pedatif idus in the Sweetgrass Hills. The dominant exotics 

 include: Bromus inermis , Agropyron repens and Phleum pratense . 

 Only the eastern fringe of the wetland has a native community and 

 is the part occupied by Ranunculus pedatif idus plants. The 

 localized native dominant appears to be Deschampsia cespitosa . 

 Associated species include: Castilleia cusickii , Potentilla 

 gracilis and Vicia americana . 



Vegetation is not described on either of the other two records 

 for the species in the state, but it to be expected to contrast 

 sharply with at least the Glacier National Park site where it 

 grows on matted fellfield vegetation above treeline. 



2. TOPOGRAPHY: The Glacier National Park site is on the summit of 

 East Flattop Mountain in a fellfield, while the Sweetgrass Hills 

 site is in a small perched wetland on a terrace just above the 

 base of West Butte. These two sites contrast markedly in 

 topographic position. 



3. SOIL RELATIONSHIPS: Soils are temporarily saturated mollisols 

 with a sandy loam texture. Like the preceding species, this one 

 is also near the contact between Colorado Shale Formation and the 

 Eagle Formation. 



4. REGIONAL CLIMATE: The Sweetgrass Hills as isolated nunatak has a 

 moderate climate compared to the semi-arid steppe climate of 

 surrounding plains, with additional precipitation and relatively 

 cool early-season growing season conditions. 



F. POPDIxATION DEMOGRAPHY AND BIOLOGY 



1. PHENOLOGY: The three Montana collection dates for this species 

 range from 2 June to 12 July. The two earliest collections dates 

 represent material in flower, including a 1 July collection made 

 at (8000 ft.) elevation. The Sweetgrass Hill specimen of 12 July 



- was collected in fruit. This population probably flowers by 

 early or mid June. 



2. POPULATION SIZE AND CONDITION: 



EG no. Population size 



001 Flathead Co., Columbia Falls; unknown 



002 Glacier Co., Glacier National Park; "uncommon" 



003 Toole Co., Sweetgrass Hills; 43 individual plants 



3. REPRODUCTIVE BIOLOGY 



a. TYPE OF REPRODUCTION: Reproduction is sexual and flowers are 

 monoecious. In light of genus adaptations for pollination 

 (mentioned below) , outcrossing is likely to be significant if not 



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