SOILS FERTILIZERS. 725 



The results of hoih analysis and vegetative experiments agreed in showing 

 that acid soils contained smaller amonnts of available nitrogen and phosphoric 

 acid and usnally lower percentages of potash than neutral or alkaline soils. 

 As a rule, also, yields were lowest on acid soils and highest on neutral and 

 alkaline soils. 



Potash in clay and granitic soils, J. Babcia y Tkelles {Prog. Agr. y Pecua- 

 rio, n {1911), Xos. 727, pp. 3-^9-351; 728, pp. 365, 366; 729, pp. 382, 383).— This 

 article emphasizes the fact that, although determinations of potash may in some 

 cases furnish valuable indications of the potash requirements of soils, analysis 

 is not an infallible guide and should be supplemented by field exi>eriments. It 

 is shown that many soils derived from granites and rich in potash are benefited 

 by potash fertilizers. 



Investigations on the action of different proportions of lime and magnesia 

 in some soils on higher plants and micro-organisms, O. Lemmermann, 

 A. EiNECKE, and H. Fischer {Landw. Jahrb., 40 {1911), No. 1-2, pp. 173-254; 

 ahs. in Chem. ZcntbL, 1911, I, No. 25, pp. 1760, 1761 ; Zt.schr. Angew. Chem., 24 

 {1911), No. 25, pp. 1187, 118S; Jour. 8oc. Chem. Indus., 30 {1911), No. 13, p. 821; 

 Chem. Al)-s., 5 {1911), No. 19, p. 3314). — The authors report the results of 

 a large number of experiments conducted during 1907, 1908, and 1909 on 6 soil 

 types and with 8 different crops, to determine the action of different propor- 

 tions of lime and magnesia on plants and soil organisms (bacteria). 



It was found that as far as the yield was concerned variations within wide 

 limits in the proportion of lime to magnesia had no effect. It was not possible 

 to increase the yields by maintaining definite proportions of lime to magnesia. 



Plants varied in their behavior toward lime and magnesia. Even soils con- 

 taining only 0.08 per cent lime and 0.04 per cent magnesia, or, 0.067 per cent 

 lime and 0.09 per cent magnesia, gave no increase in yield with many plants 

 from applications of lime and magnesia. It seems necessary, therefoi-e, that in 

 order to draw correct conclusions the same plants must be studied for several 

 consecutive years on the same soil. 



The favorable action of lime on the mustard plant was not dependent alone 

 upon the nutritive value of lime, but also upon other factors. 



The lime content of grain was much less than that of straw. Grain and 

 straw varied less in magnesia than in lime. Grain contained more magnesia 

 than lime, whereas the straw contained more lime than magnesia. 



Variable amounts of lime and magnesia applied to, as well as contained in, 

 the soil influenced more distinctly the composition of the straw than that of 

 (he grain. 



The lime, magnesia, and phosphoric acid content of plants may vary greatly 

 for substantially the same yields. 



The lime-magnesia fertilizers influenced also the utilization of phosphoric 

 acid in that a high magnesia and a low lime content of fertilizer decreased the 

 lime content of the crop, whereas that of the phosphoric acid and magnesia 

 increased. 



The varying solubility and absorption of lime and magnesia fertilizers must 

 be considered in the determination of the exact relation of lime and magnesia 

 in the soil. 



As with the higher plants, no distinct relation of lime to magnesia could be 

 established as particularly favorable to soil bacteria. 



The authors believe that the study of the optimum proportion of all plant 

 nutrients to each oth^r is an important work of the future. 



Investigations on the lime requirements of cultivated soils, O. Lemmer- 

 MAx\N, O. FoEKSTJiR, aud A. Einecke {Landw. Jahrh., 40 {1911), No. 1-2, pp. 

 14867°— No. 8—11 3 



