Astragalus cyaneus

Title

Astragalus cyaneus

Authors

Rupert C. Barneby

Scientific Name

Astragalus cyaneus A.Gray

Description

200.  Astragalus cyaneus

Low but robust, acaulescent or nearly so, with a thick, woody taproot and shortly forking, at length knotty caudex, strigulose throughout with straight, appressed or subappressed, filiform or slightly flattened hairs up to 0.4—0.75 mm. long, the herbage cinereous or greenish, the leaflets pubescent on both sides, but of a brighter green beneath the vesture above; stems several, either reduced to crowns or a little developed and up to 6 cm. long, but always shorter than the leaves, and the internodes not over 1.5 cm. long; stipules pallid, papery or early becoming so, several-nerved, lanceolate, triangular, or triangular-acuminate, 4—9 mm. long, decurrent around ½ to the whole stem’s circumerence, free; leaves 6—18 cm. long, with stiff, grooved petiole and (15) 17-29 obovate to elliptic, obtuse, acute, or sometimes retuse, flat leaflets 4—19 mm. long; peduncles stout, (4) 6-13 cm. long, a little shorter than the leaves, ascending at anthesis, arcuately reclining or prostrate and radiating in fruit; racemes loosely (9) 12-22 (25)- flowered, the flowers loosely spreading or sometimes declined in age (but not characteristically nodding), the axis somewhat elongating, (2) 4-14 (20) cm. long in fruit; bracts thinly herbaceous becoming papery-membranous, lanceolate or linear-acuminate, 2.5-6 mm. long; pedicels erect or ascending, straight or nearly so, at anthesis 1-2.5 mm., in fruit clavately thickened, 2.5-4.5 mm. long; bracteoles 2, conspicuous or sometimes rudimentary; calyx 11.3-15 mm. long, strigulose with mixed black and white hairs, the oblique disc 2-2.8 mm. deep, the usually purplish, cylindric, or deeply and broadly campanulate tube 8.2-10.6 mm. long, 3.7-5.8 mm. in diameter, the subulate or lance-subulate teeth 2.3—4.6 mm. long; petals pink-purple, the banner with a pale, striate eye; banner gently recurved through ± 40°, spatulate-oblanceolate or ovate-cuneate, shallowly notched, 18-22 mm. long, 9.2-11 mm. wide; wings 17.9-21.9 mm. long, the claws 8.2-10.6 mm., the narrowly oblong, obtuse or obscurely emarginate, nearly straight blades 11.2-13.6 mm. long, 3.1-3.6 mm. wide; keel 16.3-18 mm. long, the claws 9-10.7 mm., the lunately half-elliptic or half-obovate blades 7.3-8.7 mm. long, 3.4-4 mm. wide, incurved through 90-95° to the bluntly deltoid apex; anthers 0.65-0.8 mm. long; pod ascending (humistrate), obliquely oblong-ellipsoid, 2.5-5 cm. long, 7-13 mm. in diameter, gently incurved, obtuse at base, obcompressed through the lower ¾ or more and thence passing upward into a triangular- or lance-acuminate, laterally compressed, cuspidate beak, openly sulcate along both sutures, both sutures prominent and cordlike, the ventral one stouter, the green or purple-tinged, thickly fleshy, strigulose valves becoming rigidly woody, strongly reticulate, stramineous or brownish, 1-2 mm. thick when fully ripe, inflexed behind the dorsal suture to ± the depth of the valve-wall, the septum forming a narrowly tubular or triquetrous cavity the length of the pod-body, the sutures subcontiguous within, the cross-section therefore didymous; dehiscence apical, tardy, after falling; ovules (35) 39-48; seeds brown, smooth but dull, 2.7-3.4 mm. long.—Collections: 10 (iii); representative: Heller & Heller (approximate topotypi) in 1897 (MINN, NY, POM); Ripley & Barneby 7550 (CAS, RSA, UTC), 7560 (CAS, NY, RSA, UTC); McKelvey 2375 (GH).

Dry hillsides and gullied banks, in sandy or gravelly granitic soils, commonly associated with piñon and juniper, 6900-7300 feet, locally plentiful but uncommon, known only from the east side of the Rio Grande Valley in Santa Fe, Taos, and possibly northeastern Bernalillo Counties, New Mexico.—Map No. 82.—Late April to June.

Astragalus cyaneus (dark blue, the petals sometimes turning so when dried) Gray in Mem. Amer. Acad. II, 4 (Pl. Fendl.): 34. 1849.—"148. Sante Fe, on gravelly hills and low mountains among rocks."—Holotypus, Fendler’s Pl. Novo-Mexicanae No. 148, collected in 1847, GH! isotypi, NY, PH, US!—Tragacantha cyanea (Gray) O. Kze., Rev. Gen. 944. 1891. Astragalus Shortianus var. cyaneus (Gray) Jones, Contrib. West. Bot. 8: 5. 1898, & op. cit. 10: 65. 1902. Xylophacos cyaneus (Gray) Rydb. in Bull. Torr. Club 52: 154. 1925.

Astragalus jemensis (of the Jemez Mountains, source of a paratypus which represents A. iodopetalus) A. Nels. in Amer. Jour. Bot. 21: 574. 1934—"Two sheets of Professor E. F. Castetter’s No. 332, collected between Golden and Madrid (Jemez Mts.) N. M., May 23, 1930, are taken as the type."—Holotypus, RM! isotypus, renumbered 6010, herb. Univ. New Mex!