1919] 



SOILS — FERTILIZERS. 723 



carbonate, and Iron nitrate, in some of the concentration* tested, acted as 

 stimulants, the extent <>t' the stimulation and quantity of salt necessary for 

 maximum stimulation varying with the specific compound. " Naming them in 

 the order of Increasing efficiency, they are: Sodium nitrate, magnesium sul- 

 phate, ferric sulphate, calcium nitrate, potassium nitrate, potassium chlorid, 

 magnesium nitrate, manganoua carbonate, manganous chlorid, manganous sul- 

 phate, iiiric carbonate, magnesium chlorid, manganous nitrate, ferric chlorid, 

 magnesium carbonate, sodium chlorid, calcium chlorid, and calcium sulphate. 

 The las! two Increased the nitric-nitrogen accumulation of the soil <'>" and 97 

 per cent, respectively. Those compounds which are the strongest plant stimu- 

 lants arc also the most active in increasing the nitric-nitrogen accumulation of 

 the soil. . . . Many of the nitrates caused large losses of nitric nitrogen 

 from the soil; this is due to the stimulation of other spedes which transform 

 the nitric nitrogen Into protein nitrogen and not to denitrification. liagnesium 

 nil rate, ferric nil ride, calcium nitrate, and manganous nitrate are very active 

 stimulants of the nitrogen-nxtng organisms. In some cases these compounds 

 Increased nitrogen fixation many times over that in the normal soil." 



In general 11 is concluded that "the ammonifying powers of a soil containing 

 alkalis are a better index of its crop-producing powers than are the nitrifying 

 powers." 



A list of references to literature cited is given. 



Stable manure and nitrification in the soil, C. BEBTHEI and N. Bkngtsson 

 (A', fjni'lthr. Akad. Handl OCh Tidskr., 57 (1918), pp. 353-367; abs. in Chcm, 

 M'.t., 13 (1919), No. 5, pp. ^90). — In the experiments here reported, it was 

 found that calcium carbonate in ordinary amounts appeared to have no influ- 

 ence upon nitrification. Applied in amounts much larger than are used in 

 practice, it exerted an inhibitive Influence. 



Decomposition and preservation of liquid manure, E. Bt.anck (LahdtO. 

 Yds. Shit., 91 (t918), pp. 25.) ..'<;.''. 871 890, S09-3J f 3; ah*, in Jour. Soc. Chcm. 

 Indus., .17 (1918), No. 17. p. 522 A; Chcm. Abs., 13 (1919), No. 1, p. 53).— It was 

 found in the experiments here reported that the treatment of liquid manure 

 with sulphuric acid prevented loss of nitrogen by fixation up to a certain limit 

 of the ammonia formed. Formaldehyde preserved the liquid manure, but its 

 use is not recommended because of its injurious effect on plant growth. 



Fertilizer experiments on DeKalb soil. Yields of clover, corn, and Ken- 

 tucky blue grass, J. \v. Wiirrt: (Pennsylvania Bta. Bui: 155 (1919), pp. 3-20, 

 figs. 8). — Continuing work previously noted (B. S. It., 39, p. 22), this bulletin 

 presents the results obtained during 1918 with corn and Kentucky blue grass 

 on DeKalb soil under various fertilizer treatments. Results obtained in 1917 

 and with clover hay tire included for purpose of comparison. 



Based on the net value per acre of corn and stover, the greatest return in 

 the fertilizer and manure experiment, $56.16, was secured from the plat 

 receiving limestone, acid phosphate, and potash, followed by that receiving lime- 

 stone, acid phosphate, and manure with a return of $53.36, and tin; limestone 

 and complete fertilizer plat with $51.40. Manure reinforced with 45 lbs. of 

 phosphoric acid in acid phosphate produced a net return of $13.53 in excess of 

 that reinforced with 180 lbs. of phosphoric add in rock phosphate. In the 

 phosphoric-acid series the increased yields and value of the corn crop was In 

 the order of increased applications of acid phosphate, the highest net return, 

 $51.28, following the use of limestone and GOO lbs. of acid phosphate. The 

 same amount of acid phosphate used with limestone, nitrogen, and potash pro- 

 duced a net return of $49.99. 



