THE NORMAL AGE CLASSES. 



The area and distribution of the several age classes is as 

 follows : 



Coupe No. 1, oldest: 



Underwood = 10 acres = 20 years old. 



If now the underwood is arranged into four classes of 5 years 

 each, and the overwood into five classes of 20 years each, the 

 following areas are obtained for each class : 



Undenvood : 



G! = 1 5 years old = 5x10= 50 acres. 

 C n = 610 = = 50 

 (77/7=1115 = = 50 

 C IV = 16-20 = = 50 



Total A = 200 acres. 

 Overwood : 



Cf = 1 20 years old = 20 x 2 = 40 acres. 



C // =21 40 = = 40 



C 7 77=41 60 = = 40 



/r = 61 80 = = 40 



C v =81100 , = = 40 



Total A = 200 acres. 



