Table 2 . Mean canopy cover of Centaurea maculosa in Centaurea 

 maculosa removal (treatment) and control plots at Birch Creek 

 (1987-90) and Charley's Gulch (1987-89) and Mann-Whitney tests 

 for significance. 1987 measurements were made before treatment 

 began. 



Control 



Birch Creek 

 Treatment 



1987 

 1988 

 1989 

 1990 



3 1 . 8+4 . 5 

 25.0+7.1 

 2 5.2+9.5 

 29.8+12.8 



28.2±5.6 

 2 6.0+5.5 

 10.0±5.0 

 13.4+6.8 



16 

 12 

 24 

 23 



0.46 

 0.81 

 0.02 

 0.04 



Year 



Charley's Gulch 

 Control Treatment 



1987 

 1988 

 1989 



