572 SOILS: PROPERTIES AND MANAGEMENT 



FERTILIZER FORMULAS FOR GENERAL APPLICATION 



While it is recognized that these formulas are probably 

 far from correct in their application to such groups as 

 the garden crops, where so many entirely different plants 

 are concerned, it is felt that they furnish the basis, as 

 far as our knowledge now extends, for a more economic 

 fertilization. The variation of such mixtures to suit 

 specific needs is a part of fertilizer practice. 



The carriers largely used for such readily available 

 mixtures are sodium nitrate, acid phosphate, and potassium 

 chloride or sulfate. Tankage or blood is often substituted 

 for sodium nitrate where humus is desirable, while am- 

 monium sulfate and calcium cyanamid are growing in 

 popularity. Raw rock phosphate and basic slag are used 

 rather largely in separate applications, the amounts 

 being usually larger than with the ordinary fertilizer 

 materials. 



The other phase of fertilizer practice is In the amount 

 to be applied. With all the groups considered above 

 except garden and root crops, the applications are rela- 

 tively light, ranging from 150 to 300 pounds to an acre. 

 Where excessive vegetative growth is required, as in silage, 

 the rate may be increased to 500 pounds. In the top- 

 dressings of meadows or grains, the rate varies from 75 



