The Vegetation of North America 



335 



cisco Bay, the forest is composed of redwoods, the tallest of all 

 conifers. 



From this point southward the Coast Ranges are dominated by 

 vegetation consisting of scrub oaks, hardleafed shrubs, and xero- 

 phytic grasses — collectively known as chaparral. The chapar- 

 ral also forms a belt surrounding the central valley of California 

 and the lower elevations of the southern California mountains. 

 This is a region of winter rainfall and hot, dry summers. 



Inland from southern Oregon and south along the Sierra 

 Nevadas is an extensive forest of Western yellow pine, with 

 Douglas fir, incense cedar, and sugar pine intermingled. In 

 California this forest is restricted to the moist slopes above 1500 

 feet in the north and above 3000 feet in the south. Above the 

 pine forest is a belt of firs and hemlock, and at the timber line 

 the white-barked pine occurs. Between the pine belt and the 

 desert is a belt of oak and digger pine, and at lower levels an 

 extensive growth of chaparral. On rolling uplands between the 

 large canyons on the western slope of the Sierras occur groves of 

 the celebrated '' Big Trees." At timber line here and elsewhere 



W. S. Cooper 



Fig. 207. Foothills and valley land in Arizona covered with grass and oak brush, affording 



grazing range for goats. 



