生活型

tree

形態特徵

• Deciduous trees, 20 m tall, 40 cm across; branchlets glabrous or slightly pubescent when young.
• Leaves alternate, elliptic, oblong to ovate-oblong, 6–12 cm long, 2–5 cm wide, acuminate at apex, broadly cuneate at base, glabrous or slightly pubescent when young, serrulate, lateral veins 6–7 pairs, midrib prominent beneath; petioles slender, 1.5–2.5 cm long.
• Staminate catkins at apex of branchlets, pendulous; bracts rhombic-rounded, each subtending 3 flowers; pistillate spikes at apex of old branchlets; bracts 3–4 mm long, woody, apex rounded, 5-lobed, each bract subtending 2 flowers; ovary 2-celled, each cell with 1 ovule; styles 2.
• Fruiting catkins 1–3 together, peduncled, about 1.5 cm long, cone-like, ellipsoid, persistent;nutlets compressed, with narrow wings, persistent, style remaining at the top.

物候

Flowering from autumn to spring.

分布

• 台灣 : widely distributed throughout the island at altitudes of 400–3,000 m; often forming pure stands, usually on river banks, in waste places or in exposed areas.
• 世界 : The Ryukyus.

引證標本

TAIPEI: Peihsinchuang, Shantsu, Yen 5392. HSINCHU: Luchangtashan, Fukuyama 38. NANTOU: Wushe, Lin & Tsai 13462; Shinmu village, Shinyi, Yen 4402. PINGTUNG: Peitawushan, Yang 31.

引用文獻

• LIAO, JIH-CHING, Flora of Taiwan, second edition 2: 44. 1996.  (Fl. Taiwan 2nd edit., 台灣植物誌第二版)