A Barren Land

The western edge of Arizona, along with the southeast part of California,  and southern Nevada, is the driest part of the United States. This is an extremely harsh desert with an average of only 3 to 4 inches of rain per year. In fact, there is a portion of Death Valley, in California, that only averages 1.6 inches of rain per year! Most of the western edge of Arizona is a nearly naked landscape, only occupied by the hardiest, most drought-resistant plants. In fact, Yuma, in southwestern Arizona, only averages 2.88 inches of rainfall per year and San Luis, 25 miles south of Yuma, on the border with Mexico, probably averages less than that, but I have not found statistics for that town. I am guessing San Luis averages about 2.7 inches of rain per year.
  Yuma County is the second driest county in the United States.  The eastern edge of  county, the "wettest" part, still only gets about 6 inches per year. The only county that is drier is its neighbor to the west, Imperial County, in California.
  Even the mountains of this area support very little in the way of vegetation. Their slopes, with a few exceptions such as Palm Canyon, are almost completely barren and, in many places, they are completely barren. 
  Yuma County covers an area of 5,518 square miles, so it is a big county by the standards of most states, but not by Arizona standards. Arizona, the nation's sixth largest state, only has 15 counties. The counties in Arizona are way too big, for the most part, and many of them need to be divided into smaller units.   
  Before  1983, Yuma County was nearly twice the size that it is now. The northern 45% of the county split off and formed La Paz County. This new county became official on January 1, 1983. I will talk more in depth about La Paz County in the future. For now, my topic is Yuma County.