SOILS FERTILIZERS. 925 



With ODe exception the soils wLiicIi were benefited by applications of phos- 

 phates showed low percentages of phosphoric acid soluble in fifth-normal nitric 

 acid. In all of the trials with the one exception referred to soils which con- 

 tained over 150 parts per million of phosphoric acid soluble in fifth-normal 

 nitric acid were not benefited by application of pLosphatic fertilizers. 



The soil showing the smallest amount of potash soluble in fifth-normal nitric 

 acid gave the largest increase when potash fertilizer was added, while that con- 

 taining the largest amount of soluble potash gave no increase with potash fer- 

 tilizer. The chemical tests showed a deficiency of phosphates more distinctly 

 than a deficiency of potash. 



Peas as a fertilizer in the Northwest, F. T, Shutt (Canada Expt. Farms 

 Rpts. W06, pp. 155-158). — This is a brief general discussion of the value of 

 peas as a substitute for clover for soil improvement in this region. Data are 

 given which show that crops of peas can be grown supplying 130 lbs. of nitro- 

 gen per aci-e, which is practically identical with that produced by alfalfa, 

 vetches, and many of the clovers. The organic matter produced is equal in 

 quantity to that yielded by a good clover crop, though somewhat less than that 

 produced by alfalfa. The pea crop shows large percentages of phosphoric acid 

 and potash, particularly the latter. 



Experiments with nitrate of soda, ammonium salts, and lime nitrogen as 

 fertilizers, P. Wagner, G. Hamann, and A. Mxjnzinger (Arb. Deut. Landw. 

 GescU., 1907, Xo. 120, pp. VI+286; abs. m Mark Lane Express, 97 (1907), 

 No. 3975, p. 677; Mitt. Dcut. Laiidiv. Gesell, 22 (1907), No. .'i2, pp. 36'f-366).— 

 This is a report of a continuation of cooperative experiments which have been 

 carried out since 1901 under the auspices of the German Agricultural Society by 

 the Wagner or Darmstadt method of field experimenting (E. S. R., 15, p. 234; 

 18, p. 621). The detailed data are given of 34 experiments of from 1 to 7 years' 

 duration at 12 different places with oats, barley, wheat, beets, and potatoes, 

 together with a summary of the results of these and similar experiments. 



Wagner concluded from a large number of pot experiments that ammonium 

 salts have 94 per cent of the fertilizing efficiency of sodium nitrate. In field 

 experiments a much lower efficiency for the ammonium salts was indicated, 

 better results being obtained with grains than with beets. For the production 

 of grain ammonium sulphate was 75 per cent as efficient as nitrate of soda, for 

 production of beets 68 per cent. As a general result of all the field experiments 

 the practical fertilizing efficiency of ammonium sulphate in field culture is 

 placed at 75 per cent of that of nitrate of soda. The possible causes of the 

 lower efficiency of ammonium salts, namely, escape of ammonia into the air, 

 transformation of the ammonia into organic substances, and a very strong 

 fixation of nitrogen in clay soil, are discussed as in previous reports (E. S. R., 

 18, p. 621). 



In case of grain 34.1 lbs. of nitrate nitrogen was equal to 45.54 lbs. of nitro- 

 gen in ammonium sulphate. The relationship in case of beets was not so clearly 

 indicated. There was a very slight difference in the ratio between grain, or 

 roots, and straw, or leaves, under the influence of the different fertilizers. 

 Heavy manuring with the nitrogenous fertilizers always resulted in an increase 

 in the proportion of straw or leaves as compared with grain or roots, the in- 

 creases being greater in all cases with nitrate than with the other nitrogenous 

 fertilizers. The differences, however, are considered too small to be of any 

 practical importance. The application of the nitrogenous fertilizers in every 

 case slightly increased the nitrogen content of the grain or roots, but decreased 

 that of the straw and leaves. The differences are too small to be of practical 

 importance, and other factors, such as soil, weather, variety, etc., seem to have 

 much greater influence than the fertilizing. It is estimated that the soils used 



