不丹松 bu dan song

Trees to 25 m or more; crown moderately open, not twiggy; branches spreading, drooping, sinuous; 1st-year branchlets conspicuously whitish bloomed, glandular pubescent; 2nd-year branchlets with thin, pale gray-green bark. Needles shed in 2nd year, 5 per bundle, pendulous, very slender, curved, triangular in cross section, 15-24 cm, adaxial surface grass green with no stomata, 2 abaxial surfaces conspicuously whitish bloomed, each with 4-7 stomatal lines, resin canals 3(or 4), adaxial 2 marginal or submarginal, abaxial 1(or 2) marginal or submarginal and always asymmetrically placed. Seed cones pedunculate (peduncle (1-) 4.5-6 cm), elongate-cylindric, 12-20 × 3-4 cm (5-7 cm wide when open). Seed scales rather elongate, thinly woody, base cuneate; apophyses rhombic, 1-1.5 × 1.5-2.5 cm, keeled, apex subacute. Seeds brown, obovoid, compressed, 6-8 × 4-5 mm; wing persistent, ca. 2 × 0.7-1 cm.

SE Xizang [Bhutan]