Description. 



A. General nontechnical description: Astragalus barrii 

 forms dense mats (cushions) , which rarely exceed 4 

 inches in height. Prostrate woody stems give rise 

 to numerous, leaves, each made up of 3 narrowly 

 elliptic leaflets. Both the stems and leaves of A. 

 barrii are densely covered with short, white hairs. 

 Iridescent bluish-purple to pinkish-purple flowers 

 arise on short stalks throughout the mats. In 

 Montana, this species blooms from late April to mid- 

 June, and later forms narrow, egg-shaped, one- to 

 few-seeded pods (adapted from Reel et ai. 1989) . 



B. Technical description: Perennial, low cushion 

 forming plant, up to 1.5 dm. (4.5 dm.) in diameter, 

 with stems reduced to leafy crowns that arise from a 

 closely forking suf f ruticulose caudex; herbage 

 silvery-strigose with dolabriform hairs up to 1.4 

 mm. long; stipules 4-8 mm. long, glabrous dorsally; 

 leaves 1-4 cm. long, the 3 leaflets linear- 

 oblanceolate, oblanceolate or elliptic-ovate, acute 

 or acutish, 3-12 mm. long; peduncles slender, 7-16 

 mm. long, and shorter than the leaves; raceme loose, 



(1) 2-4 flowered, with the fruiting axis up to 5-15 

 mm. long; calyx (4.6) 5.5-7.1 mm. long, the deeply 

 campanulate or subcylindric tube 3.6-5.1 mm. long, 

 the teeth (1.2) 1.5-2.4 mm. long; petals pink- 

 purple, the obovate-cuneate or broadly oblanceolate 

 banner (9.6) 10.5-16.7 mm. long; wings 9.1-13.5 mm. 

 long, the claws 4.1-5.5 mm.; anthers (0.45) 0.5-0.7 

 mm. long; pod narrowly lance-ellipsoid, 4.5-6.5 mm. 

 long, 1.2-1.8 mm. in diameter just above the rounded 

 base and tapering into a slightly incurved lance- 

 subulate beak about as long as the fertile portion, 

 obscurely triquetrous in the lower half, somewhat 

 flattened dorsally, the valves papery, silvery- 

 strigulose; ovules (7) 9-11; seeds (often only one 

 maturing) oblong, scarcely compressed, dull 

 purplish-green, smooth but not lustrous, about 2 mm. 

 long (adapted from Barneby 1956) . 



C. Local field characters: Astragalus barrii is most 

 easily identified in flower, and is distinguished by 

 its small bluish-purple to bluish-pink flowers, 

 compound leaves with 3 leaflets, and mat forming 

 habit. 



Vegetatively, Astragalus barrii is similar to A. 

 gilvif lorus , A. hyalinus. A. sericoleucus , and A. 

 aretioides , and they overlap in their geographic 

 distributions. Specimens of A. barrii can only be 



