LOSS OF NITRATES 



237 



examine a few results from the Rothamsted Experiment Station, 

 as compiled by Dr. Hopkins: 



NITROGEN IN DRAINAGE WATERS. ROTHAMSTED EXPERIMENTS 

 AVERAGE OF 12 YEARS (OR MORE). 



It does not necessarily follow that all of the nitric nitrogen 

 which is carried to a depth of sixty inches is lost to the growing 

 plant, for in work at the Utah Experiment Station the author and 

 coworkers have found in the spring a nitrate belt as low as the 

 seventh and eighth foot-section. These nitrates had been carried 

 to this depth by the winter and spring water. It was noted that 

 later in the season as the water was brought to the surface by 

 capillarity the nitrates also returned, and by June, July or August, 

 depending upon the crop grown upon the soil and the quantity of 

 irrigation water applied, the nitrate belt which in the spring was 

 in the seventh and eighth foot-section had reached the surface 

 foot-section*. Moreover, the deep-rooted plants of the arid regions 

 probably feed from lower depths than do the shallow-rooted plants 

 of the humid regions. 



The practical conclusion to be reached from these results is that 

 the method of reducing the loss by leaching is by growing plants, 



