Thamnocalamus crassinodus (T.P. Yi) Demoly Bambou 21: 15 (1995).

 Synonyms: Fargesia crassinoda T.P. Yi, J. Bamboo Res. 2(2): 24. 1983; Sinarundinaria langtangensis R. Manandhar & D.M. Bajracharya; Thamnocalamus spathiflorus var. crassinodus (T.P. Yi) Stapleton, Edinburgh J. Bot. 51: 284. 1994; Thamnocalamus unispiculatus T.P. Yi & J.P. Shi

Plants forming dense clumps. Rhizomes pachymorph, neck 2--5 cm long. Culms  to 3 m, to 1.5 cm in diam., pendulous; internodes to 15 cm, terete, lightly to densely blue-grey waxy at first, becoming yellow green, smooth, glabrous, wall thick; nodes irregularly swollen, supra-nodal ridge prominent, sheath scar thin; branches initially (3)-5-(7), strong. Culm sheaths deciduous, much shorter than internodes, triangular, tough, smooth, light purple green, densely red or light brown setose to glabrous, apex narrow, margins distally densely c. 3mm red or golden ciliate; auricles absent or very small; oral setae several, erect, 4-8mm, clumped; ligule to 3 mm, fimbriate to 3 mm, tomentose; blade triangular, lightly pubescent, usually erect, reflexed towards base of culm, very persistent, margins ciliate. Leaves 4--10 per ultimate branch; sheath distally lightly tomentose, external margin ciliate; auricles absent or very small; oral setae absent or very few and weak, rarely several and strong, erect or curved, ca. 1-3 mm; ligule convex, to 1 mm, tomentose, ciliate to 1 mm; external ligule white-ciliate to 2 mm; blade lanceolate to narrowly lanceolate, to 10 × 1.0 cm, base rounded, glabrous, secondary veins 3-4-paired, margins distally spinescent, transverse veins distinct. Synflorescence unknown. Name crassinodus Latin, ‘thick node’.

This variable group of plants is found around the geographic overlap of T. nepalensis and T. spathiflorus in C Nepal and adjacent valleys of Kyirong & Nyalam Counties in Tibet, and can show some of the characters of both of those species, particularly in terms of culm sheath hairs, suggesting a hybrid origin. They can often be distinguished by a thickening of the culm in the region of the nodes, and by the leaf blades, which are often smaller, narrower and more numerous than those of T. spathiflorus or T. nepalensis. Culms may have a dense blue-grey wax on the internodes at first. A cultivar from near Gosainkund is illustrated here, along with similar but hairy culm sheaths from a different clone (from Pitt White).

 First introduced into the UK as seedlings from Langtang Valley and below the Gosainkund ridge in C Nepal in 1971 and 1973, by Merlyn Edwards. Various more recent introductions have also been made.