FERTILITY IN SOILS 365 



would seriously interfere with the growth of plants ; as a 

 matter of fact it seems to have little effect. Experiments showed 

 that plants readily took up the decomposition products — am- 

 monia, etc. — and were not dependent on nitrification, although 

 they made rather better growth per unit of nitrogen absorbed 

 if supplied with nitrate than if supplied with ammonia. 

 Considerable care is necessary to prevent reinfection ; the 

 nitrifying organisms are so small and so widely disseminated 

 that, unless special precautions are taken, they speedily gain 

 an entry into the treated soils and nitrify the ammonia as it 

 is formed. 



Literature dealing with Partial Sterilisation of Soil 



Oberlin, Bodenmiidigkeit und Schwefelkohlenstoff, Mainz, 1894. 



Girard, A., Bulletin de la Societe Nationale d' Agriculture e?i France, 1894, vol. liv. 



P- 35°- 

 Frank, B., Berichte der Deutschen BotaniscJien Gesellschaft {Generalversammlungs 



Heft), 1888, vol. vi. p. 89. 



Koch, A., Arbeile?i der Deutschen Landwirtschaft-Gesellschaff, 1899, Heft 40. 



KRUGER, W., Landwirtschaftliche Jahrbiicher, 1905, vol. xxxiv. p. 761. 



Hiltner, L., and Stormer, K., Arbeiten aus der Biolog. Abteilung fur Land- 

 tend Forstwirtschaft am Kaiserlichen Gcsundheitsamte, 1903, vol. iii. 



Hiltner, L.,fa/iresberictite der Vereinigung fur Angewandie Botanik, 1907, p. 200. 



Russell, E. J., and Darbishire, F. V., Journal of Agricultural Science, 1907, 

 vol. ii. p. 305. 



Pickering, S. U., ibid. 1908, vol. ii. p. 411 ; vol. iii. p. 32. 



Russell, E. J., and Hutchinson, H. B., ibid. 1909, vol. iii. p. in. 



