56 DRY LAND FARMING 



the state does the rainfall exceed 15 inches. In a much 

 larger area in the central part of the same it runs from 

 8 to 12 inches. In practically all the other portions of 

 the state it is less than 10 inches. In not less than half 

 the entire area the conditions would seem to indicate 

 aridity in the absence of irrigating waters. This state 

 has the lowest average precipitation of all the states in 

 the Union. 



In Arizona the average annual precipitation is 12.15 

 inches, the maximum 24.9 and the minimum 3.1, viz., at 

 Yuma. In portions of say five counties in the central 

 part of the state, the rainfall is 15 inches and upwards. 

 In the southwestern part of the state it is 5 inches and 

 less. In nearly all the other portions it is from 5 to 15 

 inches. Arizona has a large area of arid land. 



In California the average annual precipitation is 21 

 inches, the maximum 88.8 and the minimum 1.1, viz., at 

 Ogilby, in Imperial county. If a line were run straight 

 across the state so as to cut off north from it about two- 

 fifths of the same, with the exception of a very small por- 

 tion in the extreme northeastern corner, that portion 

 would represent in nearly all instances an exceedingly 

 heavy rainfall. Nearly half of the remaining area ly- 

 ing along the Pacific has a rainfall of 10 to 20 inches, and 

 the other portion from 10 inches down to virually no 

 rainfall. A very considerable portion of southern Cali- 

 fornia is arid. 



In Oregon the average annual precipitation is 42.8 

 inches, the maximum 117.0 and the minimum 8.6. West 

 of the Cascades the precipitation is very heavy. In the 

 northeastern counties, it is 15 inches and upwards. In all 

 other portions it is below 15 inches, and in nearly all 

 parts more than 10. 



In Washington the average annual precipitation is 

 36.15 inches, the maximum 127 and the minimum 6.5. 

 Westward from a line running down through the center 



