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Plants shrub-like to subarboreous, usually densely clumping; rhizomes pachymorph, necks similar in length, up to 30 cm. Culms in a single dense to loose clump (unicespitose), to 7 m tall and 3.5 cm in diam., erect or curving at base, apically nodding to pendulous; internodes to 50 cm, terete, usually finely ridged, without fine purple spots, usually blue-grey with light persistent wax, becoming glossy; nodes scarcely to moderately raised. Branches 5--7(--14) per mid-culm node at first, above promontory, subequal, initially erect, becoming deflexed, lateral branch axes lacking subtending sheaths; buds at mid-culm lanceolate, with 2 often very tall, single-keeled bracts, open at front (closed at culm base), 3--9 initials visible within. Culm sheaths usually long-triangular, papery and deciduous (rarely oblong, thickened and persistent); blades long, reflexed, deciduous. Leaf sheaths usually persistent; blade usually matt, thin, venation distinctly tessellate, either persistent or deciduous in winter. Synflorescence ebracteate, semelauctant; branching paniculate, erect, never unilateral, usually long-exserted from narrow subtending sheath, often fasciculate in dense panicles. Spikelets several-flowered; glumes basally loose, and frequently subtending reduced non-viable buds. Stamens 3. Stigmas 3. Named after Norman L. Bor, forester and grass taxonomist of the Indian Forest Service and the Royal Botanic Gardens Kew.
Borinda is a temperate to subtropical genus that currently contains 21 species, native to the Sino-Himalayan mountains from C Nepal, S Tibet and S Vietnam to E Yunnan and W Sichuan. It includes a large number of species with high horticultural potential, many of which are indigenous to dwindling forest areas or individual mountain tops, and are thus potentially threatened with extinction. Most were described initially in Fargesia, and many further species in that genus are likely to require transferral once their flowers become known. Most of the species have been described relatively recently, and the identification of a large number of new Borinda introductions remains problematic and may not be possible without collaborative botanical fieldwork.
Although leaf blades of many bamboos can be lost under extreme conditions, the routinely deciduous leaf blades of several Borinda species in winter are unusual in the woody bamboos. Associated with thickened sheaths and high altitude habitats, this would appear to be an adaptation to cold and low water availability in winter.
Difficult to distinguish from Fargesia without flowering material, although leaves are thinner and a fresher green and culms are usually finely ridged, with either longer and more triangular culm sheaths or thickened persistent culm sheaths in the species with deciduous leaf blades. Similar to Yushania but with shorter more consistent rhizomes, thus clump-forming not running, and leaf blades arranged in a more regular fashion. This genus contains many species of high economic value in their native countries and of great horticultural potential elsewhere.
Stapleton, C.M.A. (1998). New combinations in Borinda (Gramineae–Bambusoideae). Kew Bull. 53: 453–459.
Stapleton, C.M.A. (2000). New half-hardy bamboos from the Sino-Himalayan region. Amer. Bamboo Soc. Newsl. 21 (4): 16–21, with Bor biography
Stapleton, C.M.A. (2006). New taxa and combinations in cultivated bamboos (Poaceae: Bambusoideae). Sida 22(1): 331–332.
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