Astragalus albens
Bull. Calif. Acad. Sci. 1: 156. 1885.
Plants winter-annual, delicate, (2–)5–30 cm, silvery-strigulose, hairs basifixed. Stems prostrate to ascending, silvery-strigulose. Leaves (1–)1.5–4(–5.5) cm; stipules 1.8–3.5 mm, submembranous; leaflets (5 or)7 or 9, blades obovate, oblong-oval, or rhombic-obovate, 2–11 mm, apex subacute, obtuse, or emarginate, surfaces silvery-strigulose, appearing frosted. Peduncles ascending, 1.5–4.5(–8) cm. Racemes 5–14-flowered, flowers spreading to declined; axis 2.5–4.5(–8) cm in fruit; bracts 0.8–1.5 mm; bracteoles 0. Pedicels 0.8–2.5 mm. Flowers 7.3–9.5 mm; calyx 3.9–4.5 mm, strigulose, tube 2.2–2.7 mm, lobes subulate, 1.4–2.3 mm; corolla pink-purple; banner recurved through 40°; keel 7–8.4 mm, apex bluntly deltate. Legumes spreading to declined, green or purple-tinged becoming stramineous or brownish, incurved through 0.25–0.5 spiral, narrowly lunate-oblanceoloid, 3-sided compressed, 13–18 × 2.8–3.5 mm, thinly papery, strigulose; gynophore slender, 0.5–0.9 mm. Seeds 8–11.
Phenology: Flowering late Mar–May.
Habitat: Mainly on granitic or calcareous gravel.
Elevation: 1200–1900 m.
Distribution
Calif.
Discussion
Astragalus albens is one of the most narrowly localized astragali, restricted to, but common in, Cushenbury Canyon in the northeastern foothills of the San Bernardino Mountains in San Bernardino County. Similar to its relative A. mohavensis, A. albens is a short-lived perennial, usually flowering precociously, often persistent from season to season by dormant seeds (R. C. Barneby 1964).
Astragalus albens is in the Center for Plant Conservation’s National Collection of Endangered Plants.
Selected References
None.