Periodical Literature 509 



SOIL, WATER AND CLIMATE 



A highly interesting series of detemiina- 



Muskeg tions of mineral constituents in an artificially 



Soil forested peat soil is reported by Ramann and 



and Niklas, of the Soils Division of the Bavarian 



Tree Growth Experiment Station, which gives an insight 



into the character of such soils and silvi- 



cultural possibilities of the same. 



At the Moor Culture Station Bernau, Dr. Ebermayer, in 1896 

 to 1898, planted or sowed, with application of various fertilizers, 

 spruce, birch and other conifer and deciduous species. 



The sowed birch stand grew thriftily into a thicket, until 10 

 years, when the height growth ceased and the crowns rounded off. 

 A thinning revived the height growth. Then, in order to find out 

 the influence of thinnings on mineral constituents, the present 

 investigation was inaugurated by laying in a severe thinning in 

 half the area, leaving the other half untouched. 



Since moor soils are independent as to water, but relatively 

 poorly supplied as to mineral constituents, they furnish good 

 objects for such investigation of the relation of minerals to tree 

 growth. In such soils, the minerals are either highly fixed, so 

 that they cannot be taken up by the roots, or else, like the alkali 

 easily soluble. By extracting the entire salt contents with a 

 Kohlrausch apparatus and measuring the electric resistance of this 

 extract, the presence of soluble salts can be readily determined. 

 Thirty sample spots 5 to 10 w apart were analyzed in this way, 

 besides 10 spots were investigated for the imderground. The 

 samples were taken at 5 to 20 cm depth in the surface soil and 40 to 

 60 cm in the underground. The analyses were repeated in 1911 

 and 1912, and are tabulated. Ftuther details of the procedure 

 are given. 



From the resvilts apparently one might conclude that the con- 

 tents of soluble salts was higher on the thinned area, and only 

 in the autumn after leaf fall somewhat lower than on the un- 

 thinned. The authors, however, caution against this conclusion, 

 since the variations in the single analyses lies within very wide 

 limits. But the possibility of this highly important influence of 

 thinning is indicated. 



Very close, however, is the relation between salt contents of 

 the soil and the development phases of tree life, especially the leaf 



