FERTILIZER PRACTICE 575 



high point in production. The same continual shift 

 is found in the quantities applied. Too often 

 the specific brand used is determined by the trade 

 name that it carries or by the recommendation of 

 the retail merchant, rather than from a careful 

 consideration of the guarantee or of the carriers 

 for each important element. The educational 

 phase of home mixing should do much to eliminate 

 this system. 

 5. Fertilization of the money crop. — In trucking or in 

 general farming operations one crop is usually a 

 money crop. Naturally its stimulation by heavy 

 fertilization will pay better than applications to 

 crops that bring less on the market. The general 

 plan in this system is to allow the crops following 

 the money crop to utilize the residuum. When 

 this residual influence works out, the system is 

 likely to be a profitable one ; but when the follow- 

 ing crops fail to respond, the method becomes 

 wasteful in the extreme. 



In the selection of a system that will result in an ef- 

 fective utilization of fertilizers, only two of the plans de- 

 scribed above need be considered. In any fertilizer, 

 phosphoric acid and potash should always be present in 

 amounts sufficient to more than balance the nitrogen, 

 since the activity of nitrogen is so pronounced. There- 

 fore a scheme that calls for an abundance of minerals is 

 a sound one. This, coupled with the heavy fertilization 

 of the money crop, does not, however, constitute what 

 might be considered a rational system, since the crops 

 that follow may or may not be adequately supplied with 

 plant-food. Unwise fertilization often leaves the soil, 



