THE PURCHASE AND MIXING OF FERTILIZERS 205 



2000 x .03 = 60 pounds nitrogen per ton 



2000 X .08 = 160 pounds phosphoric acid per ton 



2000 X .05 = 100 pounds potash per ton 



The next step is to calculate the number of pounds of the 

 carrier required to furnish the quantity of plant-food material 

 that has just been found. This is done by dividing the 

 weight of the plant-food material required by the percent 

 of this particular plant-food material in the carrier that is 

 to be used. 



60 •*- .15 = 400 pounds nitrate soda 

 160 ■¥■ .14 = 1143 pounds acid phosphate 

 100 + .50 = 200 pounds muriate of potash 

 1743 pounds of the three carriers 



The weights of the different carriers are then added, giving 

 in this case 1743 pounds needed for every ton of fertilizer. 

 The remainder of the ton (2000 - 1743 = 257 pounds) 

 is then made up with a filler, consisting of sand, dry earth, 

 muck, peat, sawdust or something of the kind. 



260. How to mix the ingredients. — A smooth tight floor 

 is needed on which each carrier is spread in turn to break 

 down the lumps. It is then passed through a coarse screen. 

 A weighed quantity of the filler or principal carrier is then 

 spread out in uniform depth and on top of it another carrier, 

 until all are represented. Then the pile is shoveled over and 

 over, and finally leveled and the process repeated until the 

 ingredients are thoroughly mixed. This lot of fertilizer 

 is then put in sacks and the operation repeated with another 

 quantity until a sufficient amount is prepared. There 

 should always be two hundred pounds or more of filler in 

 each ton to give a more uniform distribution of the carriers. 



QUESTIONS 



1. In what parts of the United States are fertilizers used in 

 greatest quantities ? 



2. What is meant by a brand of fertilizer ? 



