432 CALIFORNIA FRUITS: HOW TO GROW THEM 



date in suitable interior places at the north and is at present being 

 almost wholly shipped to eastern markets before free movement 

 begins at the south. This early marketing also relieves the growers 

 of much anxiety and costly frost fighting, because the fruit, which 

 is always more susceptible to injury than the tree, is out of the 

 way before the frost period, which usually begins about Christmas, 

 is reached. 



There is in southern California, east of the mountains, a district 

 which has thus far been but scantily developed where protection 

 from ocean influences tends to early ripening of fruits. The same 

 is true of some parts of Arizona adjacent, and small quantities 

 of early fruits move westward and northward from that region. 

 That region is not in view in this discussion, for too little has 

 been accomplished in citrus lines to warrant conclusions which 

 the present confident planting in that part of the State will soon 

 supply. 



Third : Still another feature of local topography must b<j 

 mentioned as influencing citrus conditions north and south and 

 explaining why winter temperature has fallen no lower at the, 

 north than at the south. At the north the snow fields of the high 

 mountains are farther from the valleys and mesas, w r here citrus 

 fruits are grown, than they are at the south. The benches and low 

 foot-hills of the Sacramento Valley, for instance, are forty to fifty 

 miles from the high range to the east of them and there intervene 

 countless ridges of high foot-hills and small valleys, and before 

 the citrus plantations can be reached by the descending air currents 

 they are considerably warmed by rustling over so much land which 

 has been warmed by the ample winter sunshine. From many of 

 the southern citrus regions one looks almost directly upward and 

 outward upon the grand snow-clad mountains, whose crests are 

 but fifteen to twenty-five miles away. It is a splendid scenic 

 effect ripening oranges and dazzling snow fields in the same 

 glance of the eye, but it is sometimes not so grand as a porno- 

 logical proposition. 



Fourth : Another protective influence for citrus fruit trees dur- 

 ing the frosty period of December and January, is the low canopy 

 of land fog which covers the interior valley of central and northern 

 California much of the time at that season of the year and checks 

 the radiation of ground heat, which is apt to take place rapidly 

 under a clear sky. Though the nights are thus often protected 

 from frosts, the day temperature is held low, which is also of 

 account, because the citrus trees are held dormant, which is desir- 

 able, as there is no fruit to ripen. On the other hand, the higher 

 day temperature in southern California is valuable in that district 

 because the later fruit is still maturing. The winter aspects of th< 



