METHODS 



Prior to fieldwork, the Biological Conservation Database (BCD) maintained by the Montana 

 Natural Heritage Program was queried for records of U.S. Forest Service - Northern Region 

 sensitive species (USDA Forest Ser\'ice 1994) known from the study area or from immediately 

 adjoining areas. All knowTi records of Barr's milkvetch {Astragalus barrii), the only current 

 sensitive species on the District, were retrieved. The U.S. Forest Service Regional list of 

 sensitive species was developed based on the best available botanical information at the time, 

 which was limited in the case of the Ashland District. Therefore, species on the Montana 

 Species of Special Concern list were also considered in the event that they could warrant 

 consideration for sensitive designation (Appendix A). Because of the limited botanical work in 

 this area, species of undetermined status which appeared to warrant consideration for addition to 

 the Montana list were also considered. 



Custer National Forest lands in the Ashland District were surs'eyed for sensitive plants in the 

 summer of 1995 by Hollis Marriott (May 22-31, June 11-27) and by Bonnie Heidel (July 3-13) 

 with the field assistance of Shannon Kimball in the latter period. Fieldwork conducted by 

 Marriott concentrated on potential habitat for Astragalus barrii and its semi-xeric to xeric 

 habitat, focussing especially upon early successional outcrops. Other habitat types were 

 sur\'eyed in the course of traversing the landscape between primary habitats. Sites were chosen 

 throughout the District, with the exception of the higher elevations and northerly slopes of the 

 divide north of the East Fork of Otter Creek. Towards the end of June, sur\'ey of mesic sites was 

 added as a priority. This proved to be somewhat early for many species of interest, due to the 

 unseasonably cool wet weather of 1995. Later fieldwork focused on woodland and wetland 

 habitats, with concerted efforts to relocate the Carex gravida historic collection site and resolve 

 the taxonomic questions associated with Sphenopholis obtusata var. major. The fieldwork 

 coverage is listed by quad map in Appendix B, along with maps of the general routes. 



Searches were conducted on foot in both known and potential habitats of target species, 

 including particularly large, intact, and/or well-developed habitat settings. Special attention was 

 paid to unusual habitats. Efforts were made to visit most large sectors of the study areas during 

 effective times of the field season. 



Field information was compiled on the Plant Species of Special Concern Survey Form, and the 

 populations were mapped onto U.S. Geological Survey topographic maps (7.5'). Data collected 

 included detailed information on vegetation, slope, aspect, soil, size of population, species 

 biology, and management considerations. Photographs were taken of target species and of their 

 habitats on color transparencies (35 mm slides), which are submitted with this report. 



Voucher specimens of the target species were collected so that there was at least one voucher per 

 county when adequate material was available, in keeping with the Montana Native Plant Society 

 collecting guidelines (1993). For target species with small populations, fragments of the plant 

 were collected for vouchers whenever possible. For tentative identification or for unknown 



