562 SOILS: PROPERTIES AND MANAGEMENT 



particular brand should be purchased or not. The real 

 question here is not the actual quantities of the elements 

 in a ton of the fertilizer, but their balance among them- 

 selves. The actual pounds of nitrogen, phosphoric acid, 

 or potash applied per acre can be governed by the rate 

 at which the mixture is applied. 



The purchase of high-grade goods is the second impor- 

 tant point to be considered. Data collected from practi- 

 cally every state show that the higher the grade of the 

 fertilizer, both as to availability and as to the percentage 

 of the constituents carried, the greater is the amount of 

 plant-food obtained for every dollar expended. The 

 following data, taken from Vermont l for 1909, are the 

 average of one hundred and thirty brands and are typical 

 data in this regard : — 



It is noticeable at once that the lower the grade of the 

 fertilizer, the higher is the proportional cost of placing 

 the goods on the market. In other words, it costs just 



1 Hills, J. L., Jones, C. H., and Miner, H. L. Commercial 

 Fertilizers. Vermont Agr. Col., Bui. 143, pp. 147-149. 1909. 



