650 



THE NATIONAL GEOGRAPHIC MAGAZINE 



Average Weather Conditions at Redlands, 

 California, i8gy-igog 



Mean , ^^^n Average 



January 43 63 40 52 2.64 



February ... 48 66 42 54 2 . 37 



M-arch 42 70 43 56 3.08 



April 32 74 47 60 1.85 



May 44 76 50 63 1.76 



June 36 88 54 71 .17 



July 26 95 58 77 .01 



August 27 95 59 77 .16 



September.. 28 90 56 73 .27 



October.... 33 81 50 66 .74 



November.. 35 72 45 58 1.04 



December... 32 67 41 54 .95 



Total for the year 15 .04 



Only 16 per cent of the days are 

 cloudy and rainy. The rainy days aver- 

 age but 15 in a year. During all these 

 years the temperature has exceeded 100 

 degrees in July, August, and September 

 on an average of only fifteen times a 

 year, and has fallen below 32 degrees on 

 an average of less than three times a 

 year. The wet bulb thermometer is 

 usually less than 20 degrees below that 

 of the dry bulb. The lowest recorded 

 temperature of 25 degrees was only 

 reached twice. January, February, and 

 March are the wettest months. 



The valley of southern California is 

 protected from the cold northern winds 

 of winter by high mountain ranges, 

 while to the south it is open to the Pa- 

 cific. Owing to the peculiar configura- 

 tion of the coast the cold California cur- 

 rent from the north is deflected west near 

 Point Conception, and hence the south- 

 ern California shores have waters 

 warmer by about 10 degrees than those 

 to the north. Then, too, the mountain 

 barriers afford protection from the heat 

 of the dry hot deserts to the east, and 

 they cause precipitation which affords 

 running water in fair volume in many 

 streams. These mountains are so high 

 that the winter snows linger on them far 

 into the spring, when southern Califor- 

 nia is gay with its innumerable flowers. 



F^RUIT OF SOUTHERN CALIFORNIA 



This beneficent climate is responsible 

 for the giant industry of fruit growing 



which has made California famous over 

 the globe. California furnishes the major 

 part of the very large amount of oranges 

 and other citrus fruits consumed in the 

 United States, and this business has been 

 the potent cause in the development of 

 southern California. Ever since the 

 early days of settlement it was known 

 that climate and soil were favorable, but 

 it was not until about 20 years ago that 

 the great orchards were developed. The 

 splendid success of the business led many 

 to engage in it, until finally most of the 

 available land came under cultivation. 



There are two important natural limi- 

 tations to the extension of orange cul- 

 ture — one is lack of water; the other is 

 frost. Water for irrigation is a neces- 

 sity, and as the available supply is lim- 

 ited only a certain acreage can be utilized. 



At an early period all the surface 

 waters were taken out in ditches, and 

 then the underground waters were tapped 

 by numerous wells. Storage dams have 

 helped to conserve the surface waters 

 somewhat, but the artesian supplies have 

 been drawn on beyond their capacity for 

 replenishment, and they are steadily 

 diminishing in some districts of large 

 extent. 



A few years ago hydrologists of the 

 U. S. Geological Survey made a careful 

 investigation of the amount of under- 

 ground waters available, and placed the 

 data on maps and diagrams which will 

 afford a definite basis for the water con- 

 servation. There are frequent lawsuits 

 concerning underground waters, most of 

 them brought by the man with the little 

 pump when he finds that the company 

 with the large pump is drawing away his 

 water. There are about 3,000 flowing 

 wells and 7,000 pump wells now supply- 

 ing water for irrigation, with an esti- 

 mated total volume of about 500 second 

 feet. 



The area of agricultural land in the 

 fruit district is about one million acres, 

 of which about one-fourth have water 

 for irrigation and are cultivated. The 

 remaining three-quarters is without 

 water. The new water supply for Los 

 Angeles will be about 260 million gallons 



