CHAPTER V 



WOEKING THE SOIL 

 IMPORTANCE OF PLOWING 



Plowing is a mechanical operation that deals with 

 physics, chemistry, bacteriology and entomology. The 

 soil is the farmer 's laboratory ; his soil working imple- 

 ments are his mechanical laboratory appliances. A 



Figure 132. Heavy Disk Plow. A strong four-horse disk imple- 

 ment for breaking stumpy ground or to tear tough sod into bits be- 

 fore turning under with a moldboard. 



high order of intelligence is required to merge one op- 

 eration into the next to take full advantage of the 

 assistance offered by nature. The object of plowing 

 and cultivation is to improve the mechanical condition 

 of the soil, to retain moisture, to kill insects and to pro- 

 vide a suitable home for the different kinds of soil bac- 

 teria. 



There are aerobic and anaerobic bacteria, also nitro- 



137 



