1052 EXPERIMENT STATION RECORD. 



regarding the source, nature, and use of fertilizers, giving also suggestions regarding 

 the mixing of fertilizers and a discussion of methods of valuation. 



The fertilizer industry ( Tradesman, 54 {1906), No. 9, pp. 98, 99). — Data are 

 given for 10 southern States, showing 162 fertilizer establishments with an invested 

 capital of *29,966,685 and a value of product of $18,921,591. 



Mineral resources of the United States, calendar year 1904, D. T. Day 

 ( U. S. Geol. Survey, 1905, pp. 1264, pis. 2). — The principal information of agricul- 

 tural interest in this report has already been noted from another source (E. S. R., 

 17, p. 451). 



Fertilizer trials at the Royal Agricultural Academy of Sweden, 1903-4, 

 H. G. Soderbaum (K. Landtbr. Akad. Handl. och Tidskr., 44 (1905), No. 4-5, pp. 

 289-311, fig. 1). — On the after effects of different kinds of phosphatic fertilizers. — This is a 

 report of an investigation conducted since 1901, in which the effects of the following 

 phosphatic materials have been studied: Superphosphate, dicalcium phosphate, tri- 

 calcium phosphate, precipitated phosphate, and bone meal. Different varieties of 

 oats were grown in vegetation pots each year, and after the first year applications 

 of sodium nitrate and potassium sulphate, with or without addition of calcium 

 carbonate, were made each year. 



The highest aggregate yields of oats for the four-year series were obtained from the 

 applications of superphosphate and of dicalcium phosphate, and the action of these 

 fertilizers appeared to be independent of whether or not lime had been added. The 

 effect of both tricalcium phosphate and bone meal was reduced by nearly one-half 

 during the four years by the addition of lime, and the superiority of the former over 

 the latter in the case of the limed pots, and of bone meal over the tricalcium phos- 

 phate in the case of the pots receiving no lime, gradually disappeared, so that the 

 total results for the entire series were practically the same. The action of bone meal 

 (with no lime) was found to be decidedly inferior to superphosphate even after the 

 fourth year. 



The fertilizer value of Algerian phosphate and apatite compared with that of other phos- 

 phatic materials. — The trials were made in 10-in. glass cylinders, with oats grown in 

 a sandy soil, and with peas grown in a marsh soil. In the former trials Algerian 

 phosphate produced an increase of only 3.3 to 5.3 per cent over the cylinders receiv- 

 ing no phosphoric acid, the increase obtained in the case of superphosphate being 

 placed at 100, and the increase in the case of the fine-ground apatite amounted to 

 0.4 to 1 per cent, according to the quantity of phosphoric acid added (50 to 150 kg. 

 per hectare). In the latter trials with peas on marsh soil the effect of the sifted 

 Algerian phosphate w T as about 57 per cent of that of superphosphate for peas alone, 

 and 63.7 per cent for the entire crop (peas and vines). The corresponding figures 

 obtained for apatite were 3.9 per cent and —1.4 per cent. 



Culture trials to determine in how far the effect of phosphatic fertilizers depends on the 

 character of the simultaneous nitrogenous fertilization. — it has been .found in earlier 

 investigations that the effect of superphosphate or dicalcium phosphate was not 

 influenced by the kinds of nitrogenous fertilizer applied, but that the tricalcium 

 phosphate and bone meal produced appreciably larger crops when mixed nitrogenous 

 fertilizers were applied than when sodium nitrate only was added with the 

 phosphates. 



This subject was studied further by the author during the years 1902 to 1904. In 

 pot experiments with Ligowo oats, in which different phosphatic materials were 

 added with either nitrate of soda or nitrate of ammonia, the results obtained with 

 superphosphate or Thomas phosphate were higher in the case of applications of 

 nitrate of soda than when corresponding amounts of ammonium nitrate were applied, 

 while the opposite held true with Algerian phosphate and with bone meal. The 

 effect of applications of different nitrogenous fertilizers in connection with bone meal 



