DRY-FARMING ZONES 



from 8 to 10 inches. So the rainfall of 

 one season is conserved for the use of the 

 next year's crop. (b) To eradicate 

 weeds. The yield of all grain crops is 

 greatly diminished when the land be- 

 comes foul with weeds, while the loss of 

 both moisture and plant-food is very 

 great, (c) To renew the fertility of the 

 soil. 



The corrugated roller and subsurface 

 packer have been introduced into this 

 region. Farmers in eastern Oregon 

 who use the roller state that their seed 

 germinates much better and that the 

 yield is several bushels more per acre 

 when they use the roller just after drill- 

 ing in the grain. It also enables them to 

 cut the grain much more easily and 

 cheaply because the ground is firmer at 

 harvest time. If neither the corrugated 

 roller nor the subsurface packer is avail- 

 able the disc harrow is used instead. It 

 203 



