Astragalus strigulosus

Title

Astragalus strigulosus

Authors

Rupert C. Barneby

Scientific Name

Astragalus strigulosus Kunth

Description

15. Astragalus strigulosus

Coarse, leafy, caulescent perennial, with a taproot and (probably, but seldom observed) shortly subterranean caudex, strigose-pilosulous nearly throughout with rather stiff, subappressed or narrowly incurved-ascending hairs up to 0.4-0.7 mm. long, the herbage cinereous or canescent in youth, sometimes greenish in age, the leaflets glabrous or marginally pubescent above; stems erect and ascending in clumps, 2-6 dm. long (perhaps longer late in the season), simple or branched at several nodes from near the base upward; stipules 3-9 mm. long, more or less dimorphic, the lowest connate through half their length or more into a papery- scarious sheath sometimes ruptured or even deciduous in age, the upper ones longer, lanceolate or deltoid-acuminate, either connate at base, or semiamplexicaul- decurrent and free; leaves 4-10 cm. long, subsessile, with 13-23 (29) oblong- oblanceolate, broadly or narrowly oblong-elliptic, obtuse and mucronulate, retuse, or rarely subacute, flat or loosely folded leaflets 6-18 (22) mm. long; peduncles rather stout, erect or incurved-ascending, (4) 5-10 cm. long, a little longer or shorter than the leaf; racemes (12) 15-35 (40)-flowered, dense in early anthesis, the flowers early declined and retrorsely imbricated, the axis somewhat elongating, (1.5) 2-9 cm. long in fruit; bracts membranous, pallid, linear-lanceolate, (1.5) 2-4.5 mm. long; pedicels at anthesis 0.5-1 mm. long, early arched outward and downward, in fruit thickened, 0.8-2 mm. long; bracteoles 0-2, commonly 0; calyx (5.2) 5.8-7.5 mm. long, pilosulous with black, fuscous, or mixed black and white hairs, the oblique disc 0.6-1 mm. deep, the campanulate tube 2.8-3.2 mm. long, (2.2) 2.5-2.8 mm. in diameter, the slenderly lance-subulate teeth (2.5) 3-4.3 mm. long, the ventral pair often shorter than the rest, the whole becoming papery, marcescent unruptured; petals ochroleucous, immaculate; banner gently recurved through ± 40°, rhombic-obovate, obovate-spatulate, or elliptic-oblanceolate, shallowly or deeply notched, 9.2—11.5 mm. long, (4.2) 4.6—6 mm. wide; wings (7.7) 8.5-10.5 mm. long, the claws 3-3.5 mm., the narrowly oblanceolate, obtuse and erose, or obliquely truncate or emarginate, slightly incurved blades (5.5) 6-7.5 mm. long, (1.8) 2-2.5 mm. wide; keel 6.7-7.5 mm. long, the claws 3.1-3.5 mm., the half-obovate blades 4.2—4.7 mm. long, 2.1—2.6 mm. wide, abruptly incurved through 85-95° to the rounded, or more rarely deltoid and obtusely apiculate apex; anthers 0.4-0.55 mm. long; pod pendulous, stipitate, the stipe 2-4 mm. long, the body ellipsoid to plumply oblong-ellipsoid, 12-17 (20) mm. long, (4.5) 5-7 mm. in diameter, about 2—3 times longer than wide, straight or a trifle decurved, broadly cuneate at both ends, shortly apiculate-beaked, dorsiventrally compressed, low- carinate ventrally by the suture, openly sulcate dorsally, the thinly fleshy, green, glabrous or (rarely) white- or black-puberulent valves becoming rather stiffly papery, stramineous, cross-reticulate, inflexed as an incomplete or nearly complete septum 0.8-1.6 mm. wide; dehiscence basal and upward through the proximal half of the dorsal suture and the septum; ovules 14-18 (19); seeds brown or olivaceous, dull, smooth, 1.8—2.1 mm. long—Collections: 11 (o); representative: Rose, Painter & Rose 8835 (NY, US); Pringle 10,311 (CAS, GH, MICH, NY, P, US), 13,263 (GH, MICH, US); Matuda 21,883 (NY); E. W. Nelson 1940 (NY, US); Bourgeau 700 (G, P).