species have 3 petals, sepals, and stamens. A hand lens or microscope is necessary to 

 identify this diminutive species. 



C. GEOGRAPHICAL DISTRIBUTION 



1. GLOBAL RANGE: New Brunswick and Quebec to eastern Virginia; also 

 Missouri, Oklahoma, Montana. 



2. STATE DISTRIBUTION: Collected from a total of five locations, spanning 

 Cascade, Lake, Lewis and Clark, Powder River, and Teton counties. (Figure 

 17). 



3. STUDY AREA DISTRIBUTION: The one known District occurrence is east 

 of Yager Butte (Figure 17). Other similar buffalo wallows and a variety of 

 wetland habitats were surveyed without success. 



D. HABITAT 



1. ASSOCIATED VEGETATION: Associated with sparse, emergent 

 vegetation and with small, submerged species: 



Alopecurus aequalis 

 Eleocharis palustris 

 Limosella aquatica 

 Marsilea vestita 

 Navarretia intertexta 

 Plagiobothrys scolder i 



2. TOPOGRAPHY: The District site was a buffalo wallow on the flat ridgetop: 

 a small, shallow depression that completely evaporates before mid-summer and 

 was well over half evaporated at the time of the 1995 visit in early July 

 (Appendix E-12). Other sites in the state are similarly described as ponds and 

 mud flats. 



3. SOIL RELATIONSHIPS: The District site is on silt that is submerged early 

 in the season. The small basin was trampled throughout by livestock, and 

 American waterwort was present on dry points between hoof prints. One of its 

 other sites is described as an alkali pond (Cascade Co.), but none of its other 

 collection sites give an indication of the water chemistry. 



E. POPULATION BIOLOGY AND DEMOGRAPHY 



1. PHENOLOGY: Flowering occurs both below the water and after evaporation 



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