Table 3. — Predicted versus observed tree loss by year based on Qi, the average probability of tree loss, by tree diameter 

 class and stand (Situation A, Klein and others 1978, grouped by greater diameter spread) 



Diameter 

 class 



Year of 

 infestation 



Number of trees 

 per acre 



Green 



Dead 



1/D, 



Predicted 

 tree loss 



6-12 inch 







198.3 



2.5 



0.4000 



0.997 



2.5 



(15.2-30.5-cm) 



1 



196.8 



3.2 



.3125 



.995 



3.1 





2 



193.6 



9.7 



.103 



.995 



9.2 





3 



183.9 



25.0 



.040 



.994 



21.7 





4 



158.9 



3.3 



.303 



.994 



2.6 





5 



155.6 



1.3 



.769 



.994 



1.0 





6 



154.3 



.3 



3.333 







.2 





7 



154.0 



















Total loss: 



44.3 

 {110.75/ha) 



Average: 



.995 



40.3 

 (100.75/ha) 



14-16 inch 







12.1 



1.0 



1.000 



0.917 



2.5 



(35.6-40.6-cm) 



1 



11.1 



1.9 



.526 



.906 



3.9 





2 



9.2 



3.8 



.263 



.869 



5.4 





3 



5.4 



2.4 



.416 



.783 



2.3 





4 



3.0 



.8 



1.250 



.679 



.5 





5 



2.2 



.3 



3.333 



.613 



.15 





6 



1.9 























Total loss: 



10.2 

 (25.5/ha) 



Average: 



.794 



14.8 

 (37.0/ha) 



>16-inch 





4.1 



0.6 



1.667 



0.768 



1.6 



(>40.6-cm) 



1 



3.5 



.7 



1.429 



.727 



1.7 





2 



2.8 



1.6 



.625 



.589 



2.0 





3 



1.2 



.4 



2.50C 



.363 



.3 





4 



' ■ .8 



.4 



2.500 



.177 



.2 





5 



.4 



.4 



10.000 



.056 



.03 





6 



.3 























-\ Total loss: 



3 8 

 (9.5/'ha) 



Average: 



.447 



5 9 

 (14.75/ha) 



7 



