Performance parameters for A r a b i s f e c u n d a in spotted 

 knapweed removal (n=5) and control (n=5) plots at Bi 

 Creek (mean+SD). 



1987 



1988 

 Removal Control 



Removal Control Removal Control Removal 



Density ( p I a n t s / p I o t ) 16.0 + 3.9 21.2 + 6.5 58.0 + 59.2 24.0 + 3.7 32.6+12.9 



Fruiting plants/plot 8.8+2.9 8.0+A.5 1.2+1.3 1.4+2.1 11.2+5.3 



% plants fruiting 54.7+12.1 35.7+12.3 4.6+6.2 5.5+7.9 33.7+9.7 



New plants 50.4+60.3 13.6+8.6 16.8+6.3 



Dead plants 11.4+5.2 10.8+5.8 42.2+50.4 



Populationgrowth 2.67 0.27 -0.12 



# fruits/plot 55.6+26.4 39.2+16.9 18.2+18.6 8.0+10.7 348+169 



# inflorescences/plot 22.2+6.6 18.8+9.2 3.6+4.6 1.8+2.9 41.6+18.4 



Fruits/ inflorescence 2.4+0.6 2.4+1.1 6.5+3.1 5.9+2.2 8.6+2.9 



Inflorescence/fruiting 2.2+0.6 2.6+1.0 2.7+0.9 1.1+0.2 3.8+0.6 

 plant 



Control 

 17.2+10.3 



5.4+4.7 

 36.2+17.9 



7.8+5.4 

 14.6+5.9 



-0.28 

 139+168 

 22 .0 + 23.2 



5.7+1.9 



3.5+1.5 



