SIZE OF THE AGE CLASSES. 219 



Overwood on '2 acres = 41 years old. 



'■i „ = 81 „ „ 



The normal state of the age classes in the case of coppice 

 with standards is of a still more ideal character, than in the 

 case of the shelter- wood compartment system ; it can only 

 serve as a mathematical guide for the treatment of such woods, 

 as it gives some idea of the relative number of trees, which 

 should be found in each class or gradation. Each of these 

 should occupy about the same area ; hence, the youngest class 

 must contain a large number of trees, which is gradually 

 reduced to a comparatively small number in the oldest age 

 class. The actual proportion in these numbers depends on 

 the species and the quality of the locality. 



('. T/w /^eleriio/i Fares/. 

 If the annual cuttings extend over the whole area, then all 

 age classes are, theoretically speaking, represented in all parts 

 of the forest; if, on the other hand, the cuttings pass over the 

 forest in the course of a number of years, say /, then the age 

 classes will gradually become located similar to the distribution 

 of the overwood in a coppice with standards forest. The 



number of age classes will, theoretically, be equal to -^. 



Let A = 1,000 acres ; r — 100 ; Z — 20 ; then each annual 



cutting area = y = ' = 50 acres, and the distribution 



would approximately be as follows : — 



Coupe No. 1 {yomujest). Coupe No. 2. 



1 year old trees = 10 acres 2 year old trees == 10 acres 

 •21 „ „ „ = 10 „ 22 „ ,. ,, = 10 „ 



^1 M M „ = 10 „ ' 42 „ ,, ,, = 10 „ 



61 „ „ „ = 10 ,. ! 62 „ „ ,, == 10 „ 

 «1 „ „ ,- = 10 „ 82 „ ,, ,, = 10 „ 



Total = 50 acres Total = 50 acres 



