c. SEED DISPERSAL AND BIOLOGY: Unknown. 



F. POPULATION ECOLOGY 



1. COMPETITION: The restriction of this species to very sparsely-vegetated 

 habitats indicates that it may be a poor competitor and instead adapted as a 

 stress-resistant pioneer. Several of the smallest populations had heavy yellow 

 sweetclover (Melilotus officinalis) invasions, whose nitrogen-fixing capacities 

 may veer the course of competition and succession; others also had Venus 

 looking glass {Triodanis perfoliata) present, an adventive native species which 

 has become dominant over some outcrop slopes located farther north on the 

 District. 



2. HERBIVORY: None obser\ed. 



3. FIRE: This species' habitat would not carry a fire, though fire could expand 

 its potential habitat by setting back encroachment of woody species around the 

 periphery. 



G. LAND OWNERSHIP (MONTANA): The study area populations are all on the 



Ashland District of the Custer National Forest. The central Custer County collection 

 was made on the Fort Keogh Range Experiment Station, and the northern Custer 

 County collection was likely to have been made either on private land or on 

 BLM-administered land. 



H. ASSESSMENT AND MANAGEMENT RECOMMENDATIONS 



1. THREATS TO CURRENTLY KNOWN POPULATIONS: No direct 

 threats were identified. 



2. MANAGEMENT PRACTICES AND RESPONSES: Some of this species' 

 drainage course populations are dissected by roads that follow the drainages; in 

 these cases, road maintenance, weed problems, and weed control activities 

 could impact the species. The few populations with heavy sweetclover 

 invasion were in heavily grazed pastures, so that even while grazing is unlikely 

 to have a direct affect on its outcrop habitat, it may indirectly promote the 

 weed invasions that ultimately outcompete this species. 



3. RECOMMENDATIONS FOR MAINTAINING VIABLE 

 POPULATIONS: No special actions are currently deemed necessary. 



4. RECOMMENDATIONS FOR FURTHER ASSESSMENT: Survey work 

 for this species was conducted at a relatively late time that was unsuited for 



