SILVICULTURE IN THE ADIRONDACKS 897 



D. b. h. D. b. h. Volume Volume Rate of 



Species. 1899. 1917. 1899. I9i7- increment.* 



(inches) (inches) (cu. ft.) (cu. ft.) (percent) 



Spruce 4-4 7-5 i-8 34 34 



Spruce 4-5 8.1 2.0 7.0 6.2 



Spruce 7-8 12.0 74 I74 4-5 ' 



Hemlock 11.6 16.3 16.6 26.O 2.5 



By using volume tables, and comparing the present volume with 

 that shown by the analysis of stumps to have been present in 1899, a 

 number of other spruces showed an average annual increment of 4.8 

 per cent. One specimen, disks from which were shown at the meeting 

 of the New York State Forestry Association at Lake Placid on Sep- 

 tember 7, 191 7, and which is now in the museum of the Department 

 of Forestry at Cornell, showed accelerated growth over a period of 

 18 years, and in the last ten years had grown at the rate of 5.67 per 

 cent in total volume. 



These figures are especially interesting at the present time, when 

 pulp wood is commanding such high prices. It shows what can be 

 expected of spruce when timely thinnings are made and the stand 

 opened to admit more light. 



John Bentley, Jr. 



For the sake of comparison, the same data were worked up by 

 diameter classes, figuring the current annual increment per cent (c. 

 a. i. per cent) by Pressler's formula and curving the results. From this 

 curve the following table is obtained : 



Current Annual Increment of Second-Growth Spruce. Spruce Flat Type, North- 

 western Adirondacks. 



(Read from Curve.) 



p. b. h. C. a. i. per cent Basis, 



(inches.) (Pressler). (Number trees.) 



6 6.6 5 



7 5.9 5 



8 54 19 



9 5.0 17 



10 4.6 9 



11 4-3 ID 



12 4-1 6 



13 3.9 



14 .. I 



Total 



72 



The volume table used was that given on p. 237 of Gary's Manual 

 for Northern Woodsmen, Table 6, in cubic feet, interpolating for frac- 



By Pressler's formula. 



