There are fifteen Research Natural Areas (RNAs) on National Wildlife 

 Abstract Refuges administered by the U.S. Fish and Wildlife Service in Montana. Each 



was inventoried for significant ecological and botanical attributes: outstand- 

 ing plant association examples, rare plant associations, and Montana plant 

 species of special concern. Two more study sites with existing or prospective 

 special management designation were also considered in the inventory work. 

 Biodiversity and representativeness information was prepared for each study 

 site, including a profile of all well-developed and uncommon native plant 

 associations, description of any rare plant species populations, and a summary 

 of biodiversity significance that incorporates this new data with original 

 RNA designation records. Related information was compiled to help put 

 results in context for each site, including description of environment, land 

 use, management notes, and recognized non-biological values. 



As a result, ten outstanding plant association examples, four rare plant 

 associations, and four Montana plant species of special concern were docu- 

 mented within twelve of the study sites. Most of the study sites are located in 

 the Great Plains, complementing one another and generally representing 

 biodiversity features not otherwise under special management designation in 

 Montana. These include riparian and dune systems, once-widespread grass- 

 land plant associations that have been drastically reduced elsewhere and rare 

 grassland plant associations that have not been reported in Montana before, 

 uncommon forest and woodland plant associations, and suites of successional 

 habitats associated with black-tailed prairie dog colonies. Individually and 

 collectively, these RNAs help anchor the conservation of Great Plains natural 

 environments and their component plant associations and species. 



We recommend additional surveys that extend beyond current RNA bound- 

 aries to identify areas that would fill gaps and achieve representation at scales 

 more consistent with ecological processes and the historic nature of once- 

 widespread vegetation types. The greatest potential for such areas is in the 

 Charles M. Russell NWR and on surrounding public lands, which offer 

 unique opportunities for identification and conservation of representative 

 large-scale landscape systems. 



