生活型

herb

形態特徵

• Perennial herbs, 50-80 cm tall, rhizomes white, 2-3 mm wide, covered with brown scales, terminated by a ovoid tuber; tubers up to 20 mm long and 5-10 mm wide, zonate. Culms trigonous, glabrous, 50-80 cm tall.
• Leaves 40-70 cm long, shorter than the culm; blades linear, 5-8 mm wide, flattish-plicate, gradually narrowed to acuminate apex; sheaths light brown.
• Anthela simple to compound, loose, 3-15 cm long, 2-10 cm wide; 2 to 10, slender, primary rays 1-12 cm long, patent; spikes sub-loosely bearing 3 to 10 spiklets; leafy bracts 6 to 9, rarely up to 10, mostly shorter than the anthela, the lowest overtopping and 2 to 3 times as long as the corymb, the second slightly surpassing the corymb. Spiklets spreading to patent, linear, acute at apex, 1-3.5 cm long, 1.5-3 mm wide, compressed, subdensely 8- to 28-flowered, yellow- brown; rachilla 1 mm long, 0.3 mm wide, winged. Glumes narrowly ovate, 3.5 mm long, 1 mm wide, 5- to 7-nerved, brown, the midrib green. Stamens 3, filament 3 mm long, white, anther linear, yellow, 1.5 mm long. Style whitish brown, 2.5 mm long, stigmas 3, brown, 2 mm long, ovary green, trigonous, 0.8-1 mm long.
• Achene trigonous, obovate-oblong, 1 mm long, 0.4 mm wide, brown, minutely puncticulate.

分布

• 台灣 : a weed distributed in sunny, wet, and dry habitats such as plantations, fallow land and the margins of paddy fields.
• 世界 : possibly a native of Europe and is now widespread throughout the tropical and subtropical regions of the world, also in North America north to Canada and Alaska, and also naturalized in Japan.

引證標本

Hualien City, Nanbin, along roadsides and borders of paddy fields, 28 April 2005, Chen s. n. (Herbarium, National Hualien University of Education; NHU); Sinhsing Rd., on traffic island, 10 July 2006, Chen s. n. (NHU); Gian Hsiang, Nanhua, along borders of paddy fields, 19 May 2006, Chen & Yu s. n. (NHU).

參考文獻

• Shih-Huei Chen and Ming-Jou Wu, Taiwania 52(1): 59-69. 2007.