Ginseng is any one of 11 species of slow-growing perennial plants with fleshy roots, belonging to the genus Panax of the family Araliaceae. Ginseng is found only in the Northern Hemisphere, in North America and in eastern Asia (mostly Korea, northeastern China, Bhutan, and eastern Siberia), typically in cooler climates. Panax vietnamensis, discovered in Vietnam, is the southernmost ginseng known. This article focuses on the series Panax ginsengs, which are the adaptogenic herbs, principally Panax ginseng and P. quinquefolius. Ginseng is characterized by the presence of ginsenosides. Siberian ginseng is in the same family, but not genus, as true ginseng. Like ginseng, it is considered to be an adaptogenic herb. The active compounds in Siberian ginseng are eleutherosides, not ginsenosides. Instead of a fleshy root, Siberian ginseng has a woody root.