the stems and lea\'es of A. barrii are densely covered with short, white hairs. 

 Iridescent bluish-purple to pinkish-purple flowers arise on short stalks 

 throughout the mats on narrow, open, few-flowered inflorescences. The petals 

 are 7-17 mm long. The calyx is 3-5 mm long and densely covered with long, 

 white hairs. The sparsely white-hairy pod is narrowly elliptical, 4-8 mm long, 

 and 1-2 mm wide. 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 al. 1989). 



2. 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 suffruticulose caudex; herbage silver>'-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, 



ca. 2 mm long (adapted from Bameby 1956). 



3. LOCAL FIELD CHARACTERS: Specimens of ^. barrii can only be 

 determined with certainty from other species of Astragalus that have 

 compound lea\'es with 3 leaflets and mat forming habit when in flower. 

 Vegetatively, Astragalus barrii is similar to A. gilviflorus, A. hyalinus, A. 

 sericoleucus, and A. aretioides, and they overlap somewhat in their geographic 

 distributions. In the field, A. barrii is distinctive for its small, iridescent, 

 bluish-purple to bluish-pink flowers. 



Astragalus sericoleucus has pink-purple flowers with a paler horizontal band, 

 but the flowers are about one-half the size of A. barrii flowers. It is not known 

 from the Ashland District area, though occurs nearby in Big Horn County. 



The field characteristics of A. barrii are most similar to A. aretioides; however, 

 the latter has smaller flowers and is more densely mat-forming. It is not 

 known from the Ashland District, and is found at higher elevations in the Pryor 

 Mountains of Carbon County, Montana. 



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