6 POTASH PAYS 



All of the foregoing crops also remove from the soil the 

 other two essential elements of plant food, which are phos- 

 phoric acid and nitrogen. Of course it is quite necessary 

 that all three of these plant foods be present in the soil in 

 order that the growing crops get suitable food or nourish- 

 ment. Potash, phosphoric acid, and nitrogen each have 

 their own value and do their separate work; so that one 

 can not take the place of the other. A proper mixture of 

 these three ingredients makes what is known as a * 'complete 

 fertilizer." The average farmer can usually make his own 

 mixtures. In fact, many farmers prefer to buy their potash 

 and other plant foods and mix them to suit their soil and 

 their different crops. The amounts of potash, phosphoric 

 acid, and nitrogen depend on the nature and condition of 

 the soil, as well as on the kind of crop to be grown: 



Another important point to remember is, that the quanti- 

 ties of plant food which each crop actually requires can not 

 be measured by the exact number of pounds of potash and 

 the other plants foods removed by that crop from the soil. 

 The reason is that plant roots can only reach a certain 

 amount of plant food in the soil, while the rest is not taken 

 up. Therefore, practical tests and experience have shown 

 that larger quantities of potash, phosphoric acid, and 

 nitrogen must be supplied than the actual number of 

 pounds per acre removed by the yield. 



The practical farmer and fruit grower will ask: "How 

 can I find out just what kind and how much fertilizing 

 material I should use for such and such a crop?" 



In reply, we would suggest that the farmer or fruit 

 grower make a few simple tests of fertilizers for himself, 

 and this each one can do at a very small amount of trouble 

 and expense. 



The best way is to lay out "experimental plots." You 



