BY IJUNDESHAGEN 157 



Ga is based on actual inspection of every stand, and either esti- 

 mated by cruising, or else as in 4a of above tables, by ascertaining 

 age and condition of stocking and then computing volume by yield 

 tables. ^ 



Gn is obtained by summation of Yield table as done in 3b of 

 .above examples. 



Yr is the stand of one acre r years old as per yield table. 



According to the above premises the cut in the small forest there 

 .assumed would be : 



Cut = 2110 (5600/146000) = 21 10 (1/26) = Ga (Cut on r 

 acres/Stock on r acres) =2110 (3.8%) =80 cu. ft. per acre. 



In this case then the yearly cut would take 80 cu. ft. per acre or 

 650 X 80 = 52,000 cu. ft. in all. Von Mantel evidently going on 

 the assumption that a little more or less in the estimate would not 

 change results in ordinary cases decided to use Normal Stock as 

 'Calculated from Yr and r, i. e., Yr X r/2 ; in our case 5630 X 60/2= 

 168,000 cu. ft. for 60 acres. 



In this way the formula is simplified to: 



Cut = Ga Yr/Gn = Ga Yr/YrX.r/2 = Ga 2/r 



which merely follows out logically the assumption of Hundeshagen ; 

 and is based on the fact that in a regulated forest the growth in the 

 forest during rotation equals twice the growing stock found at any 

 time on the land, as stated under Normal forest. 



In the assumed case then : Cut =-- 2Ga/r or 



Cut = 21 10 X 2/60 = 70 cu. ft. per acre, or about 10 cu. ft. 

 less than by the regular Hundeshagen calculation. 



Yon Mantel's Modification of Hundeshagen's formula is a very 

 useful devise to start the regulation on large wild woods properties. 

 It adapts the cut to the actual growing stock on the land, whether 

 this is in excess or below normal. 



In large properties stocked with pure stands of intolerants, 

 Western Yellow Pine, Lodge Pole, etc., where the stands are largely 

 even aged and where some of the Age Classes are practically want- 

 ing, application of either the Austrian or Hundeshagen Method 

 needs a careful consideration of actual existing conditions. 



What has been said with regard to the foregoing methods 

 ^applies here. This method merely estimates the proper cut to make 



