Astragalus kentrophyta var. elatus

Plants usually erect or assurgent, rarely trailing, suffruticose and often bushy-branched basally, forming low, prickly bushes, 10–45(–65) cm, sometimes mat-forming. Stems and herbage strigulose, hairs malpighian. Leaves (0.8–)1–2.6 cm; stipules dimorphic, those at proximal nodes connate with bidentate tip, those at distal nodes connate near base with spiny tips, 1–12 mm; leaflets (3 or)5 or 7, blades (2–)5–15(–17) mm, surfaces usually pubescent, sometimes glabrous adaxially. Peduncles 0.1–0.6 cm. Flowers 4.8–6.2 mm; calyx 3.4–4.4 mm, tube 1.8–2.3 mm, lobes subulate, spinulose, 1.5–2.4 mm; corolla usually whitish or faintly veined or tinged purple, fading ochroleucous, rarely pink-purple. Legumes narrowly ovoid-acuminate, (3.5–)4–7 × 1.5–2 mm. Seeds 2–4. 2n = 24.

Phenology: Flowering Jun–Sep.
Habitat: Mixed desert and salt desert shrub, juniper-pinyon, ponderosa pine, bristlecone pine, and pine-spruce communities, floodplains.
Elevation: 1500–2900(–3200) m.

Ariz., Calif., Colo., Nev., N.Mex., Utah, Wyo.

Discussion

Both erect and prostrate phases are known, which at maturity form ascending or sprawling tangles of untidy, branched stems with prickly leaves, hence an alternative common name of barb-wire kentrophyta. The prostrate phases, typically from upper-middle elevations, simulate var. tegetarius, which has basifixed hairs.

Selected References

None.

Lower Taxa