CHAPTER III 



Nitrogenous Manures 



Nitrogenous Manures in General. 



The nitrogenous manures are the most hnportant 

 of all, and they are the dearest. They chiefly 

 assist the formation of the albuminous matter 

 in plants which constitutes the most valuable food. 

 When the law of the minimum is satisfied they 

 also assist very largely in increasing the bulk of 

 the crops. Soils which are deficient in assimilable 

 nitrogenous matters are incapable of producing 

 sufficient crops. And where these latter are 

 luxuriant the fact must be attributed to the 

 abundance of nitrogenous manure, the presence 

 of which is generally revealed by the dark or bluish- 

 green tint of the leaves. 



One important point to be considered, since 

 the unit of nitrogen is so dear, ought to be only to 

 choose manures in which the nitrogen is in easily 

 assimilable form. 



Fortunately for farmers there are on the market 

 a large and ever growing number of nitrogenous 

 products of a type suitable to supply the insuffi- 

 ciency in the soil. 



But as the unit of nitrogen is so dear it will be 



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