TWENTY-FOURTH CHAPTER, 



PLANT FOODS NEEDED IN ORDINARY 

 CROP ROTATION. 



"IITHEAT, clover, potatoes, corn, oats — that or a 

 similar one is the five-year crop rotation 

 quite generally practiced by good farmers at the 

 north. With slight variations or modifications it is 

 sometimes kept up on the same place for many 

 years. Of course we desire to know the amount of 

 plant foods that we remove from the soil in these 

 crops. A fairly good yield per acre is approxi- 

 mately as follows: thirty bushels of wheat; two 

 tons of clover hay; 200 bushels of potatoes; fifty 

 bushels of corn; and forty-five bushels of oats. A 

 good farmer, who knows how to make farming pay, 

 rarely raises less, and often more, provided the land 

 had not been run to death before he came in posses- 

 sion of it, or during his early occupancy, while he 

 was yet without experience in feeding his crops. 

 During the five-year period the following plant 



