GEOGRAPHIC DISTRIBUTION 



1. Species range: from the Great Plains in South Dakota, 

 east to the Great Basin extending to Oregon and 

 California, and south to Mexico (Cronquist et al . 1977). 



2. Montana distribution: Carex vallicola is known from 9 

 sites widely distributed in southern Montana, in 

 Beaverhead, Carbon, Lewis and Clark, Madison, Silver Bow, 

 and Gallatin (or Park) counties. Four of these sites are 

 in Beaverhead County. Two occurrences are known only by 

 historical collections (1908 and 1921) and few have been 

 thoroughly surveyed. 



3. Occurrences in the Tendoy Mountains: The species was 

 collected but not fully surveyed on the Beaverhead 

 National Forest in the vicinity of Sourdough Spring 

 (010). An Element Occurrence Record and map showing the 

 precise location of the population is included in 

 Appendix D. 



1. Associated vegetation: In Montana, Carex vallicola is 

 generally found in grasslands with or without sagebrush, 

 but at two northern and eastern sites it was reported 

 from Douglas fir forests. In the Intermountain Region it 

 often grows under aspen (Cronquist et al . 1977). The 

 population on the Beaverhead National Forest in the 

 Tendoys occurs in an Artemisia tridentata/Festuca 

 idahoensis association with Castilleja rustica, Eriogonum 

 umbellatum, and Lupinus argenteus . 



2. Topography: Throughout its range, Carex vallicola 

 inhabits slopes from the foothills to moderate elevations 

 in the mountains (Cronquist et al . 1977). In Montana, it 

 is reported from gentle to moderate slopes of various 

 aspects in the foothills and mountains, at elevations 

 ranging from 5,870 to 8,500 feet. In the Tendoys, the 

 population is on a moderate, south facing slope at 8,500 

 feet, in a bowl at the head of a drainage below the crest 

 of the range. 



3. Soil relationships: In Montana, Carex vallicola is known 

 from dry to moist, relatively fine textured soils derived 

 from parent materials of limestone and alluvium. 



E. POPULATION DEMOGRAPHY AND BIOLOGY 



1. Demographic details: As mentioned above, the population 

 in the study area was not fully surveyed, however, the 

 population density was locally high enough that the 



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