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of trees measured. A similar curve was drawn for each of the other cross- 

 cuts above the stump. It has already been noted that the average stum]) 

 height was one and one-half feet. Therefore the curve for the top of the 

 first twelve-foot log represents the diameter growth at a point thirteen and 

 one-half feet above the ground. The same is, of course, true for the other 

 curves as well. 



These curves were then all transferred to one sheet in such a manner 

 that the growth at the respective crosscuts was shown on the basis of total 

 age, i.e., each curve begins as many years to the right of the intersection 

 of the two axes as it took the tree to grow t° the height of the crosscut in 

 question. These points are determined from the height growth table. 



These curves represent the diameter growth at their respective distances 

 above the ground, on the basis of total age (age at the ground), and not 

 on the basis of the age at the respective crosscuts. We are able to get from 

 this series of curves, for any age, the average total height and the dimensions 

 of the trees inside the bark at various points along the bole. 



A diameter breast height curve was also constructed in the following 

 manner. On the same sheet with the stump curve a second curve was drawn, 

 letting the ordinate represent diameter breast height values instead of diam- 

 eter inside the bark at the stump. Since there were but a small number of 

 trees, all of uniformly large diameter, it was impossible, as yet, to continue 

 this curve into the early age of the trees. But when the curves for the other 

 points on the bole were also transferred thus to a single sheet, the diameter 

 breast height height curve was prolonged by a process of interpolation to the 

 younger ages of the trees. 



