SOIL SUEVEY OF THE RED BLUFF AREA, CALIFORNIA. 



11 



Bluff the last killing; frost occurs in spring at an average date of 

 March 15; the first in the fall at an average date of November 25. 

 The following table gives monthly and annual mean temperatures for 

 several stations : 



Monthhi (itid annual mean temperatures. 



Red Bluff, 

 1878-1909. 



Chico, 

 1870-1900. 



Sacra- 

 mento, 

 1853-1900. 



Fresno, 



1888-1900. 



January 



February.. 



March 



April 



May 



June 



July 



August 



September . 



October 



November . 

 December. . 



Mean 



F. 

 45. 

 49. 

 53. 

 59. 

 6G. 

 74. 

 81. 

 SO. 

 73. 

 G3. 

 53. 

 46. 



F. 



G2. 



46.9 

 50.3 

 55.6 

 61.6 



68.4 

 77.1 

 83.9 

 81.5 

 74.6 

 64.6 

 53.8 

 47.5 



'F. 



47.5 

 51.2 

 65.0 

 58.5 

 02.7 

 70.3 

 73.1 

 70.3 

 69.8 

 61.3 

 54.5 

 45.4 



45.3 

 50.2 

 54.4 

 60.8 

 67.4 

 74.1 

 82.1 

 81.0 

 73.8 

 64.2 

 54.6 

 47.0 



63.8 



60.0 



63.0 



At Red Bluff during the period from 187T to 1009 there was an 

 average of 82 days per j'^ear when the thermometer did not fall below 

 90°. There was no day when it did not rise above 32° F. The abso- 

 lute maximum temperatures usually occur during the months of 

 July and August, high readings of 109° to 112° F. being of frequent 

 occurrence. An absolute maximum of 115° was reached at the Red 

 Bluff' station during the summer of 1902. The highest temperature 

 recorded at the Chico station has been 117° F. As is usual with the 

 high temperatures of semiarid regions, the oppressiveness is dimin- 

 ished by the extreme dryness of the air. The nights are not usually 

 oppressive. The absolute minimum temperatures are usually re- 

 corded during the months of December, January, and February. 

 Low^ temperatures of 24° to 28° F. are the rule. In 1885 the low tem- 

 perature at Red Bluff was 33°. An absolute minimum of 18° was 

 reached in January, 1888. The lowest temperature recorded at the 

 Chico station is also 18° F. 



The climate of the Red Bluff' area is remarkably salubrious. As 

 with the major part of the great valley, it is very well suited to 

 fruit culture, the absence of rains during the summer allowing the 

 curing of dried fruits and hay to proceed without loss. Frosts do 

 little damage to fruits. The uncultivated sections have a rather 

 bleak appearance during the hot summer months, but the winter 

 months present a marked contrast. At those times wdien the eastern 

 humid sections are barren of green growth the w^inter rains of this 



