Periodical Literature 123 



tion and the largest number surviving (although the difference 

 was not very great). Also the quality of the plants as regards 

 root development and stem from this depth was best, but in 

 weight the 2 cm and 8 cm produced the heaviest per hundred, and 

 the latter the heaviest total weight. The 2 cm depth produced 

 fewer, but good plants. The plants from greater than 4 cm 

 depths showed a smaller number, a poorer development, and 

 those from 10 and 12 cm depth, especially the latter, a much 

 smaller weight. The author concludes that 4 cm (less than 2 

 inch) is the best depth, on lighter soils more, on heavy soils less. 



Wie tief soil man Saateicheln legen? Zeitschrift fur Forst- und Jagdwesen, 

 October, 1915, pp. 601-4. 



Kubelka's article on experimental thin- 

 Thinnings nings of Douglas fir, which constitutes Part 



in 2 of Bulletin XXVIII of the Austrian Ex- 



Douglas Fir periment Station at Mariabrunn, is re- 

 viewed by Dr. Wimmer. 

 The thinnings were made in a stand of Douglas fir planted 

 1.3 X 1.5 meters apart in 1887 at an elevation of 600 meters on 

 sandstone formation. In 1905, when the stand was 18 years old, 

 thinnings of 3 grades were made : 



I — light thinnings (par le haut) in the dominant 

 II — medium thinnings (par le has) in the subdominant 

 III — heavy thinnings {par le has) in the subdominant. 

 Kubelka concludes that a heavy thinning results in the great- 

 est increment, and therefore recommends that Douglas fir be 

 closely spaced when planted (4,500-5,000 plants per hectare) but 

 that the thinnings be so made that the trees chosen for the final 

 stand have a wide spacing. A. B. R. 



Mitteilungen aus dem forstlichen Versuchswesen Oesterretchs. Allgemeine 

 Forst- und Jagd-Zeitung, May, 1915, pp. 122-5. 



An investigation was started at the Royal 



Lime Agricultural College, Circencester, in 1914, 



Effect by Hopkinson and Elkington, the object of 



on which was to ascertain the effect of varying 



Growth quantities of calcium carbonate on the 



growth and development of certain conifers. 



Douglas fir (Pseudotsuga donglasii Carr) was the species selected, 



since it is supposed to be calcifuge. Two-year seedlings were 



