surveys for this report. Most sites are on 

 private land. Population information, including 

 size, elevation, location, and associated species 

 can be found in the Element Occurrence Record in 

 Appendix 5 . 



3. UNVERIFIED/ UNDOCUMENTED REPORTS: None. 



HABITAT 



1. ASSOCIATED VEGETATION: Astragalus convallarius var. 



convallarius is found in sagebrush and grassland 

 communities. In Montana it occurs in fescue 

 bunchgrass grasslands, such as Festuca scabrella - 

 Aqropyron spicatum . and Festuca idahoensis - 

 Aqropyron spicatum . The species is also found in 

 the Stipa comata - Bouteloua gracilis plant 

 association. On the Helena National Forest A. 

 convallarius var. convallarius occurs in a Festuca 

 scabrella - Aqropyron spicatum plant association 

 with Stipa viridula , Poa scabrella , and Astragalus 

 f lexuosus . 



2. TOPOGRAPHY: Rangewide Astragalus convallarius var. 



convallarius grows on hillsides, bluffs, benches, 

 and valley floors at elevations between 4150-9000 

 feet (Barneby 1964) . In Montana the plant has 

 been found on slopes and rolling uplands with 

 north or southeast aspects. Elevations at these 

 sites vary from 3880-4640 feet in the Helena area 

 to 8100 feet at the site near the Idaho border. 



3. SOIL RELATIONSHIPS: Astragalus convallarius var. 



convallarius grows in dry sandy, loamy, or clay 

 soils of various origin and composition, 

 apparently without preference as to rock 

 formation, but is found most frequently on 

 sedimentary formations (Barneby 1964) . In Montana 

 the species has been found on loamy or silty 

 soils. The Helena National Forest site was 

 discovered on silty soil derived from limestone 

 and calcareous sandstone. 



4. REGIONAL CLIMATE: The climate of west-central 



Montana can generally be classified as cool, dry, 

 and continental, with locally greater amounts of 

 precipitation in the mountains. The Astragalus 

 convallarius var. convallarius site on the Helena 

 National Forest is closest to the Holter Dam 

 weather station although the site is about 15 

 miles southeast of the station and is slightly 

 higher in elevation (3960 feet as compared to 3487 



18 



