Rumours of its amazing properties gradually spread.And today the yartsa gunbu is a passport into a shady,underground world. It's possible to dig up 40 of them in a day,the proceeds from which may provide half the collector's annual income. Yartsa gunbu has been used as a traditional remedy for thousands of years,though only by the very wealthy.It has been bartered for tea and silk,and is worth more than four times its weight in silver.So lucrative is this trade,that sites and information are jealously guarded.

 

At the nearby market,the yartsa gunbu are cleaned,and their true nature becomes clear. The yartsa gunbu translates summer grass,winter worm.The winter worm is a caterpillar.It eats roots of grasses in preparation for its transformation into a moth.But some winter worms never make it as moths.Instead,a strange growth erupts from their body,appearing above ground in summer.

 

This is the summer grass,a fungus called Cordyceps,whose spores have infected the caterpillar,using its body as their host. Modern scientific tests have shown that substances contained in Cordyceps lower blood pressure and make it easier to breathe.So in recent years,harvesting this natural treasure has grown into a huge and profitable business.