History
Caterpillar fungus has been used as medicine in the Chinese culture for hundreds of years. It was once believed that caterpillar fungus was actually a worm. Through further scientific studies, though, it was learned that it is actually a fungus that produces a fruiting body through the host of a dead caterpillar larva. The fungus' name in Chinese, Dong chong xia cao, translates to "winter worm, summer grass." Hence, in winter it is a worm, and it turns to a plant in summer.
Geography
The caterpillar larva lives predominantly underground in alpine grass and shrub lands. It thrives in the Tibetan plateau, which is an immensely large and elevated plateau in Central Asia and the Himalayas, and it flourishes in an altitude from 9,000 to 16,000 feet.
Preparation
In the past, caterpillar fungus was dried and ground into a powder or combined with other tonics for ingestion. Currently, the most average form of ingestion is drinking the broth from a duck stuffed with the caterpillar fungus then boiled. In the latter method, the broth is agreeable both in taste and aroma. More creative recipes include fungus candy sold in drugstores and at farmers' markets.
Function
Traditionally, it is believed that ingesting the caterpillar fungus can aid in healing such ailments as coughs, anemia, and knee and back pain. Today, though, it is mainly used to relieve stress or to increase strength and vitality.
Considerations
Many local Tibetan farmers profit from harvesting caterpillar fungus and selling it to markets. Caterpillar fungus is sold in all drugstores in China as commonly as ginseng. Because of the potential profit, many resident and non-resident farmers are charged collection fees. A few counties have even begun to ban outsiders from collecting caterpillar fungus altogether, and others are adopting the same law.