Herbs perennial, 5–50 cm, gla­brous. Stems erect or ascending, unbranched or several stems clumped from crown. Leaves palmate; stipules narrowly ovate, lanceolate, or linear-lanceolate, 1–2 cm, margins entire or toothed, apex acute; petiole 0.5–20 cm; petiolules 1 mm; leaflets 3, blades usually rhombic, oblong, or elliptic, sometimes ovate, 2.5–5 × 0.6–2 cm, base cuneate, veins slightly thickened, margins setose-serrulate, apex obtuse or retuse, surfaces glaucous abax­ially, glabrous. Peduncles straight, thick, 5–25 cm. Inflo­­rescences terminal or axillary, 30–70+-flowered, glo­bose or ovoid becoming subglobose, 1.5–4 × 1.8–3.3 cm, rachis prolonged beyond flowers, undivided or forked, often bearing sterile flower buds distally; involu­cres absent. Pedicels strongly reflexed in fruit, 1–1.5 mm; bracteoles minute. Flowers 11–14 mm, sweetly fragrant; calyx campanulate, gibbous, 4–6 mm, gla­brous, veins 5, tube 2–3 mm, lobes unequal, narrowly triangular or subulate, orifice open; corolla light pu­rplish, sometimes with pink tips, 10–13 mm, banner straight, obovate to broadly elliptic, 13–18 × 6–8 mm, apex rounded or retuse, apiculate. Legumes oblong, 5 mm. Seeds 2–4, reddish brown, flattened globose, 1.5–2 mm, smooth. 2n = 48.

Phenology: Flowering May–Jul.
Habitat: Moist, grassy meadows along streams.
Elevation: 1200–2000 m.

Distribution

• Generated Map
• Legacy Map

Calif., Idaho, Mont., Nev., Oreg., S.Dak., Utah, Wash.

Discussion

Disjunct populations of Trifolium beckwithii found in South Dakota are over 1200 km east of the nearest populations in Montana. The South Dakota populations appear to have been long-distance introductions from populations in northern California, based on molecular data (M. R. Duvall et al. 1999).

Selected References

None.

Lower Taxa

None.