Like Rainfalls not Equally Productive 101 



small as 7 or 8 inches, and large yields when it reaches 

 12 to 15 inches, provided it has a suitable distribu- 

 tion. 



LIKE AMOUNTS OF RAINFALL NOT EQUALLY 

 PRODUCTIVE 



In the United States west of the 97th meridian, 

 where the rainfall is notably deficient, except on the 

 west side of the Cascade range in Oregon and Washing- 

 ton, there are a large number of areas in which an effort 

 has been made to grow crops of one kind or another 

 without irrigation, and in considerable areas with 

 marked success, as in the San Joaquin- Sacramento val- 

 ley, in California, and in eastern Washington and 

 Oregon, to which reference has just been made. In the 

 sketch map, Fig. 20, prepared by Newell, the areas in 

 which "dry farming," or farming without irrigation, 

 has been practiced with greater or less success, are 

 represented in black. It will be seen that this map 

 shows a long, continuous area, just west of the 97th 

 meridian, another one in California, and a third in 

 Washington, besides very many smaller ones. These 

 three larger areas receive very nearly the same amounts 

 of rainfall for the year, but the distribution of it in time 

 is very different. In California the rain all falls in [the 

 six months, November to April, inclusive ; in Washing- 

 ton it is from October to May, inclusive, while in the 

 97th meridian region, much the larger part of the rain 

 falls during the months between April and September. 

 The eastern region, therefore, has its moisture well dis- 



