28 FARM ARITHMETIC. 



3. Determine the same in one ton (2,000 pounds) of 

 shelled corn. 



4. When the corn crop yields 25 bushels an acre of 

 shelled corn, how many pounds of nitrogen are required 

 from one acre of soil by the grain? How many of phos- 

 phoric acid? How many of potash? What is the total 

 weight of all three elements thus removed? 



5. When an acre yielding 25 bushels of corn in the 

 grain produces an average of 4,000 pounds (two tons) 

 of field-cured corn stover, how many pounds of nitrogen 



HOMEMADE TOOL FOR LIMING THE LAND. 



are removed from the soil in the stover; that is, by the 

 stalks exclusive of the grain and cob? How many of 

 phosphoric acid? How many of potash? How many 

 pounds of all three of these elements are removed by such 

 a crop of stalks ? 



6. What is the total amount of each of the three ele- 

 ments removed from one acre of soil by such a crop of 

 both grain and stalks? 



ANSWERS TO ABOVE QUESTIONS. 



(1) In 100 pounds of shelled corn of average quality, 

 there are of nitrogen 1.9 pounds or per cent, of phos- 

 phoric acid 0.7 pound or per cent, of potash 0.4 pound or 

 ner cent. 



