VEGETATION AND ENVIRONMENT IN CALIFORNIA 



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however, the redwood, Sequoia sempervirens, at low altitudes 

 where it is native, shows a ver}^ special reaction to its environment 

 which is characteristic of, if not peculiar to the species. As is 

 well known, this species and others of the same genus were circum- 

 polar in distribution in former geologic ages. At the close of the 

 last ice age the species was marooned on the north coast moun- 

 tains of California where today it enjoys the dampness and the 

 fogs to which possibly its remote ancestors were accustomed. 



Fig. 2. The Valley oak, Quercus lubata, by the side of Putah Creek. This 

 specimen, and others in the vicinity of the river, are advantageously placed with 

 respect to the perennial ground water which the deeply penetrating roots attain. 



It is a moisture-loving species and its distribution, of a conse- 

 quence, is limited by the breadth of the moisture belt, which in 

 this instance is represented by the landward penetration of the 

 ocean fogs. Where an adequate summer rain is wanting the 

 dependence of the redwood on the fog is not difficult to under- 

 stand. The feathery foliage, of which any individual carries an 

 inconceivably large amount, is well adapted to condense the fog 



