生活型

herb

形態特徵

• Perennial herbs. Stems erect, 60–250 cm tall, rarely branched, densely leafy, coarsely puberulous nearly throughout.
• Basal leaves withered early, cauline leaves elliptic to lanceolate, apex acuminate or acute, base caudate to attenuate, short petiolate or nearly sessile, sparsely serrate and ciliate, with rigid short hairs, 6–15×1–3 cm, lower surface puberulous, midrib convex on lower surface. Heads in a terminal panicle, branches spreading or recurved. Peduncle 2–4 mm long.
• Heads numerous, 3–4 mm long, 2–3 mm across (excluding ligules), densely secund. Involucre campanulate, bracts 3 or 4 seriate, herbaceous, margins narrowly membranaceous, glabrous, outer bracts ca. 1.5 mm long, inner bracts gradually longer, to ca. 4 mm long. Ray florets: tube filiform, ca. 1.5 mm long, ligule linear to lanceolate, 2–3 mm long. Disc florets yellow, salverform, 2–2.5 mm long, 5-lobed.
• Achenes oblong, slightly curled, ca. 1 mm long, 0.2–0.3 mm wide, scabrous. Pappus bristles brownish white, subequal, numerous, in 1 row, 2.5–4 mm long, persistent.
• Chromosome number, 2n = 54 (Peng & Hsu, 1978).

分布

• 台灣 : occasional as a naturalized adventive around Taipei.
• 世界 : Native of N. America.

引證標本

TAIPEI: Liherlii, Peng 2588; Wutu, Peng 12983.

參考文獻

• PENG, Ching-I & CHUNG, Kuo-Fang; LI, Hui-Lin, Flora of Taiwan, second edition 4: 1064. 1998.  (Fl. Taiwan 2nd edit.)