Thermopsis divaricarpa

Herbs delicate, 3–6(–9) dm, glabrate or puberulent. Stems slender, erect, clustered, several-branched, from thick woody rootstock or rhizomes; branches ascending at 20–35º, weakly to moderately or strongly zigzag. Leaves: stipules persistent, ovate to narrowly elliptic, 2–3.5(–4) × 0.7–3 cm, base cuneate to cordate, apex acute; petiole 1–2.5 cm; leaflet blades elliptic to narrowly elliptic or rhombic, 3–7 × 0.5–2.5 cm, lateral veins 7–10 pairs, conspicuously net-veined abaxially, apex acute to obtuse, surfaces glabrate to puberulent. Peduncles 3–5 cm; bracts deciduous, ovate to lanceolate, 7–14 × 3–5 mm. Racemes 5–15-flowered, 7–15 cm; flowers usually in whorls of 2–4. Pedicels 5–8 mm, glabrate to puberulent. Flowers 2.5–2.9 cm; calyx 8–11 × 6–8 mm at limb, lobes 2–5 mm, equal to or shorter than tube; wing and keel petals elliptic to asymmetrically oblong-elliptic; ovary appressed-pubescent; ovules 10–18. Legumes divergent, straight to arcuate, to ca. 45º, 6.5–9 × 0.6–0.8 cm, inconspicuously appressed-pubescent. Seeds (6–)10–14, brown-black, elliptic, 4–5 × 2–2.5 mm, beaked. 2n = 36.

Phenology: Flowering (Apr–)May–Jun(–Jul).
Habitat: Pine or spruce forests, streamsides, moist, open areas.
Elevation: 2000–3000 m.

Colo., N.Mex., Wyo.

Discussion

Selected References

None.

Lower Taxa