THE GRASS LANDS 157 



because of the sudden dips the road takes into the great ditches 

 or arroyos which have been cut into the overgrazed range 

 by the raging torrents that follow the infrequent rains. 



Where has this soil gone that was washed out of these 

 arroyos? Into the San Juan River, silting up the channel, 

 ruining the irrigation ditches of Farmington, flowing down into 

 the Colorado and now beginning to silt up Lake Mead behind 

 Boulder Dam. 



A few miles east of the road that runs from Gallup to 

 Farmington is the divide which separates the Colorado drain' 

 age from the Rio Grande. The Rio Grande range has been 

 overgrazed for years. The soil of the range is melting away like 

 a loaf of sugar in the bottom of a teacup. As a result the lower 

 Rio Grande and the irrigation systems supplied by the Rio 

 Grande have been seriously damaged. Dangerous floods threaten 

 the land and people of the valley. 



As you drive through that country you will see mile after 

 mile of range 200 acres of which would barely support one 

 cow for one year. You will bump over washed-out roads beside 

 river beds filled with silt and boulders and lined with crumbling 

 vertical banks that are farther eaten away after each rain. Oc' 

 casionally you will come on a straggling farm community. 



Part of this washing and cutting through of the soil is a geo' 

 logical process. The streams have not yet carved out their 

 permanent channels, the soil and rock have not yet been de' 

 posited in their permanent resting place. In a state of nature 

 undisturbed by man, shifting of soil and water is a slow, almost 

 imperceptible process and it is usually accomplished without 

 any disturbance of the natural balance of soil, plants, and 

 animals. It may be called natural erosion. But man has got into 

 difficulty because he has greatly accelerated and intensified this 

 slow natural erosion. And where geological forces would have 

 taken thousands of years to do the job of moving the soil of 



