DRY-FARMING 



the later colonists have pushed cultiva- 

 tion into the dry central region and are 

 producing crops without the aid of ir- 

 rigation. From the earliest settlements 

 cereal crops have been grown almost 

 exclusively in this region. True, alfalfa, 

 timothy, corn, potatoes, and fruit are 

 now produced in many parts of the coun- 

 try. Yet they all sink into insignificance 

 in comparison with the grains — more 

 especially wheat. 



Tillage. 



In the Columbia Basin, where the 

 rainfall is light, wheat is grown every 

 other year alternating with the summer 

 fallow; where the rainfall is ample crops 

 are grown every year. Three reasons are 

 usually given in support of summer-fal- 

 lowing in this region: (a) To conserve 

 moisture. A large amount of wheat 

 being grown with an annual rainfall of 

 200 



