Flora of North America species comparison

1–10+, ascending to erect, glabrescent to loosely villous [glabrous].

deciduous [persistent], basal and/or cauline;

stipules persistent, adnate to petiole or free, lanceolate to ovate, margins entire or serrate;

petiole present;

blade oblanceolate to obovate [or elliptic], 1–15[–35] cm, herbaceous [subcoriaceous], leaflets 2–12 pairs, elliptic, orbiculate, or obovate, margins flat, crenate, serrate, or incised, surfaces glabrous or hairy hairs unicellular to multicellular, acicular and/or gland-tipped.

terminal [or axillary] to distal leaves, [15–]20–100+-flowered, headlike spikes, glabrous or sparsely [to densely] pubescent;

peduncles present, sometimes absent;

bracts absent;

bracteoles present.

absent.

bisexual or pistillate (plants gynomonoecious [dioecious]), 2–4[–5] mm diam.;

hypanthium dry [fleshy, spongy], top-shaped, ellipsoid, or nearly orbicular, 2–9 mm, angled, winged, and/or ornamented with irregular flanges and papillae, tan to brown, hairy or glabrous;

sepals 4, distinct [basally connate], usually ascending or spreading, rarely slightly reflexed, ovate to elliptic;

petals 0;

stamens 0–30(–50), shorter or longer than sepals;

carpels [1 or]2(or 3), glabrous, styles repeatedly branched, brushlike.

achenes, 1 or 2[or 3], ellipsoid, 1.5–2 mm diam., glabrous (though reticulate and muricate);

hypanthium persistent, enclosing achenes;

sepals persistent, spreading to slightly ascending.

= 7.