COMMERCIAL FERTILISERS 375 



The trade values of the different plant foods in 

 commercial fertilisers vary slightly from year to 

 year but generally a pound of nitrogen is worth 

 seventeen cents; a pound of potash four cents; a 

 pound of available or water-soluble phosphoric 

 acid, four and a half cents; this is what the 

 several plant foods can be bought for in raw fer- 

 tilising materials. The valuation of this partic- 

 ular fertiliser is: 



Per ton 



Nitrogen, 32.8 Ibs. @ 17 cents per Ib. . . . $ 5.57 

 Available phosphoric acid, 200 Ibs. @ 4^ cents 



per Ib 9.00 



Insoluble phosphoric acid, 80 Ibs. @ 2j cents per Ib. 1.80 



Potash, 180 Ibs. @ 4 cents per Ib 7.20 



Total value per ton $23.57 



Such a fertiliser may cost $36 per ton, or more. 

 The difference between this sum and $23.57, the 

 actual value of the plant food in it, covers the cost 

 of mixing, bagging, handling and the profit. On 

 an average it costs about $8 per ton to mix, bag, 

 and handle a ton of fertiliser before it finally 

 reaches the buyer, and allow a fair profit for all 

 concerned. If $8 is added to the actual plant food 

 value of a fertiliser, as determined from the 

 guaranteed analysis, the buyer knows what would 

 be a fair price to pay for the fertiliser. 



LOW-GRADE FERTILISERS EXPENSIVE 



To meet the demand for a cheap fertiliser a 

 lot of fertiliser for the money many manufac- 

 turers sell "low-grade fertilisers" for $15 to $26 

 per ton. But it costs as much to mix, bag, and 

 handle a ton of fertiliser containing $15 w^orth of 

 plant food as it does a ton of fertiliser containing 

 $30 worth of plant food. Furthermore, the cost 



