1916] SOILS FERTIUZEBS. 323 



the formation of substances which the plant takes from the soil and utilizes in 

 building up its tissue. 



Manuxial experiments, G. K. Kelkab (Dept. Agr. Bombay, Ann. Rpt. Expt. 

 Work Surat Agr. Sta., 1913-14, pp. 23-31). — Six years' fertilizer experiments 

 with cotton and sorghum are summarized, the results of which are taken to 

 indicate that barnyard manure may well be replaced by rotted cactus, poudrette, 

 tank mud, town sweepings, and mowra refuse. 



Experiments with cotton and sorghum on the residual effect of night soil 

 showed that ten years after application superior results were still obtained. 

 Experiments conducted since 1911 comparing the fertilizing value of night soil 

 and poudrette for cotton and sorghum gave results generally in favor of the 

 night soil. Experiments conducted since 1908 to compare the fertilizing values 

 of sodium nitrate, calcium nitrate, ammonium sulphate, calcium cyanamid, and 

 barnyard manure, Avhen applied to cotton and sorghum at the rate of 10 lbs. 

 of nitrogen per acre, showed that for cotton sodium nitrate and calcium nitrate 

 gave the best results, while for sorghum ammonium sulphate and the other 

 artificial fertilizers gave as good results as sodium nitrate. 



Experiments with cotton comparing the fertilizing value of a combination of 

 80 lbs. of calcium nitrate and 160 lbs. of superphosphate per acre, with and 

 without 2.4 tons of barnyard manure per acre, and with barnyard manure 

 alone applied at the rate of 8 tons per acre, showed that the best results were 

 obtained with the combination of artificial fertilizers without manure. The 

 results with manure alone and with manure and the artificial mixture were 

 approximately equal. 



Experiments with cotton and sorghum showed that neither of these crops 

 responded to nitrogenous, phosphatic, or potash fertilization on black cotton 

 soil. Experiments with cotton and sorghum comparing barnyard manure alone, 

 used at the rate of 3 tons per acre, and a combination of 60 lbs. of ammonium 

 sulphate, 224 lbs. of superphosphate, and 1..5 tons of manure per acre with and 

 without 80 lbs. of potassium chlorid per acre, showed that the best results were 

 obtained with cotton with the mixture without potash. The difference in 

 results obtained with the mixture with potash and with manure alone was 

 slight. 



Report on field fertilizer experiments at the Bernau moor cultivation sta- 

 tion, A. Baumann and H. Paul (Mitt. Deut. Landw. Gesell., 30 (1915), Nos. 42, 

 pp. 627-630; 43, pp. 651-653; 45, pp. 686-688) .—The classified results of four 

 years' experiments with nitrogenous, phosphatic, and potash fertilizers, stable 

 manure, green manure, and lime on an upland moor soil deficient in both 

 nutritive constituents and lime are reported. The cropping system consisted of 

 potatoes, followed ijn the third or fourth year by rye, which was then followed 

 by meadow or pasture. 



A half-and-half mixture of 40 per cent potash salt and potassium-magnesium 

 sulphate was the best potash fertilizer used, giving even better resutls than the 

 40 per cent potash salt alone. Phonolite meal was unsuitable as a potash fer- 

 tilizer for this soil. Wolters sodium phosphate gave on the average the best 

 results of the phosphates used, being better than bone precipitate. Of the 

 nitrogenous fertilizers used, sodium nitrate gave the best results, followed in 

 order by calcium nitrate, lime nitrogen, and ammonium sulphate. Of these, 

 ammonium sulphate produced the greatest increase in the starch content of 

 potatoes. 



Stable manure used at rates of 300 and 400 kg. per hectare (267 and 356 lbs. 

 per acre) produced greater crop increases than smaller applications of 200 to 

 300 kg. per hectare. The increases were small, however, as compared to those 

 56493°— 16 3 



