Astragalus Kentrophyta var. danaus

  • Title

    Astragalus Kentrophyta var. danaus

  • Authors

    Rupert C. Barneby

  • Scientific Name

    Astragalus kentrophyta var. danaus (Barneby) Barneby

  • Description

    94b. Astragalus Kentrophyta var. danaus

    Densely matted or commonly mounded, the plants up to 15 cm. in diameter, the longest intemodes not over 5 mm. long, the foliage rigid and prickly, the leaves and stems loosely strigulose with narrowly ascending hairs up to 0.35-0.55 mm. long, silvery or greenish-cinereous; stipules membranous or scarious, 2.5-5 mm. long, the blades of the upper ones acerose; leaves 4-15 (20) mm. long, all or all but a few lower ones palmately trifoliolate, the leaflets 3-7 mm. long, the vulnerant spinule (1) 1.5-2 mm. long; peduncles 2-6 mm. long; calyx 2.4-3.2 mm. long, the tube 1.6-1.9 mm. long, ±1.5 mm. in diameter, the teeth 0.8-1.3 mm. long; petals pale purple, or whitish with purple keel-tip; banner 4-5.6 mm. long, 3.2-4 mm. wide; wings 3.8-5 mm. long, the claws 1-1.6 mm., the blades 3-3.2 mm. long, ± 1.4 mm. wide; keel 3.3-4.1 mm. long, the claws 1.3-1.8 mm., the blades 2.4—2.6 mm. long, ±1.5 mm. wide; pod subsymmetrically lenticular, 3.5—5 mm. long, 2—2.5 mm. in diameter; ovules 5—8.—Collections: 9 (o); representative: Sharsmith 2931, 11,408 (NY); Eastwood 547 (CAS); Raven 9864 (CAS, RSA); Alexander & Kellogg 4058 (NY, WS).

    Open gravelly slopes and talus upward from timber line, perhaps descending rarely into bristle-cone pine forest, (10,000) 11,000-12,000 feet, on either granite or metamorphic bedrock, possibly sometimes on pumice, local along the crest and east summits of the Sierra Nevada in Mono County (Sweetwater Mountains; Dun- derberg Peak south to Mono Pass) and on the Fresno-Inyo County line at Sawmill Pass.—Map No. 37.—July to September.

    Astragalus Kentrophyta var. danaus (Barneby) Barneby in Leafl. West. Bot. 5: 154. 1951, based on A. tegetarius var. danaus (of Mt. Dana) Barneby in op. cit. 5: 95. 1951.— "California: Glacier Canyon, Mt. Dana, Mono County, J. T. Howell 20,256 ... "—Holotypus, CAS! isotypus, RSA!

    Compared with var. implexus, as this occurs in the White Mountains on the opposite side of Owens Valley, the Sierra kentrophyta is a more rigid plant, the closely forking, basally indurated stems forming small, compact, prickly tufts or domed cushions rather than the prostrate mats of its common relative. The palmately trifoliolate leaves are characteristic, although some quinquefoliolate ones often occur low on each yearly segment of the gradually elongating caudex-branches. The var. danaus was first collected in 1863 near the summit of Mt. Dana by William H. Brewer (No. 1736, GH).