THE SWISS METHOD OF REGULATING THE CUT IN PRACTICE 565 



lock, beech, paper birch, maple, basswocd, ash, oak, and the popples 

 are all found in considerable quantities, both in mixtures and in pure 

 stands of varying sizes. In further contrast to the forests of the Cats- 

 kills the greater proportion of the timber, both in nimiber of trees and 

 volume exists in the size classes up to and including 16 inches d. b. h. 

 A relatively small proportion of overmature stock is on hand. 



Table 1. — Current Annual Increment Per Cents. Pressler's Formula. 

 p^Z^i'x — .^ Ulster County, New York. 



Hemlock 



[Read from Curves] 

 Beech 



Birch 



Ma pie 



D.B.H. Years to C.A.I. Years to C.A.I. Years to C.A.I. Years to C.A.I. 

 Inches grow 1 inch per grow 1 inch per grow 1 inch per grow 1 inch per 

 d. b. h. cent d. h. h. cent d. h. h. cent d. b. h. cent 



1 F= volume at certain diameter in inches; v= volume at next smallest diameter 

 in inches; n = number of years to grow this inch in diameter. 



Hardwood tables begin at 13 inches, hemlock at 7 inches d. b. h. The volume 

 tables used are listed on pages 6 and 7 of Bulletin 11, New York State Conser\-a- 

 tion Commission. 



In order to use the Swiss method to regulate the cut two sets of data 

 must be had; first the volumes of existing material, and second, the 

 current annual increment per cent. The former is seciu-ed from the 

 stock tables of the working plan; the latter by the use of Pressler's 

 formula^ or some other means of determining the current annual incre- 

 ment per cent.^ 



Tables 1 and 2 present the current annual increment per cent, the 



5 See Table 1. 



' E. g., Schneider's formula or the methods described bv B. A. Chandler in For 

 Quart., Vol. XI, No. 3, pp. 453-460 and J. G. Stetson, For.' Quart. Vol. VIII, No. 3." 

 pp. 326-331. 



