4. Pinus yunnanensis Franchet, J. Bot. (Morot). 13: 253. 1899.
云南松 yun nan song
Trees or rarely shrubs; bark brown-gray, longitudinally fissured, scaly; branchlets reddish brown, thick, glabrous; winter buds red-brown, ovoid, large, not resinous. Needles (2 or)3 per bundle, flabellate-triangular or semiorbicular in cross section, 7-30 cm × 1-1.2 mm, stomatal lines present on all surfaces, resin canals 4 or 5, median and marginal, base with persistent sheath. Seed cones shortly pedunculate, green, maturing to brown or chestnut brown, conical-ovoid, 5-11 cm, dehiscent or indehiscent at maturity. Seed scales oblong-ellipsoid, ca. 3 × 1.5 cm; apophyses usually swollen, cross keeled, rarely recurved; umbo slightly sunken or slightly protruded, ending in a minute prickle. Seeds brown, slightly appressed, nearly ovoid or obovoid, 4-5 mm; wing 1.2-1.4 cm. Pollination Apr-May, seed maturity Oct.
* Mountains, river basins, dry and sunny slopes; 400-3100 m. Guangxi, Guizhou, SW Sichuan, SE Xizang, Yunnan
The timber is used for construction, railway sleepers, boards, furniture, and wood pulp. The trunk can be used as a source of resin, the roots for cultivating fungi, and the bark for
producing tannin.
