Flora of North America species comparison

(7.5-)10-30 cm, from rhizomes, rhizomes horizontal.

0-2, ternate;

petiole 10-15 cm;

terminal leaflet sessile, ovate to rhombic, (2.5-)3-5(-6) × (2-)2.5-3.5 cm, base slightly oblique to broadly cuneate, margins crenate to serrate on distal 2/3, apex acuminate, surfaces abaxially glabrous, rarely puberulous on veins, adaxially usually glabrous;

lateral leaflets unlobed, rarely 1x-lobed; ultimate lobes (8-)10-20 mm wide.

1-flowered;

peduncle sparsely hispid or glabrous;

involucral bracts 3, 1-tiered, simple, ±similar to terminal leaflets of basal leaves, ovate, rarely rhombic, (2.5-)4-8 cm, bases distinct, broadly cuneate, margins crenate to serrate, or dentate on distal 2/3, apex acuminate, surfaces usually glabrous;

lateral leaves unlobed or occasionally 1x-lobed; ultimate lobes 8-15 mm wide.

sepals usually 5, white, ovate to obovate, rarely oblanceolate, (12-)15-25 × (8-)10-15(-20) mm, glabrous;

stamens 100-120.

body ovoid, swollen, 2.5-4 × 2-3 mm, not winged, proximally hispid, distally glabrous;

beak straight to subulate, 0.5 mm or less, glabrous.

spheric;

pedicel (5-)7-12 cm.

=14.