Chinese or oriental arborvitae, or ce bai [Chinese] (Fu et al. 1999).
The sole species in the genus Platycladus Spach 1842 (syn. Biota D. Don ex Endlicher).
Synonymy (Fu et al. 1999):
Monoecious evergreen trees to 20 m tall and 100 cm dbh. Bark red-brown to light grey-brown, thin, flaking in long strips. Crown ovoid-pyramidal when young, broadly rounded or irregular when old. Branchlets arranged in a plane, spreading or ascending, flattened. Leaves decussate, 4-ranked, scalelike, base decurrent, 1-3 mm long, apex bluntly pointed, with an abaxial resin gland, dimorphic along branchlets; lateral leaves overlapping facial ones, boat-shaped, ridged, apex slightly incurved, without conspicuous, white stomatal bands abaxially but with a median groove. Facial leaves rhomboid, with a conspicuous, linear, glandular groove at center abaxially. Pollen cones with 8-12 microsporophylls, each with 3-6 pollen sacs; yellowish green, ovoid, 2-3 mm long. Seed cones terminal, solitary, dehiscent when mature in first year, when immature bluish green, subglobose, ca. 3 mm in diameter, when ripe red-brown, subovoid, 1.5-2(-2.5) × 1-1.8 cm; cone scales 6 or 8, decussate, flat, thick, woody, only the middle 2 pairs fertile (proximal 2 fertile cone scales 2-seeded, distal 2 fertile scales 1-seeded); free bract apex a long, recurved cusp. Seeds wingless, rarely with a very narrow wing, grey-brown or purple-brown, ovoid or subellipsoid, 5-7 × 3-4 mm, slightly ridged. Cotyledons 2. Pollination March to April, seed maturity October (Fu et al. 1999).
Korea, E. Russia, and China. Natural occurrences in China are difficult to distinguish from local introductions, owing to extensive cultivation and planting in the past. It is native in S Gansu, Hebei, Henan, Shaanxi, Shanxi; introduced or status uncertain in Anhui, Fujian, N Guangdong, N Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, S Nei Mongol, Shandong, Sichuan, Xizang, Yunnan, and Zhejiang. Occurs at 300-3,300 m. elevation (Fu et al. 1999). Naturalized in Florida (Little 1980). Hardy to Zone 6 (cold hardiness limit between -23.2°C and -17.8°C) (Bannister and Neuner 2001).
One in Nasreddinabad, Tajikistan, is 35 m high and 14 m dbh (Vladimir Dinets e-mail 1998.01.10).
Ages of some cultivated trees in the Beijing (China) area are said to exceed 1000 years (Silba 1996).
"It is common tree of China, and some relic populations exist in Central Asia (it is often said that they are all along The Great Silk Road and aren't natural, but there are also some very old trees in remote mountain areas" (Vladimir Dinets e-mail 1998.01.10).
Franco. 1949. Portugaliae Acta Biol., ser. B, Sist. Vol. "J'lio Henriques": 33.
Silba, John. 1996. Noteworthy conifers in the Xian Shan region of Beijing, China. American Conifer Society Bulletin 13(1):8-12.
Spach, Rhoeadium. 1841. Histoire Naturelle des Végétaux. Phanérogames 11: 333.
Farjon (2005) provides a detailed account, with illustrations.
Last Modified 2012-11-28