Plants annual or winter-annual, slender, delicate, (1–)8–11 cm, strigulose or glabrate, hairs basifixed; taproot slender. Stems incurved-ascending, strig­ulose or glabrate. Leaves 1.5–5 cm; stipules 1–3 mm, submembranous; leaflets (5 or)7–11, blades oblong-oblanceolate, obovate-cuneate, or cuneate, 2–8 mm, apex truncate or retuse, surfaces strigulose abaxially, glabrous or margins sparsely hairy adaxially. Peduncles ascending or incurved-ascending, 2.5–7 cm. Racemes loosely 2–5(–7)-flowered, flowers ascending to declined; axis (0.4–)0.7–2 cm in fruit; bracts 0.8–1.5 mm; bracteoles 0 or 1. Pedicels 0.5–1.5 mm. Flowers 5.4–10.5 mm; calyx 2.9–4.3 mm, strigulose, tube 2.2–2.9 mm, lobes subulate, 0.7–1.5 mm; corolla pink- or violet-purple, wings margined white, keel maculate; banner recurved through 40°; keel 4.3–5.8 mm, apex broadly deltate, sometimes minutely beaklike. Legumes deflexed, declined, or ascending (resupinate), mottled or suffused with purple, incurved, narrowly crescentic, bluntly 3-sided compressed, falling before splitting, dehiscent on ground, 12–20 × 2.6–3.4 mm, thin becoming papery, base round, strigulose or glabrous; bearing seeds near middle. Seeds 8–12. 2n = 24.

Phenology: Flowering Mar–early May.
Habitat: Moist, open sites, foothill oak woodlands, treeless summits, on igneous-derived, clay substrates from disintegrated lava rock.
Elevation: 40–1200 m.

Distribution

• Generated Map
• Legacy Map

Loading map...

Calif.

Discussion

Astragalus pauperculus differs from A. rattanii and A. tener by its comparatively loose fruiting racemes (often more than 10 mm) and is found along the western margin of the southern Cascade Range and the northern Sierra Nevada in Butte, Shasta, and Tehama counties.

Selected References

None.

Lower Taxa

None.