CULTIVATING AND CROPPING 



comes on. A fairly deep digging and lump 

 crushing tool is the best implement to use up 

 to this time, and a disk or spring-tooth harrow 

 meets these requirements. 



After this period Is passed and during drier 

 weather, cultivation Is carried on for a different 

 purpose, namely, to conserve moisture by mak- 

 ing a thin dust mulch of soil over the surface. 

 This is best accomplished by shallow-going im- 

 plements of which the spike-tooth harrow, the 

 acme harrow, or a light wheel cultivator are 

 best. As the season and the amount of rain- 

 fall vary, so must tillage operations be varied. 

 In an early dry season begin with the lighter 

 Implements earlier. In a late wet season keep 

 the digging tools at work later. As soon as the 

 soil Is In good physical condition the principal 

 object of tillage is to modify moisture con- 

 ditions. 



As a matter of practice three to four harrow- 

 Ings at Intervals of a week to ten days are 

 necessary. Sometimes more, sometimes less 

 are required, according to the character and 

 condition of the soil and the season. The later 

 moisture-conserving tillage should also be car- 

 ried on every week or ten days, according to 

 weather conditions. It Is good practice to stir 



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