PRINCIPLES OF MANURING. 



49 



In one aero to depth of one foot. 



Nitrogen. 



"Wheat soil .. 

 Timothy soil 

 Clover soil. . 



In Acid Extract. 



Phosphoric 

 acid. 



Potash. 



5,772 lbs. 



4,537 



4,735 



3,319 lbs. 



972 

 2,029 



3,89Glbs. 



4,861 



5,074 



No one of the above soils could grow a large crop of corn without 

 the help of manure, and yet the corn would require for its use but a 

 small fraction of the above quantities of nitrogen, phosphoric acid 

 and potash. Suppose the Farm Superintendent were to summer 

 fiiUow an acre of soil of like character and composition with the 

 ones analyzed. The crops that it would then be able to produce for 

 one year would be largely in excess of a crop grown on the land 

 without fallowing. Evidently cultivation works a change in the 



soil. 



Harris in his books on manures says that "Tillage is manure." 

 He is right. Soils contain inert plant food. Tillage renders it 

 active. It does this by causing more rapid disintegration. When 

 soil is turned over and over and thoroughly pulverized the ox3'gen 

 of the air can more readily act upon its organic, as well as mineral, 

 constituents. This increased yet slow combustion of vegetable 

 matter, aided by the solvent and decomposing action of its products, 

 renders useful material that before had been securely locked up. 

 We must remember that in most soils the upper layers are still a 

 storehouse of plant food, while the under strata are no less so, and 

 that cultivation is one of the efficient means of bringing such latent 

 material into useful activity. The farmer who makes good use of 

 his plows, cultivators and harrows, not onl}' renders his land easy 

 to work, and keeps down the weeds, but he helps feed his growing 

 crops. And here let me make a statement that farmers will do 

 well to heed. The use of a large quantity of yard or stable manure 

 should alwaj's be accompanied by thorough tillage. To the extent 

 that farmers fail in this respect, especially on heavy soils, to that 

 extent do they stand in danger of having quite a portion of the 

 manure lie inert in the soil for a long time. Tlie completeness with 

 which the manurial value of any organic fertilizer is utilized must 

 depend very largely upon the thoroughness of cultivation following 



