The growing popularity of herbal medicine, particularly in Western countries, is threatening the survival of a number of valuable wild plants, according to delegates to the U.N. Convention on International Trade in Endangered Species, meeting in Nairobi, Kenya, this week. Trade in at least 14 plants is already regulated because demand for herbal medicine is putting pressure on the species, and another six, including Asian ginseng, are being considered for regulation. Up to 600 kilograms of Asian ginseng are smuggled each year out of Russia, one of the few places where the plant grows. Illegal gathering of North American ginseng is also a problem. Poachers recently cleaned out all the healthy wild ginseng populations in the Great Smoky Mountains National Park in Tennessee and North Carolina.