生活型

herb

形態特徵

• Annual or probably a short-lived perennial under certain conditions. Culms solitary or few together, erect, 30-100 cm tall, triquetrous, smooth, with a bulbose enlargement at base.
• Leaves several, shorter than culm; blades linear, 4-10 mm wide, flattish, herbaceous; sheaths rather long, brownish or purplish brown.
• Corymbs ample, compound to decompound, loose to subdense, 5-30 cm wide; rays 5-12, patent, longer ones to 20 cm long; raylets several to each secondary corymb, 0-3 cm long; spikes oblong-cylindrical 2-3 cm long, ca. 1.5 cm wide, bearing 20-40 spikelets; leafy bracts 6 to 8, patent, lower ones surpassing corymb, lowest to 50 cm long. Spikelets spreading to reflexed, linear, subterete, 10-25 mm long, 1-1.5 mm wide, 10-25-flowered, yellowish green and yellowish brown at maturity; rachilla flexuous, winged, wings elliptic, first hyaline and eventually becoming more or less corky and tightly clasping nut.
• Glumes ovate-elliptic, obtuse, 2-3.5 mm long, yellowish and reddish brown striate, greenish obtuse costa 7-9-nerved. Achenes oblong to oblong-obovate, trigonous, 2/3 as long as glume, falling off tightly enveloped with rachilla wings together with rachilla internode and next higher glume; style shorter than achene; stigmas 3. Stamens 3.

分布

• 台灣 : Grasslands, waste places and waysides.
• 世界 : Pantropic.

引證標本

TAIPEI: Peitou, Faurie 74. TAOYUAN: Taoyuan, Shimada 663. YUNLIN: Huwei, Ashiri 2466. PINGTUNG: Ssuchungchi, Hsu 13550. TAITUNG: Chihpen, Koyama 6729; Lanyu Is., Sasaki s. n. Jun 1926, Kuoh 4810*. HUALIEN: Yuli, Yamamoto 3062, Kitamura 1708.

引用文獻

• KOYAMA, Tetsuo, KUOH, Chang-Sheng & LEONG, Wai-Chao, Flora of Taiwan, second edition 5: 315. 2000.  (Fl. Taiwan 2nd edit., 台灣植物誌第二版)