photograph: Jonathan Watts/Guardian

At the end of the retail chain in the big cities of Asia, rich consumers pay up to 360,000 yuan per kilogram for the best fungus – which is more than is paid for gold
Photograph: Jonathan Watts/Guardian