SOILS FERTILIZERS. 1015 



A sliakins uiacliine for use in eoniioctioii with Dyer's nietboil of soil analysis 

 is des('ril)e(l. and the need and main ro(inirenu'nts of a general soil snrve.t are 

 discussed. 



Investigations on chernozem (black soil) from Southwest Russia, and its 

 plant food requirements, A. von Uhiumov (Mitt. Laiulw. Inst. Leipzig, 1D07, 

 No. S, pp. 3-67, pis. 3, fiy.s. 3). — This article discusses briefly theories of the 

 origin and formation of chernozem soils, describes the physicjgraphic features 

 and structural characteristics of the particular soil studied in this case, and 

 reports mechanical and chemical analyses of the soil and pot and field experi- 

 ments to determine its fertilizer requirements. The methods used in the 

 analysis of the soils, fertilizers, and plant products are briefly described. 



The mechanical analyses reported show from 52 to G3 per cent of material 

 removed by elutriation and no particles larger than 2 to 3 mm. diameter. Not- 

 withstanding the fact that the soil was very fine-grained, it had a granular 

 structure very favorable to percolation and similar processes. 



The chemical analysis of the soil showed potash 0.2 per cent, lime 0.57 per 

 cent, nitrogen 0.23 per cent, and phosphoric acid 0.03 per cent, indicating that 

 the soil is especially poor in phosphoric acid. Examination by means of Bog- 

 danov's method (shaking 1 kg. of soil in 4 liters of 2 per cent acetic acid for 

 48 hours) showed only 0.00073 per cent of phosphoric acid, indicating a great 

 deficiency of assimilable phosphoric acid. 



Pot and field experiments with wheat and analyses of the crop produced bear 

 out the chemical analysis in indicating that phosphoric acid is the element of 

 plant food especially needed in this soil. The field experiments indicated that 

 superphosphate might be used at the rate of 26.7 lbs. of phosphoric acid per acre 

 with iirofit. 



Variations in steppe soils in different climates, F. Gessert (Natiinv. 

 Wcluischr., 22 (1907), No. 7/5, pp. 705-707). — This is a brief general discussion 

 of the origin, formation, and characteristics of steppe soils in different parts 

 of the world. 



A distinction is drawn in this discussion betvA'eeu the steppe soils of tropical, 

 subtropical, and temperate zones, but particularly between steppes of cold 

 regions and those of warm regions. For example, those of South Sahara, con- 

 sisting mainly of shifting sands deficient in humus, are compared with those 

 of eastern Russia and Siberia, which are held in place by more or less vegeta- 

 tion and contain considerable amounts of humus. 



The transportation of soil particles from one steppe region to another — as, 

 for example, from the Sahara into the Chinese loess region — is explained by 

 the variation in atmospheric pressure over the different areas, resulting in 

 strong air currents from one to the other. 



Soils [of British East Africa] (Bui. Imp. Inst., r> [1007), No. 3, pp. 2>,3- 

 2fi6). — Mechanical and chemical analyses of 3 samples of typical soils are re- 

 ported and discussed. The soils contained a large proi)ortion of clay and when 

 mixed with a small quantity of water formed a stiff plastic mass. They were 

 fairly w^ell sui)plied with nitrogen and iwtash, but were deficient in phosphoric 

 acid, a deficiency which is stated to be conunon throughout East Africa. 



The conservation of soil moisture, F. F. Matenakrs {Fiihling's Lanilw. Ztg., 

 56 {1907), No. 21, pp. 75//-756, fig. 1). — The cultural methods employed in the 

 arid jiortion of the Ignited States for conserving the soil moisture are described. 



The productiveness of the soil, A. GitliGoiHE {But. Soc. Cent. Forest. Bclg.. 

 1.1, (1907). No. 7. pp. 3H0-.V)7, figs. 2; Ann. Ccmhtonx. /N (WOS). No. 1. pp. 2,S- 

 ■'iS, figs. 2). — From a review of the literature bearing on this subject the follow- 



