DRY-FARMING ZONES 



in this region. By far the larger part of 

 the Great Basin lies at an altitude of 

 over 4200 feet above sea level. The 

 farms in the valleys above the water- 

 courses have mostly been placed under 

 irrigation, while those on the higher 

 mesas ^ which cannot be reached by canals 

 remain to be reclaimed by dry- farming. 

 On a map the Great Basin looks just like 

 a huge mass of protoplasm as seen under 

 a high-power microscope with three ir- 

 regularly shaped arms. One arm reaches 

 into Oregon, another into California, 

 and the third into Utah ; but the body lies 

 altogether in the State of Nevada. 



Vegetation. 



In the northern and central portions of 

 the Great Basin the higher and better- 

 watered lands are covered with sage- 

 brush, easily recognized by its green- 



^ Mesa, a high plain or table-land. 



175 



