Flora of North America species comparison

slender, erect, solitary or clustered, moderately or few-branched, from woody rootstock or rhizomes;

branches ascending at 20–45º, weakly or moderately zigzag.

slender, erect, clustered, many-branched, from rhizomes;

branches ascending at 20–45º, weakly to strongly zigzag.

stipules persistent, widely ovate or elliptic, 1.7–4.5 × 0.7–2.5 cm, base oblique to cuneate, apex acuminate or acute;

petiole 1–4 cm;

leaflet blades elliptic or obovate, 3.5–8 × 0.7–3(–5) cm, lateral veins 6–11 pairs, conspicuously net-veined abaxially or not, apex acute or obtuse, sometimes short-mucronate or emarginate, surfaces sparsely appressed-pubescent or glabrous.

stipules persistent, widely ovate to lanceolate, 1.5–6.5 × 0.7–5 cm, base cuneate to cordate or amplexicaul, apex acuminate;

petiole 1–3.5 cm;

leaflet blades elliptic, obovate, or rhombic, 3–7(–9) × 1.2–4(–4.5) cm, lateral veins 6–9 pairs, conspicuously net-veined abaxially, apex obtuse to acute, surfaces silvery-sericeous or tomentose to villous.

6–25-flowered, 4–25 cm;

flowers in whorls of 2 or 3 or scattered.

10–40-flowered, 7–30(–35) cm;

flowers mostly in whorls of 3–5.

2–8 cm;

bracts semipersistent, narrowly elliptic or elliptic to widely ovate, 6–10 × 2.5–6 mm.

2–10 cm;

bracts semipersistent, ovate to lanceolate, 6–15(–30) × 2.5–15(–20) mm.

3.5–5 mm, villosulous.

2–6 mm, sericeous or tomentose.

1.6–2.2 cm;

calyx 9–11 × 5–8 mm at limb, lobes 3–5 mm, shorter than tube;

wings and keel petals asymmetrically oblong-elliptic;

ovary velutinous or densely appressed-pubescent;

ovules 10–16.

1.5–2 cm;

calyx 5–9(–10) × 5–9 mm at limb, lobes 2.5–5 mm, equal to or longer than tube;

wing and keel petals asymmetrically oblong-elliptic or, sometimes, reniform (var. argentata);

ovary velutinous;

ovules 5–11.

ascending, straight, 4.5–6.5 × 0.4–0.6 cm, villosulous or appressed-pubescent.

ascending (irregularly divaricate when young), straight, 2–6(–7) × (0.5–)0.6–0.9 cm, sericeous, tomentose, or velutinous.

6–16, brown-black, oblong, 3.5–5 × 2.5–3 mm, beaked.

1–6(–10), brown, oblong, 4–5(–5.5) × (2.5–)2.8–4 mm, short-beaked.