WHEN DISK PLOWS ARE USED 



143 



FIG. 77. What happens when sod is plowed with a stubble plow. 



Fio. 78. First prize sod plowing. 



It is not so tiring, sir, to plow well, 



For your mind is interested. (English Plowman.) 



sod or light, loose soils when it is desirable to plow less than five 

 inches deep. The moldboard plow is recognized as a universal 

 plow. The disk plow is brought into service only when the mold- 



