PREPARATION AND PLANTING 



165 



soil for the present crop, so much as the kind of treatment 

 it has had for the last ten or twenty years. The kind of 

 treatment to be recommended must consider more the 

 future -welfare of the land, than present benefits to be 

 derived. 



TABLE XXXVI 

 Yield op> Coen in Bushels 



1 Tons of green silage. Depths were 3, 5, 7, and 9 inches. 



' Also subsoiled 6 inches deeper. ' Depths 3 and 7 inches. 



So far as tillage is concerned, as a factor in maintaining 

 crop production, the following principles may be set forth : 



That all land should occasionally be plowed 8 to 10 

 inches deep. On heavy land about once a year, but on 

 lighter soil, and in rather dry regions, once in two or three 

 years being sufficient. 



The plowing should be done when the land is in proper 

 condition to pulverize. 



Quite thorough treatment with pulverizing tools, as 



