Flora of North America species comparison

erect, glabrous, rooting at base, only very rarely rooting at proximal nodes.

erect or ascending from caudices, not rooting nodally, distally glabrous or brown-pilose, not bulbous-based.

basal and cauline, basal and proximal cauline leaf blades reniform to semicircular in outline, 3-lobed or -parted, 1-5 × 1.6-6.8 cm, base truncate to cordate, segments usually again lobed or parted, sometimes undivided, margins crenate or crenate-lobulate, apex rounded or occasionally obtuse.

reniform to broadly triangular in outline, 3-foliolate or deeply 3-parted, 1-4 × 1.6-4.4 cm, leaflets or segments 1-2x-parted, ultimate segments elliptic to oblanceolate or almost linear, margins entire or occasionally with 1-2 teeth, apex rounded to obtuse.

receptacle pubescent or glabrous;

sepals 3-5, reflexed from or near base, 2-5 × 1-3 mm, glabrous or sparsely hirsute;

petals 3-5, 2-5 × 1-3 mm;

nectary on petal surface, scale poorly developed and forming crescent-shaped or circular ridge surrounding but not covering nectary;

style absent.

receptacle glabrous or brown-pilose;

sepals spreading, 7-12 × 4-9 mm, brown-pilose;

petals initially white, usually becoming red with age, 9-15 × 7-14(-18) mm.

ellipsoid or cylindric heads, 5-13 × 3-7 mm;

achenes 1-1.2 × 0.8-1 mm, glabrous;

beak deltate, usually straight, 0.1 mm.

roots absent.

heads hemispheric, 5-8 × 7-16 mm;

fruit wall smooth, not veined, loose but not inflated, winged along suture, fruits winged achenes;

achenes 2.6-3 × 1.4-2 mm, glabrous;

beak persistent, lanceolate, 0.8-2.3 mm.