340 



AGRICULTURAL ECONOMICS 



The experiment was continued, and at the end of fifty-two years 

 the results were as follows: 



These figures for half a century show the same principle of 

 diminishing returns in a modified form. Owing to soil exhaustion, 

 the yields from the unfertilized land decreased during the fifty-two 

 years. On account of a few bad seasons, the average effect of the 

 first dose (200 pounds) was slightly decreased. Owing to the accumu- 

 lation of residues of fertilizer, the effects of the second and third doses 

 were relatively larger than for the twelve-year period, though subject 

 to the same law of diminishing returns. That is to say, the last dose 

 of fertilizer was less than half as effective as the first; or, what is the 

 same thing, the last increment of increase cost more than twice as 

 much per bushel as the first. 



In the more intensified agriculture that is just ahead of us the 

 question is, therefore, not how much the farmer can produce per acre, 

 but how much he can a/ord to produce. His yield must depend, not 

 mainly upon his knowledge of production, but upon the price of the 

 product. 



For example, in the tables quoted, each 200 pounds of fertilizer 

 cost $7 . 50. With wheat at a dollar a bushel, a little computation will 

 show that both the single and the double applications would pay, but 

 that the triple application would swallow all the profits and more. At 

 eighty cents a bushel, none of the treatments would pay, and both 

 the farmer and the public would have to be contented with the lower 

 yields from untreated land until such time as the consumer was 

 willing to pay a higher price for his food. In this way is yield depend- 

 ent upon price, and it is the natural way in which supply adjusts 

 itself to demand as expressed in price. 



Of the same tenor is the experience of the University, which is 

 producing corn yields varying from 26 bushels per acre on continuously 

 unfertilized land to an average of 93 and a maximum of 120 bushels 

 per acre on land which is excessively fertilized. It is making no 

 money on either extreme: in the one, because the yield is not sufficient 



