noticeably more knapweed in 1995 than in 1987 when 

 initial surveys for The Nature Conservancy were 

 conducted (Lesica 1988) . If this plant continues 

 to spread it could outcompete and displace many 

 native species (Watson and Renney 1974, Harris and 

 Cranston 1979; Tyser and Key 1988), Castilleja 

 longispica among them. Leafy spurge (Euphorbia 

 esula) was observed along the road up Robertson 

 Draw in an area that had been burned. This 

 aggressive exotic may also pose a threat to 

 populations of C. longispica. 



The introduced grass, smooth brome (Bromus 

 inermis) , is present at both sites on the 

 northwest side of the Yellowstone area (Grayling 

 Power Pole, Grayling Arm Hebgen Lake) . This 

 species can be invasive and tends to exclude other 

 species. Smooth brome may pose a threat to 

 populations of C. longispica in the Yellowstone 

 area. 



3. RECREATION AND RESIDENTIAL DEVELOPMENT: Two of the 

 C. longispica populations occur on private land 

 near Hebgen Lake that is adjacent to newly created 

 residential areas (Grayling Power Pole, Grayling 

 Arm Hebgen Lake) . Both of these sites are 

 threatened by subdivision and housing development. 



B. MANAGEMENT PRACTICES AND RESPONSES 



1. LIVESTOCK GRAZING: The Robertson Draw area has 

 been deferred from grazing since 1988 to protect 

 elk winter range. All other populations of 

 Castilleja longispica in the Pryor and Beartooth 

 mountains are subject to cattle grazing. 

 Observations suggest that Castilleja longispica is 

 not adversely affected by cattle grazing and may 

 even benefit (see above) . Six of the Yellowstone 

 area populations (Cinnamon, Sheep Creek, Little 

 Mile Creek, Kirkwood, Elkhorn Ranch and Wapiti 

 Creek) are on cattle grazing allotments. Some of 

 the Pryor Mountain sites (Big Coulee, Tony Island) 

 may be subject to grazing by wild horses and two 



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