Flora of North America species comparison

decumbent to erect, 0.3–3 dm.

ascending to erect, (1.8–)2–6(–6.5) dm.

tightly to loosely cylindric, 1–15 cm; sheathing base glabrous abaxially;

petiole 0.5–4 cm, hairs 0.2–1 mm;

leaflets 10–35 per side, 1–8 mm, glabrous or short-hirsute, minutely glandular, lobes (2–)4–8(–10), linear to obovate or ± orbiculate, apex sometimes setose.

7–25(–30) cm; sheathing base usually sparsely strigose abaxially;

petiole 1–4(–5) cm;

leaflets 15–40 per side, ± flabellate, 3–14 mm, usually incised to base into 2–3 oblanceolate lobes, ± densely short-hirsute to -villous.

0–2(–3), not paired.

3–20(–25)-flowered, (0.5–)1–2.5(–3.5) cm diam.;

glomerules usually 1.

10–60-flowered, 4–15 cm diam.

(0.5–)1–7(–11) mm.

(1–)5–20 mm.

6–12 mm diam.;

epicalyx bractlets oblong to oval, 0.8–2.5(–3) mm;

hypanthium shallowly cupulate, 1–2 × 2.5–5 mm;

sepals (1.8–)2–4(–4.5) mm, obtuse to acute;

petals golden yellow, obovate, 2–5 mm;

stamens 5, filaments 0.8–2 mm, anthers yellow, 0.6–0.8 mm;

carpels (5–)8–15(–18), styles 1–3 mm.

9–14 mm diam.;

epicalyx bractlets lanceolate, 1–3(–3.3) mm;

hypanthium interior golden, 1–2 × 3–5 mm;

sepals (2.5–)3.5–6 mm, base golden adaxially, apex acute to acuminate;

petals yellow, linear to narrowly oblanceolate, 2–4 mm;

stamens 5, filaments 2–4 mm, anthers yellow, sometimes red-rimmed, oblong, 0.6–1.2 mm;

carpels 1–5, styles 2–3 mm.

greenish tan to light brown, 1.2–1.5 mm.

brown, 1.7–2.2 mm.