11 



Siliques were often observed to have been 

 grazed, apparently by small mammals. This 

 may aid in seed dispersal; however, it also 

 may lower fecundity. 



POPULATION ECOLOGY 



1. BIOLOGICAL INTERACTIONS 



a. COMPETITION: Most populations of A, fecunda 

 are too dispersed across the landscape for 

 intraspecif ic competition to be a factor. 

 However, interspecific competition between A. 

 fecunda and Centaurea maculosa is considered 

 to be a major threat to the four populations 

 along the flanks of the Sapphire Mountains. 

 Reports from an ongoing study of the 

 interactions between these two species at 

 these locations is contained in Schassberger 

 (1988, 1990). See also Hamilton and 

 Mitchell-Olds (1989) . 



b. HERBIVORY: Although A. fecunda does not 

 appear to be preferred by cattle, several 

 sites were heavily disturbed by the trampling 

 associated with grazing, and recently 

 extirpated plants were observed. 



Small mammals apparently graze on siliques; 

 unless this is excessive, it is probably not 

 detrimental to populations. 



LAND OWNERSHIP 



1. The land ownership for the 13 occurrences 



currently known in Montana is given below; several 

 of the sites occur in areas of mixed ownership 

 that include private. Bureau of Land Management, 

 and State of Montana lands. The exact locations 

 are provided in Sect. IV, pp. 17-38. 



U.S.D.A. Forest Service: 



i. Beaverhead National Forest 



Wise River Ranger District: 



Quartz Hill (005) 



Mouth of Quartz Hill Gulch ( 006) -portion 



Upper Quartz Hill Gulch (008) 



Canyon Creek (Oil) 



Cattle Gulch (013) 



