724 EXPERIMENT STATION RECORD. [Vol.35 



bacteria nor nitrate bacteria liberate appreciable amounts of soluble phosphorus 

 from insoluble phosphates." 



It is pointed out that " plants are important factors in the liberation of 

 phosphorus, owing to the production of carbon dioxid and the removal of the 

 soluble phosphorus produced by the bacteria. . . . Other acid-producing bac- 

 teria make phosphorus soluble from insoluble phosphates according to the 

 nature and amount of the acid produced. A comparison of the amounts of nitro- 

 gen, phosphorus, and calcium required by farm crops, with those possible of 

 solution by biochemical action, shows possibilities far beyond the plant require- 

 ments, which leads to the conclusion that plenty of rock phosphate in contact 

 with decaying organic matter must give the plants an excellent opportunity to 

 obtain both phosphorus and calcium as well as nitrogen." 



Disinfection experiments on moor soil, A. von Nostitz (Landw. Jahrb., ^S 

 (1915), No. 4, pp. 587-606, pi. 1, figs. 3; abs. in Ztschr. Angew. Chem., 29 {1916), 

 No. 16, Refer atenteU, p. 98; Chem. Zentbl., 1916, I, No. 3, p. 115). — Experiments 

 with upland moor soils on the influence of carbolineum, calcium chlorid, and 

 potassium permanganate when used as soil disinfectants are reported. Carbo- 

 lineum was found to give better results than calcium chlorid. 



The use of the disinfectants was accompanied by marked increases in crop 

 yield, especially in the case of carbolineum. Carbolineum gave better results the 

 earlier it was used before seeding and gave the best results when used at the rate 

 of from 50 to 60 gm. per square meter of soil. Carbolineum rich in volatile con- 

 stituents was more effective than when poor in these constituents. The action 

 of carbolineum was especially marked with reference to its influence on the bac- 

 teria and nematode contents of soil. 



Niter spots, W. Staldee {Science, n. ser., IfS {1916), No. 1116, pp. 712, 713).— 

 The author refers to the theories of Sackett and of Stewart and Peterson 

 regarding the origin of brown niter spots in arid soils (E. S. R., 25, p. 815; 33, 

 p. 121), and reports his observations on niter spots in northwestern Nevada, 

 which showed that the feces of jack rabbits when coming in contact with alkali 

 water or moist alkali soil decomposed comparatively rapidly, forming brown 

 spots containing nitrates. It is concluded " that the brown niter spots of the 

 playas were, as far as examined, of animal origin. From these observations it 

 is safe to predict that in fields of the arid western States brown niter spots will 

 appear when live stock is pastured in the same and alkaline waters are used for 

 irrigation." 



Acid phosphate versus raw rock phosphate as fertilizer, A. T. Wiancko and 

 S. D. CoNNEB {Indiana Sta. Bui. 187 {1916), pp. 1055-1082 fig. i).— This bulletin 

 reports the results of 82 comparative tests of acid phosphate and raw rock phos- 

 phate which have been made by the Indiana Station since 1904. Series of tests 

 covering varying lengths of time, but an average of 3.47 years, are reported, 

 which " are believed to give a fair comparison of the use of the two phosphates 

 under average Indiana field conditions with various crops and during different 

 seasons on a large number of soil types." The crops grown included rotations of 

 corn, wheat, and clover or soy beans, and potatoes and soy beans. The applica- 

 tions of acid phosphate varied from 150 to 500 lbs. per acre, averaging 205 lbs. 

 and were valued at $16 per ton ; of the rock phosphate from 350 lbs. to 1 ton, 

 averaging 545 lbs. and valued at $7.50 per ton. The phosphates were used alone 

 and combined with manure and were supplemented by applications of limestone 

 when liming of the soil was deemed necessary. 



The results are summarized in the following table: 



