1-4 mm long, not connate; leaflets 15-21, lance-oblong to 

 elliptic-oblong, 1.5-3.5 cm long, as much as 13 mm broad, 

 glabrous on the upper surface at least; peduncles mostly 

 10-15 cm long; racemes closely 15- to 30-flowered but 

 elongating and open in fruit; pedicels 2-5 mm long; 

 flowers spreading to slightly reflexed, white to 

 ochroleucous, about 2 cm long; calyx usually blackish- 

 hairy, 8-10 mm long, the narrowly lanceolate lower teeth 

 about 2 mm long; banner erect; wings 2-4 mm longer than 

 the keel; pod erect, with a stout upward-arching stipe 

 about twice as long as the calyx, the body 1.5-2 cm long, 

 cartilaginous, glabrous, slightly mottled, corrugate- 

 wrinkled, oblong-ovoid, inflated and slightly 

 obcompressed, 4-6 mm broad, 6-10 mm thick, with both 

 sutures sulcate, the lower intruded to form a 3/4 

 complete partition. 



3. Diagnostic characters: The following combination of 

 characters separates this from other Montana species of 

 Astragalus (adapted from Dorn 1984): 



Leaflets more than 5, not awl shaped 



Hairs attached at their base 



Stipules not united on side of stem opposite the petiole 



Pods stipitate, glabrous, obcompressed with the lower. 



suture nearly forming a partition within the fruit, 

 7-20 mm wide, less than 3 times as long as wide 



Calyx 8-12.5 mm long, banner more than 15 mm long 



B. GEOGRAPHIC DISTRIBUTION 



1. Species range: "Beaverhead County, Montana to Lemhi County 

 Idaho (Hitchcock and Cronquist 1973)." This species is a 

 regional endemic and has the narrowest global distribution of 

 all species surveyed in the Tendoy Mountains. 



2. Distribution in Montana: Beaverhead County, prior to this 

 study, known from six general localities (total 9 EOR's m the 

 BCD) in the drainages of Grasshopper and Medicine Lodge 

 Creeks. 



3. Occurrences in the study area: One population was found in 

 the vicinity of Johnson Gulch, in the northwestern part of the 

 range. 



C. HABITAT 



The Johnson Gulch population occurs on a dry, southwest 

 exposed slope in a Artemisia tripartita/Festuca idahoensis 

 community. Additional associates are Agropyron spicatum, 

 Antennaria microphylla, Carex filifolia, and Chrysothamnus 

 nauseosus. The soil is loamy and derived from limestone. 

 There was evidence of past grazing but the habitat was in 

 excellent condition. 



