Chimonobambusa quadrangularis (Franceschi) Makino
by W.R. Sykes
square-stemmed bamboo
Diffuse bamboo with extensively running rhizomes. Culm 3-6 m, dark green; nodes swollen and prominent; internodes obtusely quadrangular in cross section; lower internodes less obviously so; lowest nodes with short indurated adventitious rootlets which become spiny. Culm-sheath to 12 × 8 cm, triangular, tardily deciduous, purple with dark purplish tessellations; auricles and oral bristles 0; sheath-blades very small. Branches spreading widely and ± drooping above, sometimes purplish. Leaf-sheath with long bristles at apex. Leaf-blade 9-24 × 0.7-2 cm, narrow lanceolate or linear-lanceolate, deep green on both surfaces, tessellate, ± drooping.
N.: Wanganui District (Aird property near Fordell). Plantation of introduced, mainly deciduous trees in small valley where it has spread for some distance from the original planting.
Naturalised from China.
Occasionally cultivated in N.Z. Chimonobambusa quadrangularis is very easily distinguished in N.Z. from any other bamboo by its quadrangular stems and the spiny lowermost culm nodes.
Also known in N.Z. as Phyllostachys quadrangularis (Franceschi) Rendle and Tetragonocalamus angulatus (Munro) Nakai.
The type sp., C. marmorea (Mitford) Makino, marble bamboo, is sometimes cultivated, but although it has running rhizomes it has not yet been reported as growing wild. C. marmorea has pencil-thick culms only c. 1 m high and culm-sheaths attractively marbled brown and white. Neither C. marmorea nor C. quadrangularis is known to have flowered in N.Z.
