5 

 1985) . Zonal vegetation surrounding the sites is foothills 

 Aaropvron - Festuca grasslands (Weaver 1980) with scattered Pinus 

 ponderosa and Pseudotsuga menziesii . The effects of trampling 

 and grazing by livestock are noticeable at both sites. At both 

 sites Aj. fecunda occurs in communities with a relatively low 

 density of vascular plants. 



Methods 



In 1987 we established a permanent belt transect consisting 

 of 10 adjacent 1-m 2 plots at each of the study sites following 

 methods outlined in Lesica (1987). Transects were placed in 

 areas with moderate to high cover of Centaurea maculosa and 

 Arabis fecunda . All Cj. maculosa plants were removed from five 

 randomly selected plots in each transect in late May of each year 

 by cutting the plants below the root crown using a sharp knife 

 with a hooked blade. We were careful to disturb the soil as 

 little as possible. 



Individual A_;_ fecunda plants were mapped and recorded using 

 the following system: 



S = plant with a single rosette < 2 cm diameter 

 R = plant with a single rosette > 2 cm diameter 

 S or R = a plant with x rosettes 



