Much of China's natural vegetation has been replaced or altered by thousands of years of human settlement, but isolated areas still support one of the world's richest and most varied collections of plants and animals. Nearly every major plant found in the tropical and temperate zones of the northern hemisphere can be found there. In all, more than 7,000 species of woody plants have been recorded, of which there are 2,800 timber trees and over 300 species of gymnosperms. The rare gingko tree, cathaya tree, and metasequoia, long extinct elsewhere, can still be found growing in China. Among flowering plants, 650 of the 800 known varieties of azalea occur in China, while 390 of the 450 known varieties of primrose and about 230 of the 400 known varieties of gentian are also found there. The tree peony, which originated in Shandong Province, appears in 400 varieties.
The richest and most extensive needle-leaf forests occur in the Greater Hinggan ling (Khingan) Mountains of the northeast, where stands of larch, Asian white birch, and Scotch pine flourish, and in the Lesser Hinggan ling (Khingan) Mountains, with stands of Korean pine and Dahurian larch. In the Sichuan (Szechuan) Basin, vegetation changes with altitude to embrace a variety of conifers at high levels, deciduous trees and cypresses at middle elevations, and bamboo in lower elevations. Farther south, in subtropical Fujian and Zhejiang provinces, broadleaf evergreen forests predominate. Forests give way to natural grasslands and scrub in drier western and northwestern areas, especially in the semiarid regions of Shanxi and Shaanxi, in the steppes of Inner Mongolia, and along the desert margins of the Tarim and Junggar basins.
China's most celebrated wild animal is the giant panda, a rare mammal now found in the wild only in remote areas of Sichuan, Gansu, and Shanxi provinces; as of 1994, just over 500 wild pandas were still in their natural state. Other fauna unique to China include the golden-haired monkey, found in remote parts of Shaanxi, Gansu, Sichuan, Guizhou, and Yunnan; the northeast China tiger, found in the Lesser Hinggan ling and Changbai mountains along the Korean border; the Chinese river dolphin and Chinese alligator, both found along the middle and lower Yangtze River; the rare David's deer and the white-lipped deer, the latter found mainly in Qinghai Province and Tibet; a rare kind of white bear found in Hubei Province; and the lancelet, an ancient species of fish representing a transitional stage between invertebrate and vertebrate development, now found only in Fujian Province. In addition, more than 1,000 species of birds have been recorded. Among the rarer kinds are the mandarin duck, the white-crowned long-tailed pheasant, golden pheasant, Derby's parakeet, yellow-backed sunbird, red-billed leiothrix, and red-crowned crane.