17'J STATE BOARD OF AGRICULTURE. 



concentrated manure is almost indispensable; 2, The virgin soils of our 

 country i\o qoI make such demands for special manures as do the soils 

 o( the old world, depleted by centuries' constant cropping, in the new 

 lands o\' our State, which have practically lain fallow for a thousand 

 years, the need of now supplies of potash, nitrogen and phosphorus is not 

 so manifest, hence the introduction of commercial fertilizers has been 

 slow and halting, yet it is probable that by the present system o\' soil de- 

 pletion and neglect to preserve the natural fertility of our lands by rota- 

 tion id* crops and selling only \ he finished and most costly products of the 

 farm, the uso of commercial fertilisers will soon become an urgent 

 necessity . 



WHAT DC COMMERCIAL FERTILIZERS CONTAIN? 



The first question one asks about a now article is, "What is it made 

 of?" and t ho second is. ""Will a material of such composition and at the 

 Stated cost, give mo a profit when used on my farm'.'" 



Commercial fertilizers contain a variety o\ substances, but only 

 three of such importance that the farmer can afford to buy them at the 

 prices charged for concentrated manures. They often contain lime. 

 magnesia, silica, oxide of iron, sulphates, chlorides, etc., many of these 

 of value as manures, but they can be bought for less money than is 

 Charged for the commercial fertilizers. Tin 1 fertilizers may contain all 

 these, but we buy them because they contain in addition one or more 

 of three materials, viz., potash, phosphoric acid, and active nitrogen. It 

 is the presence o( these materials that gives commercial value to fer- 

 tilizers. If the dealer boasts that his manure also contains alumina, 

 silica, oxide of iron, lime and magnesia, the sufficient answer is that 

 these materials make up the mass of all soils, and that the farmer buys 

 his land by the acre and not by the ton. The only manural materials 

 that a farmer can afford to buy at prices demanded for fertilizers are 

 these three most necessary, most precious, and most easily exhausted 

 elements of plant growth — the tripod of agriculture. In the absence of 

 any one o\' these three materials no plant can grow to perfection, and if 

 the supply of them is below the needs of any given plant, that deficiency 

 limits the crop proportionally. However, abundant all the other ele- 

 ments Of plant life, nothing will make up for the lack of any one of those 

 three substances. 



WHERE POUND? 



in every good soil. The amount may vary in different soils, but every 

 soil that can produce any crop contains some of these materials. A con- 

 sideration of the composition of representative soils in our State may 

 .brow some lijgh?t on this subject. 



In former years the chemical department of ibis college soont much 

 time and toil in gathering specimens of leading soils from all parts of our 

 State, analyzing them, and mounting them in glass jars for exhibition. 

 the jars bearing labels to show the locality from which the soil came, 

 the kinds of timber growing on the land, and a chemical analysis of the 

 soil. A set id" 38 such mounted spociments was exhibited at the Colum- 

 bian Exposition in Chicago, for which a bronze medal was awarded. 



