| # The grass genera of the world |

L. Watson, T.D. Macfarlane, and M.J. Dallwitz

### Bambusa Schreber

Latinised from Malay vernacular bambu.

Type species: Type: Bambos arundinaceae Retz.

Including Arundarbor Kuntze, Criciuma Soderstrom & Londoño, Dendrocalamopsis (Chia & Fung) Keng f., Eremocaulon Soderstrom & Londoño, Ischurochloa Büse, Leleba Nakai, Lingnania McClure, Neosinocalamus and Tetragonocalamus Nakai

Excluding Guadua Kunth,, Holttumochloa K.M. Wong, Kinabaluchloa K.M. Wong, Maclurochloa K.M. Wong, Soejatmia K.M. Wong,

Habit, vegetative morphology. Perennial. The flowering culms leafless, or leafy. Culms (200–)500–3500 cm high; woody and persistent; to (0.5–)4–12(–17) cm in diameter; scandent, or not scandent; branched above. Buds from which the primary culm branches arise (where recorded) 1. Primary branches (1–)3–10, or 11–20 (where recorded (rarely ... ) derived from a single bud, usually with one branch becoming dominant); sometimes clumped. The branching (exclusively?) dendroid. Culm nodes glabrous. Culm leaf sheaths present; deciduous (rarely), or persistent; leaving a persisten girdle (sometimes), or not leaving a persistent girdle; conspicuously auriculate (nearly always), or not conspicuously auriculate. Culm leaves with conspicuous blades. Culm leaf blades linear, or lanceolate, or ovate, or triangular (commonly). Culm internodes hollow (sometimes nearly solid). Pluricaespitose. Rhizomes pachymorph. Plants unarmed (? - with Guadua excluded). Leaves not basally aggregated; auriculate, or non-auriculate (rarely?); with auricular setae, or without auricular setae. Leaf blades broad, or narrow (small to moderate-sized); pseudopetiolate; cross veined, or without cross venation; disarticulating from the sheaths, or persistent (but at least demarcated); rolled in bud. Ligule an unfringed membrane to a fringed membrane; short or long. Contra-ligule present (usually), or absent.

Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets. Not viviparous.

Inflorescence. Inflorescence indeterminate; with pseudospikelets; of pseudospikelets, these solitary or in tufts, fascicles or capitula on leafless branches; open; spatheate (with or without foliage leaves); a complex of ‘partial inflorescences’ and intervening foliar organs. Spikelet-bearing axes very much reduced, or paniculate to capitate; persistent. Spikelets not secund.

Female-fertile spikelets. Spikelets unconventional; 10–80 mm long; oblong, or ovate, or lanceolate, or linear; compressed laterally to not noticeably compressed; when empty glumes present, disarticulating above the glumes; disarticulating between the florets; commonly with distinctly elongated rachilla internodes between the florets. Rachilla prolonged beyond the uppermost female-fertile floret; hairless. Hairy callus absent.

Glumes (i.e. transitional, empty glumes, which are additional to bud-bearing basal bracts) present (usually), or absent (rarely); one per spikelet to two ((0-)1–2); very unequal, or more or less equal; shorter than the spikelets; shorter than the adjacent lemmas; hairless; not pointed; awnless; carinate; similar. Lower glume longer than half length of lowest lemma; 7–18 nerved. Upper glume 7–18 nerved. Spikelets with incomplete florets. The incomplete florets distal to the female-fertile florets, or both distal and proximal to the female-fertile florets. The distal incomplete florets merely underdeveloped. The proximal incomplete florets 0–3 (? - fewer than 4); sterile. The proximal lemmas awnless; several-nerved; exceeded by the female-fertile lemmas; similar in texture to the female-fertile lemmas.

Female-fertile florets (1–)2–20 (-‘many’). Lemmas similar in texture to the glumes; not becoming indurated; entire; blunt; awnless (usually); hairless; carinate to non-carinate; 9–22 nerved. Palea present; relatively long to conspicuous but relatively short; not convolute; entire to apically notched (the apex rounded, truncate or only slightly cleft); awnless, without apical setae; not indurated; several nerved (about 6–16); 2-keeled. Palea keels wingless (with Guadua excluded). Lodicules present; 3; free; membranous; ciliate; not toothed; heavily vascularized. Stamens 6; with free filaments (nearly always), or monadelphous (rarely). Anthers 3.5–8 mm long; penicillate, or not penicillate; with the connective apically prolonged, or without an apically prolonged connective. Ovary apically hairy; with a conspicuous apical appendage (commonly), or without a conspicuous apical appendage. The appendage broadly conical, fleshy. Styles fused. Stigmas 3 (usually?).

Fruit, embryo and seedling. Fruit free from both lemma and palea; longitudinally grooved; not noticeably compressed; with hairs confined to a terminal tuft. Hilum long-linear. Pericarp thin. Embryo small; not waisted. Endosperm containing compound starch grains. Embryo with an epiblast.

First seedling leaf without a lamina.

Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae present. Intercostal papillae over-arching the stomata; several per cell. Long-cells similar in shape costally and intercostally; differing markedly in wall thickness costally and intercostally. Mid-intercostal long-cells rectangular; having markedly sinuous walls. Microhairs present; panicoid-type; 36–48 microns long (in B. arnhemica); 6–9 microns wide at the septum. Microhair total length/width at septum 4.5–8 (i.e. very variable, in B. arnhemica). Microhair apical cells 15–21 microns long. Microhair apical cell/total length ratio 0.37–0.46. Stomata common; 21–27 microns long. Subsidiaries parallel-sided, or dome-shaped, or triangular; including both triangular and parallel-sided forms on the same leaf. Intercostal short-cells common; in cork/silica-cell pairs. Costal short-cells conspicuously in long rows. Costal silica bodies saddle shaped, or oryzoid.

Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll with non-radiate chlorenchyma; with arm cells; with fusoids. Leaf blade adaxially flat. Midrib conspicuous; having complex vascularization. The lamina distinctly asymmetrical on either side of the midrib. Bulliforms present in discrete, regular adaxial groups; in simple fans. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming ‘figures’.

Culm anatomy. Culm internode bundles in three or more rings.

Phytochemistry. Leaves without flavonoid sulphates (1 species).

Cytology. Chromosome base number, x = 12. 2n = 24, 48, 70, and 72. 4 and 6 ploid (rarely diploid). Chromosomes ‘small’.

Classification. Watson & Dallwitz (1994): Bambusoideae; Bambusodae; Bambuseae. Soreng et al. (2015): Bambusoideae; Bambusodae; Bambuseae; Bambusinae, or Guaduinae (Criciuma, Eremocaulon). About 120 species.

Distribution, phytogeography, ecology. Tropical and subtropical Asia, Africa, America.

Commonly adventive.

Economic aspects. B. arundinacea, B. dissemulator, B. duriuscula, B. gibba, B. lapidea, B. malingensis, B. sinospinosa, B. tuldoides, B. vulgaris etc. are widely used for general constructional work; others (e.g. B. pervariabilis) for fishing rods, ski poles, umbrella shafts, furniture etc.; others (e.g. B. chungii) for weaving; others (e.g. B. flexuosa, B. gibba, B. sinospinosa) are useful barrier plants; and the shoots of many (e.g. B. beecheyana, B. gibboides, B. vulgaris) are edible. Pulp for paper and rayon is obtained from (e.g.) B. guadua.

Hybrids. Claimed intergeneric hybrids with Saccharum are erroneous, representing apomixis.

Rusts and smuts. Rusts — Dasturella, Stereostratum, and Puccinia. Taxonomically wide-ranging species: Dasturella divina and Stereostratum corticoides. Smuts from Tilletiaceae. Tilletiaceae — Tilletia.

References, etc. Leaf anatomical: Metcalfe 1960; studied by us - B. arnhemica F. Muell.

Special comments. This treatment follows Clayton and Renvoize (1986). Soderstrom and Ellis (1987) refer Criciuma, Eremocaulon and Guadua to their subtribe Guaduinae, along with Olmeca, and place Tetragonocalamus in the Arundinariinae, but revised generic descriptions adequate for the present purpose are not available. Further problematic ‘genera’ are Kinabaluchloa K.M. Wong (including B. wrayi), Holttumochloa K.M. Wong (including B. magica), Maclurochloa K.M. Wong (= B. pauciflora and B. montana), and Soejatmia K.M. Wong (= B. ridleyi). Sound generic circumscriptions depend on adequate comparative descriptions, and will be extensively unachievable for bamboos until the descriptive terminology of inflorescence and spikelet morphology has been standardized, and encoded with reference to material at world level.

Illustrations. • Bambusa vulgaris, as B. thouarsii: Kunth (1835). • Bambusa oldhamii: Hook. Ic. Pl. 28 (1903). • Bambusa teres and B. polymorpha: Camus (1913). • Abbreviations for Camus (1913) figures. • Bambusa pallida and B. affinis: Camus (1913). • Bambusa kharsiana and B. balcooa: Camus (1913). • Bambusa vulgaris (as B. striata): Bot. Mag. 100 (1874). • Pseudospikelets (Bambusa arnhemica). • Bambusa atra, abaxial epidermis of leaf blade: this project.

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, and classifications. See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., Macfarlane, T.D., and Dallwitz, M.J. 1992 onwards. The grass genera of the world: descriptions, illustrations, identification, and information retrieval; including synonyms, morphology, anatomy, physiology, phytochemistry, cytology, classification, pathogens, world and local distribution, and references. Version: 15th June 2025. delta-intkey.com’.

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