79 



Sd conlllt offZ.?^"?"- ^° '"i?^ " ^°'''' *^ •''^P^t'^'' ™^«" ^°™''"y constituted 

 woultt consist ot four age-classes, each occupjins one-fourth the total area Thus in 



rar'l0°890:au^f f °t ^T^ '"*' ^f ^S-^- would co^eroneTurth ofths 

 ffj ° l.^'S^O square feet. There would be no crops composed of trees over 2 

 feet m diameter, as m theory these would be exploited as soon as they reached th,t 



Class I, stems over 2 feet diameter, occupying 

 " ^^' " •> Is to 2 feet diameter, occupying 



•■ "i' " " 1 " n , 



" ^*^» " .. i „ 1 foot ,, 

 jj V, „ below i foot 



TOTAL 



43,560 



In order to ascertain the number of stems of each class, it woold be necessary to 

 measure the areas covered by the crowns of the average trees in each class. We will 

 assume these areas to be as follows :— 



Class I . 

 ., II . 

 =, III . 

 „ IV . 



„ V (dominant stems) 



900 square feet. 

 625 

 400 

 100 

 23 



The number of trees of each class, when the capital has been constituted, is 

 evidently the area covered by the class (10,890 square feet), divided by the average 

 area covered by one crown of that class ; and would therefore be as follows :— 



In the course of 30 years, according^ to the assumption made, all the trees in 

 each class attain the next higher class. If, therefore, during this inturval we fell the 

 difference in numbers the capital will remain unaltered. This operation may be 

 tabulated as follows : — 



At the end of the thirty-year period the crop on the ground would thus be the 

 normal capital. The place of the young growth in Class V at the commencement of 

 the period would be taken by a new stock of seedlings which would occupy one-fourth 

 of the area, i.e., the portion not covered by the standards reserved. 



This method is applied in the same way as the selection 

 method. The forest is divided into whatever number of 

 annual or periodic coupes the felling rotation requires, and 



