CROPS AND SOIL IMPROVEMENT 



its use is not advised until the spring of the year 

 in which timothy will be harvested. 



All the Nitrogen from Clover. The Penn- 

 sylvania station has shown in a test of thirty years 

 that when good clover is grown in a four years' 

 rotation of corn, oats, wheat, and clover, the fer- 

 tility of the naturally good clay loam soil may be 

 maintained, and even slightly increased, without 

 the use of any manure or purchased nitrogen. 

 Phosphoric acid and potash have been applied, 

 and the clover hay crop has been taken off the 

 land. This result has been possible only by means 

 of good clover sods. If there had been no ap- 

 plications of phosphoric acid and potash, the 

 clover would have failed to maintain fertility, as 

 is proved by other plats in this experiment. No 

 one should continue to depend upon such a scheme 

 of keeping land fertile whenever he finds that the 

 clover is not thriving. 



Method of applying Fertilizers. If a fertilizer 

 is used in small amount with the purpose of merely 

 giving the plants a start, it should be near the 

 seed. If the application is heavy, and the roots 

 of the plants spread upon all sides, the fertilizer, 

 as a rule, should be applied to all the ground, and 

 should be mixed with the surface soil. This puts 



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