Flora of North America species comparison

ascending to erect, (0.3–)1–3 dm, lengths 2 times basal leaves.

± erect, 2–4 dm.

2-ranked, ternate, (1–)3–12(–20) cm;

stipules: apex rounded;

petiole (0.5–)1–15(–18) cm, hairs and glands usually absent;

leaflets 3, central widely obovate to flabellate, (0.5–)1–5 × (0.4–)1–3(–3.5) cm, petiolule 0–5(–10) mm, margins flat, not or shallowly lobed (sinuses extending less than 1/2 to midvein), distal 1/2–3/4 usually unevenly incised 1/4–1/2 to midvein, teeth 3–7 per side, often secondarily toothed, surfaces similar, green, hairs absent or sparse, rarely common, 0.5–1 mm, glands absent or sparse.

pinnate, 12–20(–30) cm;

petiole 5–10(–15) cm, long hairs ± abundant, spreading to ascending, 0.5–1 mm, weak to ± stiff, short hairs abundant to dense, cottony or crisped hairs absent, glands sparse to abundant, often obscured;

leaflets 4–6(–9) per side, on distal (1/3–)1/2–3/5 of leaf axis, slightly overlapping, terminal ones oblanceolate to narrowly elliptic, 3–6 × 0.8–1.2(–1.5) cm, margins strongly revolute, incised ± 1/2 to midvein, undivided medial blade 5–9 mm wide, teeth 8–12 per side, narrowly triangular to lanceolate, surfaces ± dissimilar, abaxial grayish, long hairs ± sparse (or not differentiated from short hairs), 0.5–1.5 mm, weak, short hairs abundant to dense, cottony or crisped hairs absent, glands sparse or obscured, adaxial ± green, straight hairs (long and short not differentiated) abundant, spreading to ascending, 0.2–0.5 mm, cottony and crisped hairs absent, glands sparse to abundant, often obscured.

(1–)2–4.

1–6-flowered.

10–40-flowered, congested or elongating in fruit.

straight, 0.3–4.5(–5) cm, not much longer in fruit than in flower.

± 0.1 cm (proximal to 1.2 cm).

epicalyx bractlets often toothed or 2-lobed, elliptic to oval, 3.5–7 × (1–)1.5–3 mm, margins flat;

hypanthium 3–7 mm diam.;

sepals 4–8 mm, apex acute to obtuse;

petals dark yellow, (5–)6–10(–12) × (3–)5–10 mm;

filaments 1.5–3 mm, anthers 0.6–1.5 mm;

carpels 20–50, styles filiform, not or slightly papillate-swollen proximally, 1.6–2.5 mm.

epicalyx bractlets narrowly ovate-acuminate, (3–)4–8(–10) × 2–3 mm, lengths 1–2 times sepals, margins ± revolute;

hypanthium (4–)5–10 mm diam.;

sepals 3–5 mm, apex acute to obtuse, abaxial surfaces: venation moderate, glands ± abundant, obscured to evident;

petals pale yellow, 3–5 × 2–4 mm, lengths ± equal to or shorter than sepals;

filaments 1–1.5 mm, anthers 0.5–0.8 mm;

carpels 80–90, styles papillate-swollen in proximal 3/4+, 1–1.2 mm.

1.2–1.5 mm.

± 1 mm, ± rugose.

= 28.

= 14.