AGRICULTURAL ECONOMICS 



grades of land. It will prove profitable to farm 

 the more productive land more intensively before 

 it will prove profitable to farm the less productive 

 land at all. When it is profitable for a farmer to 

 apply X units to C grade land it will prove equally 

 profitable for him to apply Y units to B grade 

 land and Z units to A grade land. 



We are now in a position to see more clearly the 

 influence of varying degrees of intensity of cul- 

 ture upon differential rents. In the illustration 

 the surplus which a given farmer can produce on 

 A grade land ( Fig. 5 ) , over what he can produce 

 on C grade land is represented by the area 

 K M N E, which is greater than the area 

 KMNP by the area P N E; but the area 

 K M N P measures the difference in the value of 

 the product which he could produce on the two 

 pieces of land with the same outlay. The surplus 

 which the same farmer can produce upon B grade 

 land, over what he can produce upon C grade land 

 is represented by the area K L O D; that of A 

 grade land over B grade by area L M N E D 0. 

 Hence, it is not simply differences in productivity 

 with the same outlay, but it is the differences in 

 the capacity of the land to yield a surplus, that 

 determines how much more highly a farmer will 

 estimate one piece of land than another of the 

 same area. 



The theory of rent would be quite simple if it 

 could be said that the differential rent of land is 

 164 



