J 62 



LOBLOLLY OE NORTH CAROLINA PINE. 



trees in the stand but their individual growth should have equaled that 

 of the predominant trees. Careful measurements have been made to 

 determine the area of the optimum crown space required for the growth 

 of dominant trees of different diameters (at different ages) on different 

 quality sites. Table 78 gives the crown sj^ace of dominant trees and 

 the distance between trees, while in Table 79 is given the number of 

 such trees of different diameters which would occupy an acre without 

 retarding accretion. 



Table 78. — Crown Space, Distance Between Trees and Index of Tolerance of Dominant 

 Trees of Loblolly Pine of Different Diameters on Different Quality Sites. 



The trees which enter into the crown cover can be so thinned as to 

 give each tree the optimum crown space required for that diameter : if 

 the crown space is less than the optimum (Plate XXVII), although 

 there are more trees per acre, the accretion of the individual tree is 

 retarded; if it exceeds the optimum the stand is understocked. (Plate 

 VI, A.) 



Table 79, to show yield of thinned stand and yield of thinnings, gives 

 the average diameter of the predominant trees in stands of different 

 ages on different quality sites; the number of such trees which could 

 occupy an acre as detemiined by the areas of their crown spaces; the 

 total yield of such stands, and the yield of the trees removed in thin- 

 ning ; the full value of the entire stand at different ages, and the value of 



