Cordyceps pickers search the ground on a frozen section of a river in a valley in the Amne Machin range in China's western Qinghai province, June 9, 2019. Cordyceps harvest has waned in Qinghai, the biggest producing region in China. One reason: higher temperatures, less seasonal snow, and receding glaciers have led to warmer mountains, making it less hospitable for the fungus, which thrives in soils that are cold but not frozen, about 5 degrees Celsius. REUTERS/Aly Song SEARCH "CHINA FUNGUS" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.