STABLE MANURE 



can return to the fields at least four fifths of all 

 the plant-food taken out by the crops, and we 

 loosely reason that such a scheme is demanded by 

 nature. The maintenance of fertility involves 

 good arithmetic, and a plant must have certain 

 weights of mineral elements at command before 

 it can grow, but it is not true that the productive 

 power of land is chiefly dependent upon the return 

 to it in manure of all the fertility removed by its 

 crops. If this were true, meat and other animal 

 products would be the sole food supply of the 

 world's markets. 



The Place for Cattle. There are general 

 trends in human practice that cannot be changed 

 by man. A change in human diet that makes the 

 percentage of meat lower will not come through 

 propaganda, but there are forces at work that will 

 restrict the consumption of meat by the individual. 

 The increase in population makes heavier demand 

 for food. Armsby has shown that the fattening 

 steer returns to man for food only 3 per cent of 

 the energy value of the corn consumed by it, and 

 in pork-production this percentage scarcely rises 

 to 16. This is the reason meat-making animals 

 give way before increase in population in con- 

 gested countries. Their office becomes, more and 



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