Western Yellow Pine Lands. 



489 



The annual growth on the tract at present, therefore, is about 

 400 M. feet, board measure. 



It is interesting to attempt to forecast probable future diameter 

 Hmits. For this purpose measurements of the crown areas of 216 

 trees were made, the following results being obtained : 



Comparison of Tables Number I and VII shows the areas re- 

 quired for the production of merchantable material by trees of 

 different diameters. The results may be arranged in the form 

 of a table : 



Table VIII. 



It will be seen that the eleven inch trees are the most productive 

 for the area occupied and it is probably safe to assume, allowing 

 an inch growth for quality, that the diameter limit of the future 



