FERTILIZER PRACTICE 563 



as much per ton to market a low-grade material as a 

 high-grade one. This accounts for the fact that the ele- 

 ments are cheaper per pound in a high-grade mixture, 

 and that the value of plant-food received for every dollar 

 expended is greater. 



474. Home-mixing fertilizers. — In comparing the above 

 commercial evaluations with the prices actually paid 

 by the farmer on the retail market, it is found that the 

 latter shows an increase ranging from 48 to 100 per cent. 

 This is due to the charges for mixing, transportation, han- 

 dling, storage, commission, interest on capital, profit, 

 and other items, made during the passage of the material 

 from the wholesale dealer to the user. In order to escape 

 these costs, many farmers have begun the practice of 

 buying the separate carriers, thus avoiding these charges 

 — except, of course, that of transportation. In many 

 cases the mixing on the farm costs nothing, as it can be 

 done in winter when the farm work is not pressing. Even 

 if the farmer must charge himself with this mixing, it 

 seldom amounts to more than fifty cents a ton. 



As might be expected, this practice has met with much 

 opposition from manufacturers. In general it is claimed 

 that the factory goods are more finely ground than those 

 mixed by the farmer, and consequently the ready-mixed 

 goods are not only more uniform but also in better physi- 

 cal condition. Also, the manufacturer is able to treat 

 certain materials with acids, and thus increase their 

 availability. While these reasons are more or less valid, 

 good results may be expected from a fertilizer even though 

 it may not be quite uniform, as the soil tends to equalize 

 this deficiency. Moreover, by screening and by using 

 a proper filler, a farmer can obtain a physical condition 

 which will in no way interfere with the drilling of the ma- 



