生活型

herb

形態特徵

• Robust perennial, tufted, 80-100 cm tall; rhizomes black, short, up to 8 mm across; roots fibrous, reddish brown to black. Culms trigonous, glabrous, 50-70 cm tall, 3 mm wide.
• Leaves 3-6, up to 90 cm long; blades elongated linear, 30 cm long, 6-8 mm wide, flattish-plicate, herbaceous, scaberulous on distal margins; sheath 10-18 cm long, pale greenish, flushed with reddish brown at base. Anthela compound to decompound; leafy bracts 7-9, very unequal, erect-patent, spreading or reflexed, 5-60 cm long, 2-7 mm wide; primary rays 6-9, very unequal, 0-8 cm long, erect-patent; secondary rays short, up to 2 cm long; bracteoles lanceolate to ovate-lanceolate, 3-6 mm long, 1.5-3 mm wide.
• Spikelets clustered in 7-50 forming a globose head at apex of raylets, linear lanceolate, flattened, 6-12 mm long, 2-2.2 mm wide, densely 10-20 flowered; rachilla straight, 0.3 mm wide.
• Glumes ovate to ovate-lanceolate, 2-2.2 mm long, 0.8-1 mm wide, 3-nerved, straw-colored, the midrib green, apex scabrid. Stamen 1, filament 0.4 mm long, white, anther whitish yellow, 1 mm long, linear with subulate appendage at apex. Style green, 0.2 mm long, stigmas 3, 1.2 mm long, pale brown, ovary green, trigonous, 0.8 mm long. Achenes trigonous, beaked at apex, 1.5 mm long, 0.8 mm wide, brown, minutely puncticulate, conspicuously stipitate, the stipe broadened at base.

分布

• 台灣 : It occurs in the lowlands of the eastern and northern parts of Taiwan.
• 世界 : tropical America origin, but is now found in the United States, South Europe, Asia and Australia, also naturalized to Japan and the Ryukyu Islands.

引證標本

Hualien Co.: Gian Hsiang, Tzuyun Bridge, along Gian Hsi (River), 10 August 2001, Hua s. n. (NHU). Ilan Co.: Loutung, in back of Loutung Forest District Office, Forestry Bureau, along a wood-storing reservoir, 6 May 2006, Yu s. n. (NHU). Taipei Co.: Lujou Hsiang, along a branch of Tanshui River, in muddy ground, 10 May 2005, Huang s. n. (NHU).

引用文獻

• Shih-Huei Chen and Ming-Jou Wu, Taiwania 52(1): 60. 2007.