r.Y AUSTRUN METHOD 1 55 



Actual growth is calculated (as under 6-b, see above) on basis of 

 Average Yearly Growth of Ripe timber, in this case 68 cu. ft. per 

 acre. Actual Growing- Stock (Ga) is also calculated from Average 

 Growth of Ripe timber (as in 4-b of preceding tables) and is 2380 

 cu. ft. per acre. Normal Growing Stock per acre is Yr/2 or 2800 

 cu. ft. per acre (see 3a and 4c above). It is merel}' necessary now 

 to decide on a, the period during which this regulation should take 

 place. In this particular case there is not a surplus of Actual Grow- 

 ing Stock, but it is a deficit which should be corrected by saving in 

 the cut. The large area of twenty year old and of forty and fifty 

 year old stuff and the fair condition of these stands (stocking y+) 

 would indicate that there is no great need of saving heavily. For 

 this reason the saving up is spread over an entire rotation and it is 

 decided to make a = r in this case. Using the above data, then, the 



Cut ^68 -I- (2380 — 2800) /6o^ 68 — 7 = 61 cu. ft. per acre, 

 and for the forest of 650 acres the Yearly Cut is 39,650 cu. ft. per 

 year. 



The Austrian Method or Formula was not an invention of the 

 forester, but of an office man, and was introduced not for regulation 

 but for valuation of forest properties. 



It does not presuppose or prescribe any particular method of 

 silviculture, division, regularity of age c'asses, or any particular 

 order or sequence of the cut. The cut may be made at any point. 



But this method does not forbid forest division and order in the 

 work, and it is no fault, therefore, of this method that such improve- 

 ments are not prescribed in any particular plan. 



It can be applied to any forest and under any conditions, and 

 is particularly well suited to irregular wild woods in large properties 

 and to the Selection forest. It will at once set a reasonable cut, 

 prevent overcutting and work in the direction of order, and greater 

 regularity, not only of Growing Stock in Volume, but also of Age 

 Classes. Proof of the value of this method is given by the city 

 forests of Zurich where this method has long been in use, is pre- 

 scribed officially by the kanton government, and has led to perfect 

 regulation under the master hand of Director Meister. In these 

 forests in 1882 the period a of the formula was set at r (rotation) 

 or ninety years for Working Section I ; at forty years in Working 

 Section II ; and only twenty years in Section III of the Sihlwald. 



