Plants scrambling, spreading through tree branches; rhizomes pachymorph, short-necked. Culms to 10 m, 0.5–1.5 cm in diam., initially erect, then pendulous; nodes lightly raised with a hard thin flange below a short girdle, no supra-nodal ridge; internodes terete, smooth, not grooved, to 50 cm long, dark green, with very thin persistent wax that becomes flaky, thick-walled to nearly completely solid. Branches initially 7-40, central dominant and approaching size of culm, others much smaller and subequal, verticillate, nodes with tall girdle, thickened and asymmetric on geniculate nodes, basal internodes compressed, secondary branches developing tardily, all branches subtended by a sheath; buds initially closed at front, prophyll tall, 2-keeled. Culm sheaths extremely tough, narrowly triangular, very persistent until branch development, brown-spotted, basally and marginally more or less scabrous with microscopic retrorse points, points denser on distal sheaths, margins membranous and not ciliate; ligule inconspicuous, blade tiny, needle-like, erect, persistent. Leaf sheaths narrow, glabrous, persistent; blade very thin, linear-lanceolate, apex long-acuminate, 8-12(-15)cm in length, lightly rugose, venation not tessellate. Synflorescence semelauctant, racemose panicles, bracteate, lateral spikelets subtended by a bract and basally prophyllate. Prophyll and glumes not subtending buds. Spikelets sessile to shortly pedicellate, several flowered, followed by a terminal incomplete floret. Rachilla disarticulating and florets separately deciduous. Glumes 1, or absent in terminal spikelets; lemma glabrous. Palea 2-keeled, usually equal in length to lemma. Lodicules 3. Stamens 6; filaments free. Ovary oblong or ovate, upper portion pubescent or glabrous; style 1; stigmas 3. Caryopsis shortly terete, grooved. Name from Neo (Greek, new), and Micro + calamus (Greek, small + reed), acknowledging Microcalamus Gamble, which was invalid as the name had been used previously for a different genus. Gamble did not republished the genus with a valid name because he was persuaded by Kew grass taxonomists that it should remain in Arundinaria, despite having 6 stamens.
Neomicrocalamus is a small genus of approximately 2-4 subtropical scandent species, native to the E Himalayas, NE India and Yunnan, related to Dendrocalamus and Bambusa, readily distinguished from all other genera by the extremely tough culm sheaths with needle-like blades. Collections from the Zullah Valley in the Khasia Hills were described by James Rollo as ‘a creeping bamboo’. Young seedlings were first encountered in Bhutan, and were thus expected to develop long rhizome necks, but stayed in tight clumps with short-necked pachymorph rhizomes instead.
Although morphologically somewhat similar to the more tropical Racemobambos, DNA analysis has shown that it is not closely related.
Delightful bamboos forming curtain-like cascades of very attractive foliage, without the messy sheaths seen in Chusquea species of similar habit, leaves slightly crinkled, glossy, very smooth, paper-thin and rustling. Very resistant to pests and potentially well-suited to indoor cultivation, but now very rare in western horticulture, and included here only because Himalayacalamus planatus was previously misidentified and cultivated under the name Neomicrocalamus microphyllus, and plants under that name have also sometimes been purchased directly from China. To complicate matters further, however, the validly published name N. microphyllus is a synonym of Ampelocalamus microphyllus, and the plants that were described under an invalid name as N. microphyllus are actually N. prainii.
Used for weaving, especially the hats and brightly coloured ornamental basketry of Bhutan.