Astragalus hallii
Proc. Amer. Acad. Arts 6: 224. 1864.
Plants 12–50(–55) cm, strigulose to villosulous; from subterranean caudex. Stems decumbent, ascending, prostrate, or diffuse, 1–13 cm underground, villosulous or loosely strigose. Leaves 2–9 cm; stipules connate-sheathing and scarious at proximal nodes, distinct or connate by a low collar and subherbaceous at distal nodes, 1–7 mm; leaflets (11 or)13–27(–31), blades obovate to oblanceolate or elliptic, (1.5–)3–14(–15) mm, apex retuse, truncate, or obtuse, surfaces strigulose abaxially, sparsely hairy or glabrous adaxially. Peduncles suberect, incurved-ascending, spreading, declined, or prostrate, 3–9.5(–11) cm. Racemes (7–)9–28-flowered, flowers spreading-declined; axis 1–7 cm in fruit; bracts 1.5–5 mm; bracteoles 0–2. Pedicels 1.2–4 mm. Flowers 12.4–15(–18.5) mm; calyx campanulate, (5–)6–7(–9) mm, strigulose or villosulous, tube 5–6.2 mm, lobes triangular-subulate, 0.5–2.3 mm; corolla purple or reddish violet, sometimes white-tipped or suffused with purple; banner recurved through 45°; keel 9–12(–12.3) mm. Legumes spreading to declined, green or purplish becoming stramineous or brown, straight or slightly incurved, oblong, oblanceoloid-ellipsoid, ovoid, obovoid, or ellipsoid, slightly to distinctly inflated, (12–)13–27 × (3–)4–12 mm, cartilaginous becoming stiffly papery, somewhat fleshy opaque, glabrous, strigulose, or villosulous; stipe (0–)1–4.5 mm. Seeds 20–34.
Distribution
w United States.
Discussion
Varieties 2 (2 in the flora).
Selected References
None.
Key
| 1 | Legumes glabrous or sparsely strigulose, not distinctly inflated, narrowly oblong-ellipsoid, oblanceoloid-ellipsoid, or subclavately ellipsoid, (3–)4–7(–8.5) mm wide; herbage usually green, rarely subcinereous, villosulous or loosely strigulose, hairs to 0.5–0.8(–1) mm; primarily in Rocky Mountains and San Juan basins of Colorado and New Mexico, also ne Arizona, w Oklahoma. | Astragalus hallii var. hallii |
| 1 | Legumes usually strigulose, rarely villosulous, usually distinctly inflated, obliquely ovoid or obovoid, rarely ellipsoid, 6–12 mm wide; herbage often (not consistently) cinereous, strigulose, hairs to 0.2–0.4(–0.6) mm; Arizona, w New Mexico, sc Utah. | Astragalus hallii var. fallax |