— 177 — 

 2) Any particular cycle of growth of stand V, G, iM^, h and D 



accords with the formula y=ke * where y is the amount of factors 

 which has been attained at time t, k is the ideal maximum total amount 

 of growth attained during the cycle and the constants k and k^ vary with 

 the quality of site and the form of density. 



(Ill) On the normal trend op the growth of stand 



GIVEN in the yield TABLE 



This part will be divided into two parts, one on the normal trend of 

 the growth of stands simultaneously surveyed and managed with same 

 manner of thinning and the other on the trend of the growth and yield 

 given in yield table. For simplicity and convenience, we will confine our 

 remarks to the last part and for illustration will discuss only the yield 

 table for spruce in Germany which was constructed by Dr. A. Schwap- 

 pach in 1890. 



The following diagrams (Plate XXVIII) [show the fluctuations of index 



numbers for the factors— V, G, —-— - — , H and D. From these diagrams, 



N 

 we see that these fluctuations are similar to one another with respect 



to the age, and differ only in their absolute values, so that the equation 



for each factor may be the same in form. 



Applying the equation y=ke we find: 



Spruce in the southern part of Germany. 

 Equation Probable % Diflf. 



logUj =1.7257 1^^^ ± 4.3% 



logKn = 1.691 1 — 2JLi^ ± 7.5% 



%Hni= 1.6562-^5:^ ± 9.8% 



%Hiv=1.6046-^?:?^?l- ±16.6% 



logKr = 1 .5083—11^^ ± 1 7.6% 



2. logVx =3.2471 -^°4^ ±6.0% 



%Vn =3.I870-^M1°°- ± 9.5% 



