No. 4.] COMMERCIAL FERTILIZERS. 127 



of plant-food clt'iiicnts as it is a (iiicslion of amount applied. 

 First, see to it that an abuiidance more ])arli('ulai'lv of the 

 minerals are furnished, and the jn-oportions will take care of 

 themselves. This, of course, is only true in a general way. 

 Formulas arc good, but theoretically it is not a question of 

 fornnda but a question of giving a plant that which it needs 

 at the time it needs it. We are surely wasteful in the use 

 of connnercial fertilizers, first, because we use them unsys- 

 tematically, without definite relation to character of crops, 

 rotations, seasons, soils or object of growth ; and in the 

 second place, we are using them foolishl}^ because we don't 

 know what we are using or why we are using it, and thus 

 often get absolutely no return. 



The previous treatment of soils, so far as cropping and fer- 

 tilization are concerned, also has a bearing uix)n the matter 

 of present fertilization. It is a well-known fact that contin- 

 uous cropping will result in the greater depletion of not 

 only one or more elements of plant food, but that, unless 

 accompanied by cover crops and green manures, will result 

 in a very rapid removal or loss of organic matter, thus caus- 

 ing the condition of soil to be less favorable for the absorp- 

 tion and distribution of fertilizers than would be the case 

 if " condition " was maintained. In the east, this method is 

 not generally used ; nevertheless, the practice often followed 

 results in practically the same thing. In many instances, 

 grain crops, like corn, oats and wheat, are grown exclusively 

 for sale. That is, the grain is sold in all cases, and only 

 enough stock kept to carry on the work of the farm, thus 

 making the returns to the soil consist chiefly of the straw 

 and stalks which accompany the grain. 



This kind of farming results in a very rapid removal of 

 the phosphates, more particularly as the grain contains a 

 larger proportion of these, while the potash and nitrogen 

 would be returned in greater amounts. Hence, cropping of 

 this sort would require different fertilizers than if the 

 purpose of the farming had been to utilize all of the products 

 raised upon the farm. In farm practice of this kind, there- 

 fore, if it is to be profitably continued, there will be a rela- 

 tively greater demand for phosphates and nitrogen than for 



