Description from Flora of China
Trees or shrubs to 50 m tall; trunk to 3 m d.b.h.; bark dark gray to dark brown, or reddish brown, longitudinally fissured, cracking into irregular flakes; crown pyramidal. Leaves glossy deep green adaxially, narrowly linear-lanceolate, straight or slightly falcate, 0.8-6.5(-7) cm × 1.5-5 mm, midvein green abaxially, 0.3-1.2 mm wide, flat with median longitudinal keel throughout, stomatal bands present on both surfaces, bands on adaxial surface 0.5-1.5 mm wide, of 7-28 rows of stomatal, white powdery or not, bands on abaxial surface 1.2-2.8 mm apart, 0.3-0.8(-1) mm from leaf margin, not or rarely white powdery, base decurrent, margin denticulate, sometimes indistinctly so, especially on old trees, with 18-55(-90) teeth per side, apex usually symmetric and spinescent, spine 0.3-2 mm. Pollen cone fascicles terminal, 1-3(-5) together, broadly obovoid, each of 8-20 cones, occasionally a few also around base of seed cone; peduncle 2-4 mm; cones narrowly oblong-conical. Seed cones terminal, 1-4 together, at pollination shortly cylindric-ovoid, ca. 12 × 8 mm, later becoming ovoid or subglobose, 1.8-4.5 × 1.2-4 cm; bracts glaucous or rather glossy, broadly ovate or triangular-ovate, base with short claw 1/5-1/2 × total length of bract, distal part gradually narrowed toward pointed apex, 1/14-1/5 × total length of bract. Seeds dark brown, oblong or narrowly ovate, 5-6 × ca. 4 mm, narrowly winged laterally. Pollination Jan-May, seed maturity Aug-Nov.
A very variable species: specimens occur with spinescent or obtuse leaf apices and with or without white stomatal bands on the adaxial leaf surface. The latter character is at least partly
dependent on the age of the tree and the position of the leaf on the tree: leaves exposed to sunlight have less conspicuous adaxial stomatal bands than those in shade, as do leaves of
old trees. Variants also occur with strongly glaucous leaves.
The most important fast-growing timber tree of the warm regions S of the Chang Jiang valley; it is propagated by seed, cuttings, or suckers. The wood is strongly resistant to rot, is not eaten by termites, and is easily worked; it is used in constructing buildings, bridges, ships, and lamp posts, in furniture manufacture, and for wood fiber.
Mixed broad-leaved forests or forming small, pure stands, rocky hillsides, roadsides; 200-2800 m. Exact native distribution uncertain owing to widespread planting: Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Sichuan, C and N Taiwan, Yunnan, Zhejiang [?Cambodia, Laos, N Vietnam]