452 ANNUAL REPORT) OF THE Off. Doc. 



out going into further detail, it is sufficient to say, that in the |2,000,- 

 000,000 bushels, or over, of corn, there was contained: 



Nitrogen, equivalent to 6,000,000 tons of nitrate of soda. 



Phosphoric acid, equivalent to 2,738,000 tons of acid phosphate. 



Potash, equivalent to 452,000 tons of muriate of potash. 

 In the 61,000,000 tons of hay there was contained: 



Nitrogen, equivalent to 3,955,000 tons of nitrate of soda. 



Phosphoric acid, equivalent to 1,752,000 tons of acid phosphate. 



Potash, equivalent to 1,471,000 tons of muriate of potash, and in 

 the other crops, so large an amount of the constituents as to make 

 the total removed from the soil in these crops in a single year equiva- 

 lent to the: 



Nitrogen contained in 14,186,000 tons of nitrate of soda. 



Phosphoric acid contained in 6,902,000 tons of acid phosphate. 



Potash contained in 2,260,000 tons of muriate of potash. 



It will be observed that in this calculation, with the exception of 

 hay, the constituents removed represent only those in the grain or 

 seed; those contained in the straw and stalks are assumed to re- 

 main on the farm; and further, that the crops of tobacco, sugar-cane, 

 sugar beets, potatoes, pastures, and all fruits and vegetables are not 

 included. These figures are stupendous; their true significance can 

 hardly be comprehended even by those who do appreciate and can 

 foresee and safely predict the ultimate result of this annual and 

 continuous removal of plant-food under present methods of prac- 

 tice. 



The constituents contained in the stalks and straw, accompanying 

 these crops, and those that remained on the farm from the feeding 

 of part of the grains, are not sufficient, as is abundantly evident 

 from careful observation, to maintain the original fertility of the 

 soil, let alone its increase. It does not follow that the fertility of 

 our soils would be maintained at their former standard, even though 

 as much as possible of the constituents in these crops were returned, 

 as our methods of practice in many parts of the country, at least, 

 are such as to cause not only a loss of the constituents themselves, 

 but a loss of physical and chemical character, which makes a unit of 

 the constituents less efficient than under better conditions of prac- 

 tice. 



Some idea of the importance of these figures may, however, be ob- 

 tained when we place alongside of them in similar manner the 

 amounts of constituents that are returned to the soil in the form of 

 commercial fertilizers. In 1899, according to the United States 

 census, the farmers of the country paid |54,780,000 for about 

 2,700,000 tons of commercial fertilizers. Assuming an average com- 

 position of: 



Nitrogen, 2 per cent. 



■ Phosphoric acid, 8 per cent. 



Potash, 4 per cent. 



there was contained in these fertilizers, nitrogen, equivalent to that 

 contained in 253,500 tons of nitrate of soda, phosphoric acid, equiva- 

 lent to that contained in 1,380,000 tons of acid phosphate, and potash, 

 equivalent to that contained in 216,000 tons of muriate of potash. 

 Hence the total amount of constituents supplied by the fertilizers 



