354 



ANNUAL REPORT OF THE 



Table IX. 



Off. Doc. 



!Nitrogea as Nitrates ia Soil and Subsoil and in the Drainage Water 

 of Various Plots in the Broadwalk Wheat Field, in Pounds Per 

 Acre. 



Plot. 



Character of Manuring. 



2,.. 

 5 a, 



10 a, 



7 a, 



11 a, 



8 a, 



Unmanured. 

 Mixed mineral manure. 

 400 lbs. ammonium salts, 

 do. + mixed minerals, 

 do. 4- super-phosphate. 

 600 lbs. ammonium salts 

 minerals. 



and mixed 



From the above we note that the total nitric nitrogen in 27 inches 

 of unmanured soil was 17.8 pounds per acre; while in the same soil, 

 treated with mixed mineral fertilizers, the amount was 24.3 pounds 

 per acre. 



The percentage of nitric nitrogen which passed out in the drainage 

 was also diminished as a result of the application of mineral fer- 

 tilizers. 



The effect of mixed minerals, when applied with ammonium salts 

 in diminishing the loss of nitrates in the drainage, is well shown in 

 the results from Plot 10a, 7a, and 8a, in the preceding table. 



The Hfect of Season of Year Upon Loss of Nitrates. 



The preceding table shows that in unmanured land, and in land to 

 which only mixed fertilizers, free from nitrogen, had been applied 

 the percentage of nitric nitrogen removed by the drainage from Sep- 

 tember 1 to February 1, five months, was from 54 to G5 per cent, of 

 the total quantity present in the first 27 inches of soil at the begin- 

 ning of the experiment. In Table VIII similar results are observed. 



On Plot 5, fertilized by non-nitrogenous manures, the average num- 

 ber of parts of nitrates per million parts of drainage for the whole 

 year was 4.2 while the corresponding figures for the periods from 

 wheat harvest to autumn sowing, and from autumn sowing to spring 

 sowing, were respectively 4.8 and 5.5. The corresponding figures for 

 the periods from spring sowing to the end of May, and from June to 

 harvest, were 2.9 and 0.2. 



