| Plant height | | 1–2 m | 0.1–2.0 (–3) m | 1.5–3 m | 1–2.5 m | 0.3–0.8 m |
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| Rhizome | | up to 1.5 m long, smooth, glabrous | short, scaly | scaly | scaly, whitish pubescent | short, scaly |
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| Culm nodes | | glabrous and smooth | appressed silky pubescent | swollen, densely bearded or appressed silky-pilose glabrescent | glabrous and smooth |
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| Leaf sheath | | abaxially pilose with tubercle-based hairs, adaxially glabrous, densely ciliate along one margin only with tubercle-based hairs | smooth and glabrous, striate, or sparsely to densely covered with tubercle-based hairs, margins short ciliate, rarely both margins eciliate | hispid with tubercle-based hairs at young or glabrous, margin densely short ciliate with tubercle-based hairs | glabrous to pilose on the back, margins densely hairy | smooth and glabrous or pilose, densely ciliate along one margin |
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| Ligule height | | (0.2–)0.3–0.5 mm | 0.3–1 mm | 0.3–1.5 mm | 0.5–1 mm | ca. 0.5 mm |
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| Leaf blade | Size | 10–50 × 0.4–1.4 cm | 2–50 × 0.2–1.8 cm | 30–80 × 1–2.5 cm | 13–70 × 0.3–1.6 cm | 11–20 × 0.2–0.5 cm |
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| Surface | hispid on both surfaces with tubercle-based hairs | glabrous or thinly to densely pilose with tubercle-based hairs | tuberculate-hispid with tubercle-based hairs or glabrescent | hispid on both surfaces with tubercle-based hairs | glabrous or pilose or upper surface with short hairs just above ligule, smooth and somewhat scabrid on lower surface |
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| Margin | scaberulous | - | scabrous | - | scabrid or often denely ciliate |
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| Panicle | Appearance | open or loosely contracted | open or loosely contracted | narrowly oblong dense | narrowly cylindrical, loosely contracted, dense narrowly elliptic in outline |
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| Size | 40–65 cm long | 10–50 cm long | 30–65 cm long | 9.5–42 cm long | 10–17 cm long |
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| Axil of rachis | | villous | - | - | usually villous | densely and finely ciliate |
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| Central axis | | smooth, scabrid towards apex, strongly striate (striations wavy), glabrous | scaberulous or almost smooth | scaberulous | scabrid, striate, sparsely pubescent | scabrid-hispidulous |
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| Panicle branches Size | 2–20 cm | 7–20 cm | 5–25 cm | 1.8–10 (–11.5) cm | 3-6 cm |
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| Arrangement | alternate, opposite, subopposite or whorled, erect | alternate or pseudo-whorled or subverticillate or fascicled | crowded in whorls or usually crowded in alternate, suberect whorls | Irregular or sub-whorled |
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| Branching pattern | lower branches with several branchlets, upper ones mostly simple | simple or lowest branched | - | usually simple or occasionally with secondary branches | - |
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| Arrangement of spikelets | loosely spiculate | loosely to densely spiculate | densely spiculate, concealing the stout main axis | densely spiculate, spike-like | loosely spiculate |
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| Spikelet | | 4–5 mm long | 3–5.5 mm long | 3–5 mm long | 2.5–3.7 mm long | 3.8–4.5 mm long |
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| Pedicel | Size | 1.2–8 mm long, | shorter or equal to spikelets | 0.5–5 mm long, | 0.3–2.2 mm long | shorter than the spikelets |
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| Surface | scaberulous | - | scaberulous | scabrous or hispid | hairy or scabrid |
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| Lower glume | Size | 2.8–4 × 0.9–1.5 mm | 3–3.5 mm long | 3–4 mm long | 1.9–3.1 mm long | 2.5–3 mm long |
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| Vein features | (4–)5–7-veined, midvein keeled, scabrid towards apex, rarely scabrid throughout | strongly 3-veined, veins scabrid | 3–5-veined, scabrid on veins | 3–5-veined, scabrous 3–5-veined on veins |
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| Upper glume | Size | (3.8–)4.2–5 × 1–1.5 mm 3.5–5.5 × 1.5–2 mm | 4–5 × 1–1.2 mm | - | as long as spikelet |
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| Vein features | 5–7-veined, usually glabrous, sometimes veins with few hispid hairs and margins sparsely hairy | faintly 5-veined | 3–5-veined, glabrous or scaberulous on veins | 5-veined, glabrous | 5-veined, scabrid on veins |
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| Lower floret | Nature | always bisexual | staminate or barren | staminate | staminate or barren | staminate |
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| Size | longer than lower glume | equaling or longer than lower glume | slightly longer than lower glume | - | as long as lower glume |
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| Lower lemma | Size | 3–4 × 1–1.6 mm | 2.5−3.5 mm long | 3−3.5 mm long, | 1.9−2.9 mm long | - |
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| Vein features | (5–)7-veined, only the midvein somewhat keeled at apex | 3–5-veined | 3−5-veined | 3−5-veined | 5-veined |
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| Surface | glabrous, rarely sparsely hairy at margin, smooth | glabrous, smooth | - | - | - |
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| Upper lemma | Size | 2–2.2 mm long | 1–2 mm long, | 2−2.5 mm long | 1.6−2.3 mm long | 2–3 mm long |
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| Apex | usually retuse (- emarginate), sometimes one lobe attached to awn, often obtuse (then awn terminal), fimbriolate | bifid | minutely bifid | apex narrowed into a subentire or very poorly developed minutely lobed awn or awnless |
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| Surface | glabrous | pubescent below | - | - | - |
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| Upper palea | Size | 2.3–2.4 × 0.5–0.6 mm | 1−2.5 mm long | 2−2.5 mm long | 1.6−2.1 mm long | shorter and narrower |
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| Apex | acute with few cilia | minutely bifid | dentate, minutely bifid | acute | - |
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| Margin | margin auriculate (door-like flaps); auricle obliquely obovate-spathulate, strongly overlapping | margin with door-like flaps | - | - | - |
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| Surface | chartaceous, granulate dorsally | subcoriaceous, granulate dorsally | - | - | minutely scabrid |
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| Awn | Size | (2–)4–5 mm long | 3.5–6 mm long | 4–5 mm long | up to 2 mm long | 2.7–6 mm long |
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| Nature | persistent | persistent | persistent | soon deciduous | - |
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| Callus hairs | | 1/4–1/2 length of lemma | 1/4–1/3 length of lemma | ca. 1/4 length of lemma | 1/10–1/5 length of lemma | ca. 1/2 length of lemma. |
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| Anthers | | 1–2 × 0.2–0.5 mm long | 0.8−1.5 mm long | 1–1.8 mm long | 0.7–1.1 mm long | ca. 1 mm long |
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