228 



THE FIRST BOOK OF FARMING 



This assumes that we have taken from the farm 

 in products sold : 



The plant food charged to animal products is 

 twenty per cent, of that in the grain and forage fed 

 to the stock. 



At the end of the three years the plant food ac- 

 count will balance up with: 



Nitrogen a gain of 2 pounds. 



Phosphoric Acid a loss of 16 " 



Potash a loss of 22 " 



This result is of course approximate. There will 

 be some loss of nitrogen through leaching and deni- 

 trification. Some of the potash and phosphoric acid 

 will be converted into unavailable forms. This can 

 be made good by applying to the cotton a fertilizer 

 containing twenty pounds of nitrogen, sixty pounds 

 of phosphoric acid and twenty pounds of potash. 



Additional nitrogen and organic matter can be 

 grown to turn under by planting crimson clover 

 in the cotton at the last working for a winter cover 

 crop to be turned under for the corn, and by plant- 

 ing cowpeas or soy beans between the rows of corn. 



