A graceful bamboo, with single culms arising at intervals from a long, creeping, scaly rhizome. Stems 10 to 15 ft or more high, about 1⁄2 in. in diameter; purplish at first, changing to brownish green; from 3 to 7 in. between the joints; branches purple, slender, forming dense clusters on the older stems. Stem-sheaths mottled within, hairy on the margin, truncate at the apex, with a narrow, falcate, bristly auricle on each side of the short, subulate blade. Leaf-sheath fringed with bristles and short hairs where it joins the base of the blade. Blades 11⁄2 to 4 in. long, 1⁄4 to 1⁄2 in. wide, brilliant green above, slightly glaucous beneath, edged with minute bristles on each margin. There are two or three secondary veins on each side of the midrib, and the tessellation is very minute, but quite distinct under a lens.
Native of the N.W. Himalaya; introduced by Col. Edmund Smyth from Garhwal, about 1865, and first cultivated at Elkington Hall, Lincolnshire. It is a handsome and graceful bamboo, spreading rapidly by means of underground rhizomes, sometimes becoming a nuisance when running under lawns or invading other plants. It is very hardy, and although it loses its leaves in severe winters its stems are rarely injured. It grows at elevations of 10,000 to 11,000 ft, and is said to flower and seed in its native home at intervals of twenty to twenty-five years, when vast fields of it die. A few plants flowered in the British Isles in 1910 and 1911, and in 1920; since 1957 flowering has been reported in various gardens, complete plants or isolated stems coming into bloom. These may be the forerunners of a general flowering, although the plants at Kew in 1967 showed no signs of flowering.
From the Supplement (Vol. V)
A. jaunsarensis Gamble, given as a synonym, is in fact the correct name for this species.