Soil Fertility 91 



mixed and, for this reason, are more uniform and in a better 

 physical condition. The argument is fairly sound; neverthe- 

 less, experience shows that good results have been obtained 

 from home-mixed goods. By screening and mixing the mate- 

 rials thoroughly, a well-mixed fertilizer of good physical condi- 

 tion can be made at home. Experiments have shown that, as 

 a rule, home-mixing is cheaper than buying factory-mixed 

 goods, provided the ingredients can be purchased in large 

 enough quantities to warrant car-load shipments. The freight 

 rates are so high on small-lot shipments that the home-mixing 

 of small quantities usually does not pay. Cooperation among 

 farmers is here an advantage ; the organizations can buy in 

 large lots and distribute small quantities to the individual 

 members, thus taking advantage of wholesale prices and large 

 freight shipments. When deciding whether it will pay to 

 mix fertilizers at home, the farmer or organization should secure 

 quotations from dealers for both mixed goods of a given analysis 

 and the ingredients that will make this fertilizer and compare 

 prices. Usually it is well to figure a dollar a ton as the cost of 

 home-mixing, although quantities have been mixed for fifty 

 cents a ton. 



Method of mixing the ingredients. The operation of mixing 

 is not difficult. A smooth solid floor, shovels, a broom, a sand- 

 screen, and a stamper or a maul to crush out any lumps that 

 may be present are all the tools needed. A convenient stamper 

 can be made by fitting a handle into the top of a wooden block 

 about six inches by six inches by eighteen inches. Any lumpy 

 materials should be crushed and the different ingredients 

 should be placed in layers in a long pile. The pile is usually 

 mixed by two shovelers working opposite each other who start 

 at one end and turn the mass, a shovelful at a time, until the 

 other end has been reached. To insure good mixing, the pile 

 should be turned over at least three times. After each mixing, 

 the scattered parts at the edges should be swept into the pile 

 and, as soon as the mass has been well mixed, it should be 



