20 



SOILS OF THE TKUCKEE-CAESON lEEIGATION PROJECT. 



standpoint. The results are all expressed in Table I as parts of 

 nitrogen per million of the solution. 



Fig. 1.3. — Diagram showing the nitrification of ammonium sulphate in samples of soil from different depths 

 from plats 280 and 290, Truckee-Carson Experiment Farm. Original nitrate present in samples from 

 plat 2S0: Depth, to (i inches, 12 parts per million; 6 to 12 inches, 10; 12 to IS inches, 6; 18 to 24 inches, 

 15; 24 to 36 inches, 62.S. From plat 290: Depth, to 6 inches, 60 parts per million; 6 to 12 inches, 60; 

 12 to IS inches, 55.4; 18 to 24 inches, 60; 24 to 36 inclies, 60. 



Table I. — Nitrification in solution of samples of soil from plats 100. IW. 180, 190, 

 260, 270, and 280,^ Truckee-Carson Experiment Farm. Incubated at 28° C. 



220, 



> Plat 280 is locatod in an old alfalfa field one-fourth mile north of Fallon. 



s Used medium for isolating nitrite bacteria. '■> Used medium for isolating nitrate bacteria. 



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