8 



SOILS OF THE TRUCKEE-CARSON IRRIGATION PROJECT. 



little importance. The quantity of nitric nitrogen originally present 

 is shown in the legends under the diagrams (figs. 2-13). 



A description of the Truckee-Carson Experiment Farm, at Fallon, 

 Nev., upon which practically all of the work herein reported was con- 

 ducted, is given in a previous bulletin of this Bureau.^ The designa- 

 tions of the small ])lats from which samples were taken for bacterio- 

 logical study and their location are shown in figure 1. 



N. 



320, ,350 



30 



40^ 



m 



n 



330' / \ ^340 

 300 310 



2?0 



240 

 4-250 



270' 



Fig. 1.— Location of sampling plats in the experimental fields of the Traekee-Carson Experiment 



Farm south of Fallon, Nev. 



METHODS EMPLOYED IN BACTERIOLOGICAL INVESTIGATIONS 



OF THE SOIL AT FALLON, NEV. 



REQUIREMENTS TO BE MET. 



Investigations in soil bacteriology require first of all the selection 

 and development of satisfactory methods for determining the dis- 

 tribution and activity of the micro-organisms which may occur under 



' Scofield, C. S., and Rogers, S. J. The Truckee-Carson Experiment Farm. Bul- 

 letin 157, Bureau of Plant Industry, 1909. 

 211 



