The Functions of Manures 



and prolongs the period of vegetation. When 

 assimilable nitrogen is applied in the springtime 

 the plants immediately become green and begin to 

 grow. But subsequent development is slow ; the 

 seed is formed later in the ear, and maturity re- 

 tarded. 



The luxuriant vegetation caused by the applica- 

 tion of assimilable nitrogen weakens the stalks of 

 the plants, renders them less resistant, and makes 

 the com more liable to " lay." That is why we have 

 recourse to potash which will give solidity and body 

 to the plants, and enable them better to resist the 

 elements. Ph. Ac. also acts to the same purpose. 



On the other hand, the addition of phosphoric 

 acid hastens the formation of grain and ensures 

 early maturity. The action of these three manures 

 therefore counterbalance and complete each other 

 so that there will be an abundant production of 

 strong growth of good quality, ripening in good 

 time. This last point ought to be taken into serious 

 consideration in regions where summer is short and 

 crops occasionally fail to ripen. 



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