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To obtain future diameter outside bark (D , ) , the effect of bark growth must be 

 approximated. This can be done by multiplying the above expression for basal area 

 growth by the ratio of outside bark diameter to inside bark diameter. Tlien, ' 



%h - ''^oh ' ^^ohlh}?'" a. 273238 exp (Y)) 



In application, the user should measure a sample of bark thickness to establish the 

 ratio. If direct measurement is not possible, the average value of the ratio for the 

 trees in this study ('^^^j^'^ib ~ 1-077) can be used. 



The trends of diameter outside bark (i'^^) generated by repeated application of 

 the above equation to values obtained from solving equation 1, for several combinations 

 of site index, crown competition factor, and ratios of tree d.b.h. to diameter of tree 

 of mean basal area (d/D) , are illustrated in figures 2 through 4 of the Appendix. 



For a timespan of one decade, the curves are valid. For more than one decade, _ 

 the curves are only approximate because they ignore any natural change in CCF or d/D 

 that would be the consequence of growth and mortality among remaining trees in the 

 stand. Changes in the stand variables can be considered only by imbedding these 

 diameter growth equations in a stand growth simulation procedure. 



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