148 ALFALFA FARMING IN AMERICA. 



is said that manure enough has been applied since 

 it has been in possession of the United States to 

 cover the soil with a layer several feet deep, and 

 yet the land is of only very moderate fertility. Why? 

 Because it is so lacking in carbonate of lime. 



Coming back to my father's idea that land could 

 be given such an impetus towards fertility and pro- 

 ductiveness that it would "keep a-going" it should 

 be said that it is only a partial truth, after all. 

 Doubtless the nitrogen content of the soil can be 

 maintained. In order to do this leguminous crops 

 should come with somewhat frequent recurrence, 

 since legumes restore nitrogen faster than anything 

 else we know. And alfalfa is the most vigorous ni- 

 trogen gatherer at our command. No one can store 

 a S'oil with fertility and draw upon it with maize 

 or oats or wheat or timothy grass without rapidly 

 depleting his store. All these things are soil rob- 

 bers; they do not create or secrete fertility for the 

 soil. 



Phosphorus Needed. Nor can legumes or alfalfa 

 do impossibilities. The mineral elements are pres- 

 ent in fixed amounts. Of potash one may have a 

 great abundance and on many soils need never 

 worry nor concern himself, but phosphorus is usual- 

 ly a thing needed and not in sufficient supply. It must 

 be remembered that plants cannot build their tissues, 

 form their blooms and mature their seeds without 

 using in regular "balanced ration " all the elements 

 of plant food. They cannot make use of an excess 

 of nitrogen profitably when phosphorus is in scant 



