1694 Report of Farmers' Institutes 



In the ma«iiifacture of commercial fertilizers the chief supply 

 of nitrogen is from the nitrate beds of South America; the phos- 

 phoric acid is largely secured from the phosphate rock found 

 mainly in Tennessee and the Carolinas, and the potash comes from 

 the potash mines of Germany. 



An analysis of thirty-four soils in this state shows an average in 

 the first foot acre of 4,826 pounds of nitrogen, 5,904 pounds of 

 phosphoric acid and 26,386 pounds of potash. This average of 

 the mineral elements is maintained in each succeeding foot. Could 

 all these elements be made available as the plant required, to grow 

 20 Imshels of wheat an acre there would be nitrogen sufficient to 

 last 138 years, phosphoric acid 295 years and potash 753 years. 

 The fact that only a portion of this plant food is annually set free, 

 and that it is beyond one's power to determine just how much or 

 how little will go into solution during the growing season, the exact 

 amount of nitrogen, phosphoric acid and potash to apply to the land 

 to grow a given amount of any crop cannot be definitely fixed. 



Many manufacturers are placing on the market special brands of 

 fertilizers under the titles of " Potato Fertilizer " " Corn Fertil- 

 izer " and fertilizers for other crops. It is to be expected that 

 such fertilizers will be used on many kinds of soils and under 

 gTeatly varying conditions, and that the results derived from the 

 indiscriminate use of such mixtures must often prove a loss to the 

 buyer. 



For many years scientific men and institute lecturers have urged 

 farmers when buying commercial fertilizers to purchase them as 

 they would flour or sugar ; that is, to buy only the elements which, 

 after most carefully selected information and experiment, their 

 land seemed to require. 



Until very recent years but little progress has been made along 

 this line and farmers generally continued the buying of ready 

 mixed fertilizers. Now many are purchasing the chemicals and 

 cither applying them separately or are practicing home mixing. 



Perhaps one reason why home mixing of commercial fertilizers 

 is not more generally practiced is because farmers have not known 

 exactly how much of any element to use to produce the desired per- 

 centage. An example to ilhistrate how this is determined is given 

 below : 



