critical for protecting the biological diversity of this northern 

 outlier of intermountain desert vegetation. Protection should be 

 given to many of the areas supporting extensive, good-condition 

 examples of the six community types in group (1). Protection of 

 the Gyp Springs area that supports the Atriplex nuttallii - 

 Artemisia spinescens community type is particularly critical. 

 The eight community types in group (2) , Abies las iocarpa / Clematis 

 Columbiana , Pseudotsuqa menziesii - Cercocarpus ledif olius , 

 Juniperus osteosperma / Agropyron spicatum , Juniperus 

 osteosperma / Cercocarpus ledifolius . Pinus flexi lis - Juniperus 

 osteosperma , Artemisia pedatif ida / Agropyron spicatum , Aqropyron 

 spicatum /Cushion plant, and Carex rupestr is / Potent ilia ovina are 

 more common in the study area. Good-condition extensive examples 

 of these communities should be managed to maintain their 

 condition, and examples should be protected v;hen possible during 

 designation of special management areas designed to protect more 

 critical elements of diversity. 



Mapping of plant communities should be completed in order to 

 take community diversity into account. Using GIS, maps locating 

 rare plant communities could be overlaid on the existing rare 

 plant maps (Lesica and Achuff 1992) to better delineate the 

 boundaries of special management areas. This integrated approach 

 will provide an information base that allows managers to protect 

 biological diversity on multiple-use lands. 



ACKNOWLEDGEMENTS 



The authors gratefully acknowledge the financial assistance 

 provided by the USDI Bureau of Land Management (BLM) and the 

 Montana Natural Heritage Program. BLM assistance in locating and 

 assessing some of the field sites was greatly appreciated. Don 

 Heinze and Dan Bricco of the BLM were instrumental advocates for 

 this project and we extend our gratitude to them. 



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