Introduction 



Southwest Montana and southern Beaverhead County in 

 particular are one of Montana's richest floristic regions with a 

 relatively high proportion of regional endemism (Lesica et al. 

 1984) . This area is geologically diverse, resulting in many 

 different soils, especially fine-textured and sandy calcareous 

 soils. Many species with Great Basin or Snake River Plains 

 floristic affinities reach the northern edge of their range here. 

 In addition there are numerous species that occur only in extreme 

 southwest Montana and adjacent Idaho and Wyoming. The Montana 

 Natural Heritage Program lists 41 species of special concern that 

 occur in southern Beaverhead County (Heidel 1995) . 



Much of southern Beaverhead County is public land managed by 

 the U.S. Forest Service and the Bureau of Land Management (BLM) . 

 BLM has jurisdiction over lower elevation public lands that 

 support the largest number of rare plants. It is necessary to 

 know which species are truly rare or endangered and where 

 populations of sensitive species are located in order to protect 

 biological diversity in this unique area. This report describes 

 the results of a sensitive plant survey of the Sage Creek area in 

 southern Beaverhead County. We describe the populations 

 encountered, evaluate the rarity of species of special concern, 

 discuss the ecological relationships of these plants, and make 

 management recommendations based on the acquired knowledge. An 

 additional goal of the study was to document the flora of Sage 

 Creek area. 



The Study Area 



Sage Creek drains an area of low mountains, south of the 

 Blacktail Mountains, west of the Snowcrest Range and east and 

 north of the Red Rock River in southern Beaverhead County (Fig. 



