130 



BACTERIA AND SOIL FERTILITY 



form nitric nitrogen into protein nitrogen and the speed with 

 which this change occurs may at times become important, that is, 

 work at the Utah Experiment Station indicates that this may at 

 times reach twenty or thirty pounds per acre yearly. 



Nitrogen in Drainage Waters. Rothamsted Experiments 

 Average of xi Years (or More) 





Rainfall 

 {in) 



Bare Soil — 6o4nch Gauge 



Wheat Land 



Month 



Drainage 

 {in,) 



Nitrogen 



Nitrogen 





Per Mtllion 



Pounds Per 



Per Million 









of water 



Acre 



of water 



January 

 February 

 March 

 April 



2.13 

 2.16 



1.70 

 2.25 



1-93 

 1.74 



•94 



•79 



8.9 

 9.1 

 8.9 

 9.0 



3.88 



3.57 

 1.89 



1.61 



3.1 



4.0 



2.0 

 1.9 



May 

 June 

 July 



August 



2.48 



2.59 

 2.85 



2.69 



•79 

 .78 



.62 



.76 



9.1 



9.1 



11.8 



1.63 

 1.60 

 1.66 



2.28 



•9 

 .1 



.1 



.1 



September 

 October 

 November 

 December 



2.70 

 3.12 

 3,20 

 2.34 



.82 

 1.68 

 2.32 

 1.88 



13-4 

 11.9 

 11.4 

 10.6 



2.50 

 4.53 



4.51 



3.9 

 4.6 



3-6 



4.8 



January-April 

 May-August 

 September- 

 December 



8.24 

 10.61 



11.36 



5.40 

 2.95 



6.70 



9.0 

 10.6 



n.8 



10-95 

 7.17 



17.52 



2.8 

 •3 



4.2 



January- 

 December 



30.21 



15.05 



10.5 



35.64 



2.4 



These factors must always be kept in mind in an attempt to 

 reach general conclusions from any special cases, yet it is instruc- 

 tive to examine a few results from the Rothamsted Experiment 

 Station, as compiled by Dr. Hopkins. 



It does not necessarily follow that all of the nitric nitrogen 



