16 WHEAT CULTURE. 



dients, in order that they may be taken uj> in plant 

 growth ; otherwise failure is certain. Liebig and other 

 chemists and experimenters have proved that but small 

 quantities of potash and silica are necessary, but that 

 these small quantities are absolutely essential, as are 

 moisture and air those powerful solvents which reduce 

 the constituents of the soil to a liquid state, so that plants 

 can use them. 



FIFTH CLOVER AND PLASTER. 



With the above preparation thoroughly made that is, 

 under-draining and sub-soiling plaster, on clover plowed 

 under in rank growth, and with the use of good seed 

 wheat a yield of thirty to forty bushels the acre of sound 

 wheat will be the result, three years out of four, as 

 surely as fifteen to twenty is from the ordinary farm 

 operations. If the drainage be thoroughly done, and the 

 sub- soiling well done, twelve to fifteen inches deep, the 

 sub-soiling will not be required oftener than every four 

 or five years, and the ordinary plowing need not be more 

 than six or seven inches deep in the intermediate years, 

 and for plowing under clover or other green crops, or 

 any manure, the plowing need not be more than five or 

 six inches deep, with mellow sub-soil. 



In order not to bring raw sub-soil to the surface, it is 

 best to cut the main furrow eight to ten inches deep with 

 a large plow and stout team. Then follow in that furrow 

 with a single horse and small, narrow plow, which will 

 break the sub-earth four to six inches deeper and not 

 quite so wide as the first furrow, and the next furrow 

 will fall into and cover the small one, leaving the old 

 surface soil still near the top. Most farmers know of 

 and have used the small, sharp sub-soil plows made on 

 purpose for that work, and to great advantage. 



It is found to be a good plan to apply the alkalies 

 ashes, lime, potash, and salt, or whatever is used to tl^e 



