高山松 gao shan song

Pinus prominens Masters; P. sinensis D. Don var. densata (Masters) Shaw; P. tabuliformis Carriere var. densata (Masters) Rehder; P. wilsonii Shaw (1911), not Roezl (1857).

Trees to 30 m tall; trunk to 1.3 m d.b.h.; bark reddish brown, scaly and plated when young, finally dark grayish brown, forming irregular, square, thick plates; crown ovoid-conical, broadly ovoid in old trees; branches spreading; 1st-year branchlets shiny yellowish brown, stout; 2nd- and 3rd-year branchlets reddish brown; winter buds dull brown, ovoid-conical, ca. 15 × 6 mm, slightly resinous, scales white fringed at margin, acuminate at apex. Needles persisting for 3 years, usually 2(or 3) per bundle, straight, slightly twisted, 8-14 cm × 1-1.5 mm, stomatal lines present on all surfaces, resin canals 3 or 4, marginal, occasionally 1 or 2 median, base with persistent sheath initially 5-10 mm, margin finely serrulate, apex acute. Pollen cones yellowish brown, cylindric, 10-18 × 3-4.5 mm. Seed cones solitary or in pairs, pendulous, sessile or very shortly pedunculate, shiny chocolate brown at maturity, narrowly ovoid before opening, ovoid or broadly ovoid when open, 4-6 × 4-7 cm, persistent. Seed scales with apophyses prominent, rhombic, 4-7 mm thick, sharply transversely keeled; umbo dorsal, with a short prickle. Seeds light grayish brown, ellipsoid-ovoid, 4-6 mm; wing 1.5-2 cm. Pollination May, seed maturity Oct of 2nd year.

* Open forests in high mountains, forming pure stands or (below 3000 m) mixed with Pinus armandii and P. yunnanensis; 2600-3500 (-4200) m. S Qinghai, W Sichuan, SE Xizang, Yunnan

Morphologically intermediate between Pinus yunnanensis of lower elevations and P. tabuliformis of more northerly latitudes. Molecular evidence supports the hypothesis that P. densata originated as a Tertiary natural hybrid involving the former two species and a third, unknown species.

Can be used for afforestation in the alpine zones of W Sichuan and E Xizang.