FEBTILIZER PRACTICB 555 



moisture, tend to disturb the application of such a law. 

 The fact that crop yield is the summation of so many 

 varying factors seems to argue in favor of no hard and 

 fast rule regarding the increased growth due to the added 

 increments of an element in the minimum. It is enough, 

 in the practical utilization of fertilizers, to remember that 

 this curve in general approximates the one already cited, 

 and that in order to obtain the best results from a com- 

 plete fertilizer a mixture should be used that is approxi- 

 mately balanced so far as the effects of the elements are 

 concerned, the crop as well as the chemical constitution 

 of the soil being considered. 



470. Fertilizer brands. — In an attempt to meet the 

 demands for well-balanced fertilizers suited to various 

 crops and soUs, manufacturers have placed on the market 

 numberless brands of materials containing usually at 

 least two of the important elements, and nearly always 

 the three; the former being designated as incomplete 

 fertOkers, whUe the latter are spoken of as complete 

 fertilizers. These various brands usually have some 

 catchy name, such as " The Ureka Corn Special," " Far- 

 mers' Potato and Corn Fertilizer," "The Golden Har- 

 vest," or "The Empire State Sure Crop Phosphate." 

 Such a name frequently implies the usefulness of the 

 material for some particular crop, but oftener it has no 

 relation either to crop or to soil. Ordinarily the name 

 should be ignored in the purchase of fertilizers. 



A brand of fertilizer is usually made up of a number 

 of materials containing the important ingredients. These 

 materials, already described, are called carriers. The 

 making-up of a commercial fertilizer consists, then, in 



aveo les Elements Nutritifs du Sol. Compt. Rend., Vol. 154, 

 pp. 1711-1714, 1912. 



