656 EXPERIMENT STATION RECORD. 



cent. There was no appreciable after-effect from applications of the lime nitrogen. 

 The growth of the plants was apparently somewhat retarded by applying the lime 

 nitrogen as a top-dressing. 



Liming, A.Oktii (Atb. Deut. Landw. Gesell., 1904, No. 98, pp. 79-90). — A general 

 discussion. 



Nitrate of soda (Engin. and Min. Jour., 79 (1905), No. 1, p. 64). — The American 

 consumption of nitrate of soda in 1904 is reported as 275,000 long tons; the European 

 consumption was 1,105,000 tons; the local consumption (in Chile and neighboring 

 countries) 28,000 tons. 



Nitrate profits {Engin. and Min. Jour., 79 (1905), No. 3, p. 130).— The world's 

 consumption of nitrate of soda is stated in this article to be about 1,450,000 longtons, 

 containing 1,349,100 tons of nitrogen. The cost to consumers during 1904 was from 

 $40 to $48 per ton, which is about $10 more per ton than in 1903. The possibilities 

 of a further rise in price are discussed. 



The action of nitrate of soda as a potassic and calcareous fertilizer, T. 

 Biei.kk (Chron. Agr. Canton Vaud, 17 (1904), Nos. 11, />/>. 332-335; 12, pp. 353-362; 

 13, pp. 3S3-390; l/ f , pp. 409-417; 16, pp. 462-475; 17, pp. 508-517) .—The author 

 reviews the work of various investigators in so far as it bears on the question of the 

 action of nitrate of soda in rendering plant food soluble in soils. 



The observations noted apply to sandy clay soils, and lead to the conclusion that 

 nitrate of soda exerts a fertilizing effect independent of the direct supply of plant 

 food which it supplies, in rendering the potash and lime of the soil soluble, and 

 thus acts as an indirect potash and lime fertilizer. In soils containing small amounts 

 of lime nitrate of soda renders potash soluble more completely than superphosphates, 

 sulphate of ammonia, gypsum, etc., and to a greater depth, because (a) the nitrate 

 of potash formed moves more freely in the soil than other potash salts, and (b) the 

 calcium nitrate formed also moves freely through the soil and assists in the mobiliza- 

 tion of the potash. 



To this extent nitrate of soda may be considered an indirect potassic fertilizer. It 

 may also be so considered because it renders assimilable soil potash which is insoluble 

 in acids by the ordinary treatment. 



It is also to be noted that commercial nitrate of soda often contains an appreciable 

 amount of potash and the effect sometimes attributed to the soda may, in fact, be due 

 to this potash. On soils rich in potash potassic fertilizers may be entirely dispensed 

 with when nitrates in connection with phosphates are used, especially in case of 

 hoed crops. 



In any case potash fertilizers may be economized by the use of nitrates (either of 

 soda or of lime) or by promoting nitrification in the soil. Nitrate of soda, like the 

 sulphates of potash and ammonia and chlorid of potash, acts as an indirect lime fer- 

 tilizer by mobilizing the lime in the soil. 



Unless the soil is very rich in lime, liming should accompany the use of these 

 substances. 



Action of calcium compounds on the mobilization of potash in soils, 

 J. Dumont (Bui. Soc. Nat. Agr. France, 64 (1904), No. 5, pp. 379-384).— The solvent 

 effect of quicklime, calcium carbonate, gypsum, calcium chlorid and nitrate, and 

 monocalcium phosphate on the potash of different soils and different grades of soil 

 particles was studied in laboratory experiments. 



The results reported show that when a granitic soil was mixed with gypsum and 

 calcium chlorid at rates furnishing 10 per cent of lime (CaO) and moistened, the 

 gypsum rendered soluble 0.048 part of potash per 1,000 of soil in 28 hours, 0.073 part 

 in 10 days, and 0.096 part in 4 months. The calcium chlorid rendered 0.115 part of 

 potash soluble in 28 hours, and there was no increase by further treatment. The 

 comparative results obtained in a one month's experiment were as follows: 



