THE NORTH TEMPERATE ZONE 



145 



Marshes are not especially characteristic of the Californian 

 coast, but in the delta lands of the Sacramento and San Joaquin, 

 are extensive tracts of marsh-land, through which the railway 

 between San Francisco and Sacramento passes. These "Tule 

 marshes" are largely almost pure associations of bulrushes (Scirpus 



Fig. 40. A 



A. Coniferous forest, Mt. Shasta region. 



B. Azalea (A. occidcntalis) . 



spp.). together with cat-tails and other characteristic marsh 

 plants in the more open places. 



The accumulation of vegetable matter builds up islands of 

 peaty humus soil, which support many plants, some quite charac- 

 teristic of the marsh region. When drained, the delta lands are 

 extremely productive, and of great value. 



Extending from the Oregon line to southern California, the 

 lofty range of the Sierra Nevada forms California's eastern bound- 



