CROPS AND SOIL IMPROVEMENT 



board is to get out of the soil. There is no evi- 

 dence that lime is not in sufficient quantity in 

 most soils to feed crops adequately, but within 

 recent years we have learned that vast areas do 

 not contain enough lime in available form to keep 

 the soil from becoming acid. Some soils never 

 were rich in lime, and these are the first to show 

 evidence of acidity. In our limestone areas, how- 

 ever, acid soil conditions are developing year by 

 year, limiting the growth of clover and affecting 

 the yields of other crops. 



The situation is a serious one just in so far as 

 men refuse to recognize the facts as they exist, 

 and permit the limiting of crop yields, and conse- 

 quently of incomes, through the presence of harm- 

 ful acids. The natural corrective is lime, which 

 combines with the acid and leaves the soil friendly 

 to all plant life and especially to the clovers and 

 other legumes that are necessary to profitable 

 farming. Nature is largely dependent upon man's 

 assistance in the correction of soil acidity. 



Crop-rotation. A good crop-rotation favors 

 high productiveness. One kind of crop paves the 

 way nicely for some other one. The land can 

 be occupied by living plants without any long in- 

 termissions. Organic matter can be supplied 



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