322 EXPERIMENT STATTON EECORD. 



periment with radishes by the pot and water-culture methods of the Bureau 

 of Soils of this Department, the plants being grown for 15 to 19 days In solu- 

 tions or 24 to 32 days In soils containing varying proportions of potash, soda, 

 and other constituents, biit of equal concentration, and then being transferred 

 for 2 or 3 days' growth in a full nutrient solution. It was observed that the 

 general development of the plants was in the same relative order as their 

 transpiration. The presence of sodium increased the transpiration and size 

 of plants ex'en when there was an abundance of potash and other mineral con- 

 stituents in the solution. As a rule, however, the effect of soda in increasing 

 the size of the plant was not marked where no potash was present. 



In case of both soil and solution cultures " there was a greater demand for 

 potassium in the plants wliidi had been growing in a [medium] which had 

 received no potassium than in the plants which had always had a suflicient 

 quantity of that element. . . . The absorption of potassium from the solution 

 of the second period was strikingly decreased when sodium was present in the 

 solution of the first period. . . . Plants which for the first period grew in a 

 solution containing sodium liut no potassium drew less heavily upon the potas- 

 sium of the full nutrient solution than the plants which for the first period 

 grew in a solution containing neither sodium nor potassium. There was a 

 greater absorption of potassium where sodium had been absent than where it 

 had Iteen present." 



The deficiency of potash resulting from systems of fertilization in Bel- 

 gium, Vekstraete {Bui. Soc. Chim. Belg., 19 {1905), A'o. 8-9, p. 267). — Figures 

 are presented to show that the systems of fertilization practiced during many 

 years past in Belgium have resulted in a decline in total and available potash. 



The loss of nitrogen from soils in fertilizing with nitrate of soda, J. 

 Stoklasa, J. .Jelinek, and A. Ernest (Zfschr. Zuchcriudus. Bohmcn, 30 {1906). 

 No. 5, pp. 223-233; ahs. in Chem. CentU., 1906, I, No. 11,, pp. IISI, 1182; Jour. 

 Chcm. Soc. [London]. 90 {1906), No. 523, II, p. 303).— Culture tests in Gil- 

 tay-Aberson solutions with various samples of soils rich in humus and of 

 Bohemian sugar-beet soils are reported, which show that when glucose and salts 

 of citric acid were present there was a considerable loss of nitrogen by deni- 

 trificatlon. Other experiments with extracts of the soils inoculated with Bac- 

 terium, hartlebi indicated that the soils were deficient in organic substances 

 which could serve as a source of carbon for denitrifying organisms. The 

 authors therefore conclude that with proper tillage these soils would not lose 

 nitrogen in the free state. 



The natural losses of nitrogen from soil and the use of nitrate of soda, 

 L. Grandeau {Jour. Agr. Prat., n. ser., 11 {1906), No. 18. pp. 553, 55Jf). — A brief 

 discussion of this subject based upon investigations made at Rothamsted 

 (E. S. R.. 17, p. 533). 



Nitrification as studied by means of drainage water, J. Hudig {Cultura, 

 18 {1906). No. 211. pp. l.',9-163, fig. i).— Studies by Sjollema of the drainage 

 water of 6 plats of land, each 300 square meters in area, during 4 years are 

 reported. 



The results show that the loss of nitrogen in the drainage water was very 

 small and practically negligible. Even when nitrogen was applied in the spring 

 in form of ammonium sulphate the losses were not large unless heavy rains 

 occurred at the time. The nitrogen is apparently rapidly taken up by the 

 young growing plants at this season of the year and only a small portion is 

 free to pass into the drainage. The greatest losses occur in the fall, when the 

 soil Is bare and heavy rains occur, the nitrates having accumulated in large 

 quantities during the warmer period of the year. Large losses at this season 



