Flora of North America species comparison

10-40 cm, from rhizomes, rhizomes horizontal.

1, ternate;

petiole 10-25 cm;

terminal leaflet sessile, oblanceolate to ovate, (3.5-)4-7(-8) × 2.5-4(-6) cm, base broadly cuneate, margins coarsely serrate on distal 1/2-2/3, apex acuminate, surfaces ±glabrous;

lateral leaflets unlobed or occasionally 1x-lobed; ultimate lobes 8-25 mm wide.

1-flowered;

peduncle ±glabrous;

involucral bracts 3, 1-tiered, ternate, ±similar to basal leaves, bases distinct;

terminal leaflet sessile, oblanceolate to ovate, (2-)3-8.7 × 0.8-3 cm, bases narrowly cuneate to cuneate, margins coarsely serrate on distal 1/2 -2/3, apex acuminate, surfaces ± glabrous;

lateral leaflets unlobed or occasionally 1x-lobed; ultimate lobes 15-30 mm wide.

sepals (4-)5(-7), white, oblong to elliptic, (13-)15-20(-25) × 5-10 mm, glabrous;

stamens 50-70.

body elliptic, flat, 3.5-5 × 1-1.5 mm, not winged, puberulous;

beak straight or slightly curved, 1-1.5 mm, ±glabrous, not plumose.

nearly spheric;

pedicel (3-)4-8(-10) cm.