PERMANENT FERTILITY 



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Tooeland Farm : Clover and timothy, 1913. Check strip. 



fertilizer manufacturers and advertising agencies to use, would cost 

 about $75. 



Illinois Experiments. — As an average of 318 tests conducted in 

 southern Illinois during a period of eight years, two tons of ground 

 limestone, applied once in four years at a cost of about $2.50 per acre, 

 has produced an increase of 5 bushels of corn, 6^ bushels of oats, 4 

 bushels of wheat and i ton of hay; and where one ton per acre of fine- 

 ground rock phosphate was applied on the common corn-belt land in a 

 rotation of wheat, corn, oats and clover, the value of the increase pro- 

 duce paid back more than 100 per cent, for the first crop rotation and 

 nearly 200 per cent, for the second four-year period. 



On one of our oldest soil experiment fields on typical Illinois prairie 



