THE NEED OF LlME 



given prior consideration, and drainage is dis- 

 cussed in another place when methods of control- 

 ling soil moisture are described. The production 

 of organic matter is so important to depleted 

 soils, and is so dependent upon the absence of 

 soil acidity, that the right use of lime on land 

 claims our first interest. 



Soil Acidity. Lime performs various offices 

 in the soil, but farmers should be concerned chiefly 

 about only one, and that is the destruction of acids 

 and poisons that make the soil unfriendly to most 

 forms of plant life, including the clovers, alfalfa, 

 and other legumes. Lime was put into all soils by 

 nature. Large areas were originally very rich in 

 lime, while other areas of the eastern half of the 

 United States never were well supplied. Within 

 the last ten years it has been definitely determined 

 that a large part of this vast territory has an actual 

 lime deficiency, as measured by its inability to 

 remain alkaline or " sweet." Many of the noted 

 limestone valleys show marked soil acidity. There 

 has been exhaustion of the lime that was in a state 

 available for union with the acids that constantly 

 form in various ways. The area of soil thus defi- 

 cient grows greater year by year, and it can be 

 only a matter of time when nearly all of the eastern 



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