58 INDIAN CORN CULTURE. 



CHAPTER V. 



MANURES AND FERTILIZERS. 



It is a generally recognized fact that to re- 

 move a crop from the soil is to take from it a 

 certain amount of fertility or plant food. If 

 this practice is continued without returning 

 this food in some form to the soil it becomes 

 much impoverished and less and less produc- 

 tive. 

 ^^p^ Fertilizers necessary.— A crop of 50 bushels 

 ''of Indian corn and 8,000 lbs. of cornstalks per 

 acre will remove from the soil 79.8 lbs. nitro- 

 gen, 55.2 lbs. phosphoric acid and 87.6 lbs. 

 potash.* To remove such a crop is a heavy 

 drain on the soil fertility, and to purchase in 

 the markets the amounts of nitrogen, phos- 

 phoric acid and potash removed by it would 

 cost about $20. In the great corn-growing 

 region of the country, however, a large amouiit 

 of land is annually planted which contains so 

 much available plant food that the farmer 

 does not feel justified in placing artificial ferti- 



* Science in Farming, 1882, p. 153= 



