Agricultural Chemistry. 



basal materials mixed together to give the desired per cent of 

 nitrogen, phosphoric acid and potash. 



Nitrogenous fertilizers. This group of substances may be 

 divided into two classes: (1) Inorganic or mineral substances; 



Complete 

 Fertilizer 



Without 



Phosphoric 



Acid 



Without 

 Potash 



Withoul 

 Nitrogei 



Effect of fertilizer constituents upon oats grown on clay soil. Note 

 scarcity of foliage where no nitrogen was supplied and the 

 yield of grain where phosphoric acid was lacking. 



(2) organic substances derived from animal or vegetable rm 

 rials. The inorganic materials most commonly used are sulphate 

 of ammonia, nitrate of soda and nitrate of potash. 



