China is also one of the countries with the most abundant plant life in the world. There are more than 32,000 species of higher plants, and almost all the major plants that grow in the northern hemisphere's frigid, temperate and tropical zones are represented in China. In addition, there are more than 7,000 species of woody plants, including 2,800-odd tree species. The metasequoia, Chinese cypress, Cathay silver fir, China fir, golden larch, Taiwan fir, Fujian cypress, dove-tree, eucommia and camplotheca acuminata are found only in China. The metasequoia, a tall species of arbor, is considered to be one of the oldest and rarest plants in the world. The golden larch, one of only five species of rare garden trees in the world, grows in the mountainous areas in the Yangtze River valley. Its coin-shaped leaves on short branches are green in spring and summer, turning yellow in autumn. China is home to more than 2,000 species of edible plants and over 3,000 species of medicinal plants. Ginseng from the Changbai Mountains, safflowers from Tibet, Chinese wolfberry from Ningxia and notoginseng from Yunnan and Guizhou are particularly well-known Chinese herbal medicines. China has a wide variety of flowering plants; the peony, a flower indigenous to China and known as the "king of flowers" is characterized by large blossoms, multiple petals and bright colors, and is treasured as one of the country's national flowers.