4. Schizachyrium fragile (R. Brown) A. Camus, Ann. Soc. Linn. Lyon, N.S. 70: 87. 1924.
斜须裂稃草 xie xu lie fu cao
Andropogon fragilis R. Brown, Prodr. 202. 1810; A. brevifolius Swartz var. fragilis (R. Brown) Hackel; A. fragilis var. sinensis Rendle; A. obliquiberbis Hackel; Schizachyrium fragile var. sinense (Rendle) Jansen; S. obliquiberbe (Hackel) A. Camus; Eulalia simplex Hosokawa.
Annual. Culms tufted, wiry, erect or geniculate, 15–60 cm tall, sparingly branched, glabrous. Leaves mainly basal; leaf sheaths lightly keeled, glabrous or a few hairs at mouth; leaf blades linear, usually folded, 4–8 × 0.1–0.2 cm, glabrous, apex acute or subacute; ligule 0.2–0.5 mm. Raceme 4–8 cm, enclosed at base by spatheole; rachis internodes and pedicels columnar, broadened distally, slightly shorter than sessile spikelet, a dense band of white ca. 3 mm hairs from lower part of one margin slanting obliquely across upper part of internode, then transversely across apex to top of other margin, pedicel often similarly obliquely bearded. Sessile spikelet 6–7 mm; lower glume linear-lanceolate, 2-keeled throughout, subleathery and white-villous below middle, membranous and glabrous above, keels winged for most of length but broadest on membranous part, apex narrow, keels minutely extended; upper lemma 2-lobed to near base; awn 1–1.5 cm. Pedicelled spikelet reduced to 1 or 2 glumes, 1.5–3.5 mm, ciliate on both margins, lower glume with ca. 3 mm awn. Fl. and fr. Aug–Dec.
Hillsides; below 1000 m. S Anhui, Fujian, Guangdong, Guangxi, Hunan, Jiangxi, Taiwan [Indonesia; Australia, Pacific Islands].
This species is similar to Schizachyrium exile (Hochstetter) Pilger, from India and Africa, which is another slender annual with reddish racemes and conspicuous, contrasting, white hairs. However, S. exile has rachis internodes villous on the back and glabrous near the apex, and the lower glume of the sessile spikelet is wingless. The dense beard curling across the rachis internode from one side to the other in S. fragile is curious and quite distinctive.