Chimonobambusa quadrangularis

Synonyms: Bambusa quadrangularis Franceschi; Arundinaria quadrangularis (Franceschi) Makino; Tetragonocalamus quadrangularis sensu Nakai.

Thai names: ไผ่สี่เหลี่ยม (phai si liam); ไผ่เหลี่ยม (phai liam). — BKF [#1368].

English name: Square Bamboo.

Distribution: THAILAND: introduced, in cultivation, rare. No records are known about naturalized populations in Thailand. — CHINA (South): The species originates from southern mainland China and is distributed in Anhui, Fujian, Guangxi, Hunan, Jiangsu, Jiangxi, Zhejiang, and Taiwan. — Nowadays widespread in tropical and subtropical regions worldwide, both naturalized and cultivated. — N. Bystriakova & al., Bamboo Biodiversity, 2003: map 20 [#1342].

Local distribution: Rarely offered for sale in Chiang Mai.

Culm size: Height 3–8 m, diameter 1–4 cm.

Descriptions:

(1) "Culms erect, 3–8 m tall, to 2.5 cm in diam.; internodes obtusely 4-angled, 8–22 cm, sparsely coarsely scabrid, apically more densely so; nodes prominent, supra-nodal ridge raised at branching nodes, level at branchless nodes, lower nodes each with a ring of short, declined root thorns; sheath scar corky, initially with a fulvous, tomentose, minutely setose ring. Culm sheaths deciduous, shorter than internodes, papery, veins prominent, transverse veinlets purple-brown, margins ciliate; auricles, oral setae, and ligule absent; blade deciduous, subulate, 3–5 mm, articulate. Leaves 2–5 per ultimate branch; sheaths leathery, glabrous, margins apically ciliate; oral setae deciduous, erect, glabrate; ligule truncate, short, ciliate, with minute setae; pseudopetiole ca. 1.8 mm; blade elliptical to lanceolate, 8–29 × 1–2.7 cm, papery, abaxially initially pubescent, adaxially glabrous, secondary veins 4–7-paired, tertiary veins 5–7, apex acuminate. … [flowers described, seeds unknown]". — Flora of China, accessed 8 July 2020 [#1303].

(2) T. H. Wen, J. Amer. Bamboo Soc. 11 (1-2), 1994: p. 40 [#1176].

(3) Kew GrassBase [#1335].

(4) Flora of Taiwan [#1106].

Images: Line drawing in Flora of China [#1303]; Flora of Taiwan [#1106]. Photos in AsianFlora (culms, habit) [#1332].

Comments: Flowering cycle 100+ years [#1320].