How Trees are Measured 



tree is a key to the rest. Take each kind of tree by itself. Cut 

 sixteen or twenty white oaks of different sizes and grown under 

 varying conditions at different places on the woodlot. Their 

 average will fairly represent the individuals of this species. Take 

 the tulip trees in the same way, and get the increase of the average 

 tree. When the different species have been considered separately, 

 they may be averaged to get the general per cent, of growth for all. 

 Then the owner knows about what amount of wood cut in a 

 winter will be replaced by the growth of the following summer. 

 The secret of success in the best-kept forests of Germany and 

 France is the management that does not cut m.ore than the 

 annual increase will restore. It explains the perennial vigour 

 and productiveness of these secular forests. 



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