CHAPTER X 
PLOWING AND FALLOWING 
THE soil treatment prescribed in the preceding 
chapters rests upon (1) deep and thorough plowing, 
done preferably in the fall; (2) thorough cultivation 
to form a mulch over the surface of the land, and (3) 
clean summer fallowing every other year under low 
rainfall or every third or fourth year under abundant 
rainfall. 
Students of dry-farming all agree that thorough 
cultivation of the topsoil prevents the evaporation of 
soil-moisture, but some have questioned the value of 
deep and fall plowing and the occasional clean sum- 
mer fallow. It is the purpose of this chapter to state 
the findings of practical men with reference to the 
value of plowing and fallowing in producing large 
crop yields under dry-farm conditions. 
It will be shown in Chapter XVIII that the first 
vattempts to produce crops without irrigation under a 
limited rainfall were made independently in many 
diverse places. California, Utah, and the Columbia 
Basin, as far as can now be learned, as well as the 
Great Plains area, were all independent pioneers in 
the art of dry-farming. It is a most significant fact 
that these diverse localities, operating under differ- 
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