Periodical Literature 111 



of the ageclasses in building up stock, and in the reHability of the 

 tables. The graphic method of analyzing the normal stock contri- 

 bution of different ageclasses can be most usefully employed for 

 comparing with actual stock conditions, and basing thereon espe- 

 cially periodic revisions of working plans. But for questions of 

 forest valuation and statics, the knowledge of the distribution 

 of the stock among sizeclasses of a working block is more to the 

 point. 



Upon the basis of extensive caliperings on sample areas of each 

 ageclass the data for the answer to this problem for spruce and 

 beech are tabulated by 4 cm classes and by five broader sizeclasses. 

 This is done for a rotation of 120 years, which can also be trans- 

 lated for a 100-year rotation. For the broader sizeclasses on a 

 medium site class in Swiss mountains, the data for spruce are 

 given as follows : 



1 = 1-20 years; 11 = 21-40 years, etc. 



Curves and graphic illustrations of this distribution show that 

 the beech behaves percentically very similarly, although the 

 absolute values differ greatly. 



On site I, the sizeclass 26-40 (10-16 inch) is for both species 

 most prominent with nearly 50 per cent.; on site III the two 

 middle classes 14r-40 (5-16 inch) are almost equally represented 

 with 40 per cent, each; while on site V, the second sizeclass 14-24 

 (5-10 inch) is the prominent one with over 40 in beech, and over 

 50 per cent, in pine. 



These data in a way incorporate the ideal aim of the manage- 

 ment regarding the wood capital quantitatively and qualitatively 

 which a working block should contain. All these data have 

 reference to pure, even-aged stand management. 



For selection forest, Flury, who is an advocate of the same, 

 acknowledges the lack of reliable data and the difficulty of securing 



