生活型

herb

形態特徵

• Annual or biennial herbs. Stems unbranched or 1 or 2 branched from base, 15–35 cm tall.
• Basal leaves in rosettes, withered but persistent at anthesis, oblanceolate to spatulate, narrowed into a petiole-like base, 15–30×5–15 mm, apex obtuse, mucronate, margins entire or slightly wavy, upper surface green, cottony, midrib hardly sunken, lower surface densely white woolly, midrib green, raised; cauline leaves remote, gradually diminishing in size upward, linear-oblong to spatulate, becoming folded and sickle-shaped upward. Spikes compact, terminal, to 4 cm long, occasionally with 1–3 axillary clusters below terminal spike; subtending leaves equal to or longer than spike.
• Heads 4.5–5×4–5 mm when dry, almost wholly invested in loose wool when young, upper half becoming glabrous at maturity. Outer involucral bracts ovate-lanceolate to lanceolate, apex acute; innermost ones linear-oblong, apex short acuminate. Central florets 4 or 5, corolla ca. 3 mm long; outer florets many, corolla ca. 3 mm long.
• Achenes oblong, ca. 0.7 mm long. Pappus connate into a ring, ca. 2.5 mm long.

分布

• 台灣 : waste fields at low elevations.
• 世界 : Probably native to the southern United State and widely adventive elsewhere.

引證標本

TAIPEI: Campus of Natl. Taiwan Univ., Peng 2580; Tanshui, Hsu 4365. NANTOU: Meifeng, Peng 2252. TAINAN: Yuching, Kao 6617. TAITUNG: Chupang, Kao 14227.

參考文獻

• PENG, Ching-I & CHUNG, Kuo-Fang; LI, Hui-Lin, Flora of Taiwan, second edition 4: 979. 1998.  (Fl. Taiwan 2nd edit.)