Periodical Literature 389 



made according to the prescription of the Association of Experi- 

 ment Stations which avoids all subjective determinations of stem 

 number, basal area, etc. The unforeseen result was that the dif- 

 ferences in all spacings are already more or less evened out as 

 far as basal area, volumes and also numbers are concerned, hence 

 from this time grow under similar conditions. These are given 

 in the following table, from which also the height grozvth appears, 

 contrary to generally accepted belief, to be favorably influenced 

 by open position. 



Full Strip Plats .85 1.13 1.42 1.70* 



Stem number 2963 2060 1688 1507 1521 1128 1327 



Height 9.6 11.0 12.2 U.O 14.2 14.7 13.9 



Basal area 19.64 19.71 21.53 24.05 25.86 22.96 25.19 



Diameter 9.2 U.O 12.8 14.3 14.7 16.1 15.6 



Volume, total 117.7 124.8 150.1 190.1 204.9 181.2 189.5 



Volume, stoutwood 89.4 108.7 140.0 181.4 196.6 175.5 183.0 



Form factor 624 .576 .571 .565 .558 .537 .541 



Value product 822 1196 1792 2594 2890 2826 2854 



* Area suffered from frost in juvenile stage. 



If the height had been adduced in making up the value factor, the 

 difference would have been still more favorable for the plantings. 

 At another place the author shows that shaft form also is not 

 best developed in a close but in a more or less open position, as 

 the form factors above indicate. 



On normal spruce sites and with early and severe thinnings the 

 superiority of wide spacing may perhaps not be so decided. 



One scientific fact of note results also from this experiment, 

 namely, the unreliability of the basal area as basis of a judgment 

 of production. 



Forstliche Tagesfragen. Tharandter Forstliches Jahrbuch, 1915, volume 

 66, pp. 129-154. 



In a discussion on "Forestal Questions 

 Thinning of the Day," by Dr. Borgman, in which the 



Results value of mensuration and especially studies 



of increment is pointed out and a plea is 

 made for greater interest of practitioners in the progress of ex- 

 perimentation and for saner interpretation of its results, the 

 author makes some interesting generalizations from the existing 

 yield tables used on thinned stands. In a footnote he gives the 

 full text of the instructions for thinnings issued by the Associa- 

 tion of German Experiment Stations. 



