SOILS — FERTILIZERS. 625 



The general results of two series of experiments comparing different phos- 

 phates, one oxtonding over twelve and the other over eighteen years, are pre- 

 sented to show that the application of at least a moderate amount of phospliate 

 is usually profitable and that the more soluble and available materials give re- 

 sults nuich superior to those obtained with the fine ground rock phosphates. The 

 more solul)le phosphates were found to favor more rapid early growth, earlier 

 and more perfect maturity, and larger yields than the rock phosphates and 

 to be used with greater profit. 



On this basis Massachusetts farmers, gardeners, and orchardists are ad- 

 vi.sed against the general use of raw rock phosphates. "The phosphates em- 

 ployed should be the more soluble and available kinds, such as acid phosphate 

 (dissolved rock), dissolved bone, basic slag meal, and bone meals." 



Phosphoric acid and potash fertilization in the spring', Schneidewind 

 (Landw. Wchnschr. Snchscn, 17 {1915), No. 8, pp. 61, 62). — Seven years' 

 fertilizer experiments witli potatoes and sugar beets, and with wheat and barley 

 as second crops, with and without stable manure fertilization, are summarized 

 to show that these crops, when growing on soil fertilized with stable manure, 

 either need no additional phosphoric acid or much less than is needed when no 

 stable manure is used. Also the after effects of stable manure fertilization 

 are considerable, as is indicated by the superior yields and smaller additional 

 phosphoric acid requirements of wheat and barley as second crops on soil 

 fertilized with stable manure. 



A general statement is included as to the foixus of phosphoric acid and 

 potash best adapted to different soils. 



Potash salts, 1914, W. C. Phalen (U. 8. Geol. Survey, Mineral Resources of 

 the United States, Calendar Year 1914, pt. 2, pp. 9-33, pi. 1; Press Bui. 215 

 (1915), p. 4). — This report gives statistics of potash salts and of materials 

 entering into the fertilizer industry imported for consumption in the United 

 States during 1914 and several preceding years, discusses briefly the work done 

 in 1914 with a view to finding a domestic supply of potash, and gives data 

 regarding foreign potash deposits, particularly those of Spain (E. S. R., 33, 

 p. 26). 



It is stated that the potash salts imported for consumption in the United 

 States in 1914 was 485,818,459 lbs., valued at $8,743,973, a decrease in quantity 

 and value as compared with 1913 of 126,696,457 lbs. and $2,061,747, respectively, 

 No especially notable developments in the discovery of new sources of potash 

 with the object of establishing a domestic potash industry are reported. 



In addition to potash salts, bone dust, calcium cyanamid, guano, basic slag, 

 and other materials used as fertilizer, including kainit and manure salts, were 

 imported in 1914 to the extent of 761,896 long tons, valued at $9,921,439, and 

 sodium nitrate valued at $15,204,539. 



A bibliography of papers on potash salts appearing during 1914 is given. 



Radium fertilizer in field tests, C. G. Hopkins and "W. H. Sachs (Science, 

 n. ser., 41 (1915), No. 1063, pp. 732-735) .—This is a brief article based mainly 

 upon experiments reported in more detail elsewhere (E. S. R., 32, p. 821), 

 calling attention to the fact that the amount of radium which can be applied 

 even at a cost of $100 per acre is so small that it does not and can hardly be 

 expected to produce any effect upon crop yields. 



A municipal fertilizer plant at Los Angeles, California, B. A. Heinlt 

 (Engin. News, 73 (1915), No. 22, pp. 1063, 1064).— Three plants built and 

 operated by the park department of Los Angeles for the production of manure 

 compost are described. 



