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2. Topography: Four of the sites in Montana are in upland 

 positions on slopes and ridges in the foothills and the 

 fifth is in the basin of upper Big Sheep Creek. The 

 elevations range from about 5,900 to 6,900 feet. At 

 Bannack, chicken sage grows on the westerly facing slopes 

 and top of a limestone ridge at 6,200 to 6,400 feet. 



3. Soil relations: Soils at the Bannack site are shallow 

 gravelly clays derived from limestone. Chicken sage also 

 grows in cracks in the limestone pavement. 



E. Population demography and biology 



1. Demographic details: Estimates of population size in 

 Beaverhead County range from about 100 plants at upper Big 

 Sheep Creek, to thousands of plants observed in 1994 at each 

 of the Rocky Hills and Bannack sites. The Bannack 

 population was estimated to consist of between 1,000 and 

 10,000 plants and to cover about 40 acres. 



2. Reproductive biology: Reproduction is by seed. The 

 flowering period is in July. All plants seen at Bannack 

 were mature reproductive adults. The plants are probably 

 relatively long-lived. Plants at the nearby Rocky Hills 

 site were infected with a fungus, but its impact on 

 reproduction and survival are not known. 



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