22 
E. Tue Fina OBJEctTIve 
From the previous discussion of ash, it was seen that the 
greatest diameter class gives the greatest return. However, 
since the 13” class in ash was not frequently found, it is as 
yet doubtful if this diameter can generally be produced in 
seventy years. The next class, the 12”, is abundant. The age 
of this class was between sixty-five and seventy years. 
Sample trees which were felled showed that a diameter of 
11.6” was produced in sixty-five years. At the same rate of 
growth occurring during the previous five years, a diameter of 
12.4” would be produced in seventy years. These sample 
trees had clear boles of fifty-five feet. In Table VI the 12” 
diameter was associated with a crown radius of 8.7. From a 
graph of crown radii against diameters of stem we find that a 
diameter of 12.4” would be associated with a crown radius of 
9.1 feet. 
We may say then that the trees of the final harvest of ash 
at seventy years would average 12.4” diameter, 9.1 feet 
crown, fifty feet bole, and a height of eighty-two feet. 
In the case of oak where the bole gradually decreases with 
increasing diameter, the difference between clear length of 
bole and length of trunk to first living branch is very great, 
especially in the medium diameter classes. In ash this dif- 
ference is small. Hence in oak with each diameter class there 
is a great variation in length of bole, and this variation 
diminishes as diameter increases. That portion of the bole 
which bears dead branches could be greatly reduced if the 
forest were adequately stocked in ‘its early life. 
Boles fifty feet in length occur, and this is the desirable 
length. The largest clear bole found in oak was fifty-four 
feet, while the longest in ash was sixty-eight feet. It may be 
said in passing that if a clean bole of fifty feet can be obtained 
on a ten-inch tree it can be secured for the higher diameters 
and later years. 
If the trees in Table VIII be. grouped by length of clear 
bole we get the results given in Table XV. 
