Astragalus inflexus

Plants tuft-forming, caulescent, 15–40(–50) cm, villous or tomentose, hairs basifixed; from superficial caudex. Stems prostrate and radiating or with incurved-ascending tips, well developed, flexuous, villous or tomentose. Leaves (3–)4–12(–16) cm; stipules 5–12(–16) mm, submembranous; leaflets (9–)17–23(–27), blades obovate-cuneate, rhombic-oval, or broadly oblanceolate, (40–)60–160(–200) mm, apex usually acute, subacute, or shortly acuminate, rarely subobtuse, surfaces villous to tomentose. Peduncles divaricate or incurved-ascending, (2–)3–8 cm. Racemes (5–)8–18-flowered, flowers ascending; axis (1.5–)2.5–6(–8) cm in fruit; bracts 4.5–10 mm; bracteoles 0. Pedicels (1.3–)1.8–3.3 mm. Flowers (16.5–)19.5–23 mm; calyx usually purplish, cylindric or cylindro-campanulate, (9.4–)11.3–16.4 mm, villous, tube (6.2–)8.2–10.2 mm, lobes linear-lanceolate or lanceolate-caudate, 3.1–6.6(–7) mm; corolla pink-purple; banner recurved through 40°; keel (12.7–)14.4–17.2 mm. Legumes ascending, stramineous or brownish, ± straight proximally, incurved distally, obliquely ovoid, lanceoloid-ovoid, or oblong-ellipsoid, obcompressed, (13–)15–25(–30) × (5–)7–9.5 mm, unilocular, fleshy becoming stiffly leathery, villous-hirsute or tomentose; sutures approximate or contiguous within, cross section deeply cordate or subdidymous; sessile with gynophore (0–)0.7–1.8 mm. Seeds 22–28(–33). 2n = 22.

Phenology: Flowering Apr–early Jul.
Habitat: Open, grassy hillsides, dry pastures, valley floors, river terraces, on substrates derived from basalt or granite bedrock, rarely in ponderosa pine forests.
Elevation: (100–)300–1300 m.

Idaho, Mont., Oreg., Wash.

Discussion

Astragalus inflexus occurs in west-central Idaho, western Montana, northeastern Oregon, and south-central and southeastern Washington. It sometimes is confused with A. purshii var. glareosus, which was historically included within this entity, but A. inflexus has longer calyx lobes and a more strongly caulescent habit.

Selected References

None.

Lower Taxa