‘ YIELD OF ASSOCIATED SPECIES 93 
It has been said that the species mixed with Spruce 
were callipered down to ten inches. In order to de- 
termine the number of trees per acre of diameters 
smaller than ten inches, twelve square acres, selected 
as a fair average, were surveyed, and the trees of all 
species other than Spruce were measured down to two 
inches. The following table gives the average number 
of trees of the small diameters found on these acres. 
