RAINFALL AND FROST. 35 



These are usually best attained at a degree of heat less 

 than required for fruit ripening. Again edible plants as 

 compared with trees are shallow-rooting and suffer in a 

 very hot surface soil which a tree escapes by penetration 

 of the subsoil. The growth of winter vegetables is ad- 

 vanced by abundant sunshine during the rainy season; 

 the growth of summer vegetables is promoted by cloud- 

 screen from excessive sun heat, and it is clearly refreshed 

 by summer fog. Herein, in part at least, lies the explana- 

 tion why the earliest vegetables come from interior re- 

 gions and the main crop of midseason and late vegetables 

 is to be sought in regions whose climate is modified by 

 cool coast winds, which sometimes carry fogs and always 

 temper sun action by their content of insensible aqueous 

 vapor. Some plants are especially responsive to this ac- 

 tion of coast breezes. Lima beans on the Ventura coast 

 are sometimes rescued from failure through deficient rain- 

 fall, by days of cool, misty breezes from the adjacent 

 ocean. The same is true in varying degrees of all vege- 

 tation and the fact is often of very great economic im- 

 portance to California. v 



Distribution of Rainfall. The local rainfall throughout 

 the State has of course about the same relation to local 

 gardening as it has to other farm work, but it seems 

 hardly necessary to discuss it in this place, because it is 

 possible now to secure the data from different sources. 

 Local observers almost everywhere can furnish the facts. 

 It is, however, pertinent to present a general compilation 

 which fixes approximately the date at which effective 

 rains may be expected in each main division of the State 

 and thus impart a somewhat definite notion of when the 

 natural season of growth will begin. All should be in 

 readiness beforehand to seize upon this opportunity for 

 soil working, if one is to proceed without irrigation, and 

 for the planting of seeds of hardy vegetables which will 

 withstand the local winter temperature and give the 

 earliest readiness for use under the circumstances. 



