This contrasts with a field-oriented approach that 

 focuses on plant associations. This "ground up" 

 approach was used in keeping with the plant 

 associations of Bourgeron and Engelking (1995). Plant 

 associations and alliances represent the existing, on-site 

 composition as recognized in the National Vegetation 

 Classification Standard (Federal Geographic Data 

 Committee 1997), rather than a generalized mapping 

 unit. While the new federal standard establishes the 

 upper physiognomic classification levels nationwide, 

 the alliance and plant association (floristic levels) have 

 not been standardized and are in progress. The latter 

 are the levels at which targets are set. Most of the 

 detailed classifications are from western Montana 

 compared to eastern Montana (Pfister et al. 1977, 

 Hansen and Hoffman 1988, Hansen et al. 1995, 



DeVelice et al. 1995, Cooper et al. 1995). 

 Nevertheless, a synthesis of vegetation research results 

 from eastern Montana and adjoining states and 

 provinces provides a sound framework upon which to 

 build and incorporate the fijU breadth of Great Plains 

 plant community diversity. 



There has not been an interagency synthesis of RNA 

 information since the work by the Federal Committee 

 on Ecological Reserves (1977) at the national level. In 

 addition to all previously-mentioned objectives, this 

 project contributes new and standardized information 

 for incorporation into statewide, regional, and national 

 natural areas efforts and applications. 



