6 FERTILIZERS. 



The order in creation,' then, is, that the rocks supply the 

 minerals ; plants feed on these minerals ; animals feed on 

 these plants ; while omnivorous man, lord of all, feeds on 

 both minerals and plants. 



Chemists have settled the fact that most of the dozen 

 elements that enter into the composition of plants are 

 found in sufficient quantity in almost all soils, leaving but 

 potash, nitrogen, and phosphoric acid as the three essen- 

 tials, more or less of each of which, as a general rule, we 

 farmers must supply to the soil if we plant for a crop ; 

 though on some soils, such as muck meadows, lime and 

 silicon in some form may be necessary adjuncts. We pro- 

 pose to discuss these, and. the sources from which they are 

 obtained. 



Before taking up in detail the three essential elements 

 of plant-food, let us here discuss the difference that is 

 assumed to exist between them as they exist in barn 

 manure and commercial fertilizers. 



WHAT IS THE DIFFERENCE BETWEEN BARN MANURE AND 

 COMMERCIAL FERTILIZERS ? 



All plant-food is manure ; and all manure is plant-food, 

 whether it is in the form of the artificial products, which 

 are known among farmers as "artificial manures," "chemi- 

 cal fertilizers," or is the natural product of the barn 

 yard : and the feeding value of each is measured in the same 

 way ; viz., by the quantity they contain of the three essen- 

 tial elements, viz., nitrogen, potash, and phosphoric acid, 

 and the digestible condition in which these elements exist. 

 The great bugbear dealers in fertilizers have to contend 

 with in dealing with us farmers is, the deeply rooted belief 

 that the only real manure is that which comes out of the 

 barnyard, and that all other forms in which it is presented 

 are mere makeshifts. 



