Prostrate to ascending, or erect, annual or short-lived perennial herb. Lvs glabrous or sparsely hairy, cuneately narrowed at base and often appearing petiolate, narrow-ovate, elliptic, oblong, or lanceolate, not lobed and entire, irregularly pinnately toothed, or lobed with many lvs usually pinnatifid with narrow to broad, entire or few-toothed, usually distant segments, 15-65-(110) × (3)-5-15-(60) mm; primary segments, lobes, or teeth (0)-3-6-(7) on each side. Uppermost lvs smaller, less divided, often amplexicaul. Supplementary bracts 6-16, 1-3 mm long. Involucral bracts (8)-10-13-(15), 4-6.5 mm long, usually glabrous, sometimes with a few scattered hairs. Ray florets 7-13 (extremely rarely 0); ligules yellow, (1)-2-7-(9) mm long. Disc yellow, 3-6 mm diam. Achenes usually densely hairy only between ribs, very rarely glabrous or ± evenly hairy, slightly narrowed to apex, 2.2-3 mm long.
Home