Monographs Details: Astragalus curvicarpus (A.Heller) J.F.Macbr. var. curvicarpus
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard. 13(1): 1-596.
Family:Fabaceae
Synonyms:Homalobus curvicarpus A.Heller, Astragalus speirocarpus var. curvicarpus E.Sheld., Astragalus speirocarpus var. falciformis A.Gray, Astragalus gibbsii var. falciformis M.E.Jones, Astragalus gibbsii var. curvicarpus (E.Sheld.) M.E.Jones, Astragalus whitedii f. speirocarpoides Barneby
Description:Variety Description - Usually stout, less often low and slender, the stems 1.5-4 dm. long; herbage loosely strigulose to villosulous with incurved, curly, or spreading hairs up to 0.250.5 mm. long, usually densely so, cinereous or sometimes greenish, the leaflets always, even if only thinly, pubescent above; calyx (7.9) 9.1-11.2 mm. long, the disc 1-1.4 mm. deep, the tube (6.9) 7.5-9.7 mm., long, (3.2) 3.9-4.8 mm. in diameter, the teeth (0.5) 1-2.3 mm. long; banner (15) 16.4-21 mm. long, the well-developed blade (5.6) 6-10.2 mm. wide, recurved through ± 45°; wings (14) 15-20.6 mm. long, the claws 7.6-10.7 mm., the blades 7-11.2 mm. long, 2.4-3.4 mm. wide; keel (11) 11.7-15.2 mm. long, the claws (7.4) 7.8-9.6 mm., the blades 4.9-6.2 mm. long, 2.7-3.3 mm. wide; stipe of the pod (9) 11-20 mm. long, the body 2-3.5 cm. long, (2.7) 3-4.1 (5.5) mm. in diameter, hamately incurved or coiled into a ring, villosulous or incumbent-strigulose, exceptionally glabrate in age, very rarely glabrous; ovules 18-25 (28); seeds 2.9-3.8 mm. long.

Distribution and Ecology - Sagebrush plains and foothills, in loose sandy or gravelly soils overlying basalt or granitic formations, sometimes forming extensive colonies on stabilized dunes, widespread and locally plentiful at (2750) 3100—6200 feet, from Honey Lake and the upper Klamath Basin in northern California eastward across transmontane Oregon to the Snake River Plains in southwestern Idaho, south across northern and westcentral Nevada, especially in the Humboldt and Reese River Valleys, to the east slope of the Sierra Nevada in Mono County, California, there ascending along the Walker River to 9200 feet.—Map No. 28.—Mid-April to July.

Discussion:The pod of A. curvicarpus is variable in curvature, most often bent inward into the form of a hook or sickle but sometimes crescentic. A pod coiled into a ring or even further, through one and a half spirals (= fma. speirocarpoid.es) is common in Lake County, Oregon, and in northwest Nevada, and has given rise in the past to records of A. speirocarpus from these areas. Occasional specimens combining either the small flowers of var. brachycodon with the pubescent fruit of var. curvicarpus (e.g., Cronquist 7845, from Lake County, Oregon, NY, RSA) or the characteristic large flowers of var. curvicarpus with the hairless fruits of var. subglaber (e.g., J. T. Howell 12,226, from Shasta County, California, CAS) are on record, but are interpreted as minor independent variants rather than as directly intergradient with the northern varieties of the species. The differential characters of the closely related A. Gibbsii, distributed along a peripheral segment of the range of A. curvicarpus, are mentioned under that heading.
Distribution:California United States of America North America| Oregon United States of America North America| Idaho United States of America North America| Nevada United States of America North America|