Astragalus cremnophylax

Duration: Perennial Nativity: Native Lifeform: Forb/Herb General: Perennial, plants diminutive, cushion-like, essentially acaulescent; herbage silvery strigose with dolabriform hairs; caudex gnarled, closely branched, covered with persistent but withered leaf bases and stipules. Leaves: Alternate, odd-pinnate (sometimes sub-palmate), 0.3-3 cm long; leaflets 5-9, crowded, elliptic, obovate, or orbicular, 1-2.5 mm long, minutely strigose, margins entire, apex obtuse; stipules distinct, clasping; petiole short. Flowers: Inflorescence an axillary raceme, 2-10 flowered, usually shorter than the leaves; peduncle 0.5-3 (5) cm long; calyx 6-10.5 mm long, minutely strigose, the teeth 1.3- 2.5 mm long; corolla whitish or dingy white, the keel tip spotted or blotched, or all suffused with pale purple; banner 11-18.5 mm long, the wings slightly shorter; flowers May-July. Fruits: Legume, ascending, mostly lying on the ground, obliquely ovoid, 3-4.5 mm long, 2-3 mm in diameter, pale green or purple-dotted, densely strigose; legumes sessile. Ecology: Crevices and fissures in limestone; 2100 m (7000 ft); Coconino County (endemic to the South Rim of the Grand Canyon); southwestern U.S. Notes: Ours is var. cremnopylax, and is a federally listed endangered species. Astragalus gilensis (Gila milkvetch) is distinguished by its tufted to mat-forming habit, acaulescent or nearly so; herbage is silvery-strigose with dolabriform hairs; leaves are 2.5-9 cm long, with mostly 11-21 leaflets, these elliptic, oblong-elliptic, or oblanceolate, 3-12 mm long; racemes are densely 7-26 flowered, forming a sub-capitate cluster, peduncles 3.5- 15 cm long; corolla is pale-pink to pink-purple with white wing tips, the banner 6.2-10.4 mm long; legumes are ascending to spreading, ovoid to oblong-ellipsoid, 4.5- 7.5 mm long, reddish tinged and strigose. It typically occurs in sandy to gravelly soils, often under pines at 1800-2600 m (6000-8500 ft). Editor: Springer et al. 2008