56 PKELIMINAEY STUDY OF 



The relation of total height to clear length, showing the extent of self-pruning, 

 is also observable. The relative length of crown on the several types is exhib- 

 ited, and the greater sizes attained in the cove type than in the slope or ridge 

 type. 



The largest dimensions are attained along and west of the Allegheny and 

 Cumberland Mountains, in West Virginia, Kentucky, and Tennessee. Individual 

 specimens occasionally reach a height of 115 and 118 feet, and maximum diam- 

 eters of 50 and 52 inches. 



