EOTATION OF CROPS 55 



sene would be quite analogous to the case of the 

 farmer who decided against the use of a rota- 

 tion of crops and bought commercial fertilizers 

 to keep up the fertility of his land. 



Diversity and rotation of crops tackle the 

 same proposition from different angles but they 

 arrive at much the same result. Rotation is 

 diversity to a degree, but diversity is not neces- 

 sarily rotation. Diversity, ipso facto, is a 

 purely business proposition. It does not take 

 account of the fertility of the soil or of its con- 

 servation or improvement. It divides the risks 

 of crop failures, and makes a profitable distri- 

 bution of labor. Rotation is designed, primar- 

 ily, to increase crops without corresponding 

 cost, but with it goes the corollary of increased 

 fertility. Incidentally it does produce diversity 

 with the consequent efficient use of labor. 



When crops, per acre, can be increased with- 

 out additional cost for fertilization or cultiva- 

 tion, the profits rise more rapidly than the 

 yields. 



The following figures are taken from careful 

 experiments : 



