PRESENT FORESTS OF NORTH AMERICA 35 



fall over the Gold, Selkirk, Coeur d'Alene, Bitter Root and other 

 interior ranges. It consists largely of a few coniferous species and 

 nowhere do broad leaved deciduous trees form extensive stands 

 as they do in the Atlantic region. The latter are generally con- 

 fined to the stream valleys and are of slight importance from the 

 viewpoint of the timber industries. Towards the north the yellow 

 cedar (Chamaecy parts nootkatensis) , the Sitka spruce {Picea stichen- 

 sis) and the hemlock {Tsuga heterophylla) are the most important 

 trees. To the southward more southern forms gradually assume 

 a predominance. 



The "red fir" {Pseudotsiiga nohilis and magnifica) is the prevailing 

 tree in the vicinity of Puget Sound and southward in Washington 

 and Oregon. The "red cedar" {Thuja plicata), white fir (Abies 

 grandis), mountain hemlock {Tsuga pattoniana) and red wood 

 {Sequoia sempervirens) are also abundant and of large size. The 

 river bottoms contain heavy growths of maple, cottonwood, ash, 

 etc., and the narrower interior valleys an open growth of oak. 

 Farther south the sugar pine (Pinus lajnhertiana) , Libocedrus and 

 Chamaecyparis lawsoniana add variety and value to the Coast 

 forest, while along the Cahfornia coast between the summit of the 

 Coast Range and the ocean and extending to latitude 37°, the 

 redwood is the predominant tree. Here several species of singu- 

 larly restricted distribution are represented {Cupressus macro- 

 car pa, Pinus radiata, Abies venusta, Pinus torreyana, Tumion 

 calif ornicum, etc.). 



South of the 35th parallel the increasingly arid climate checks 

 the coast forest and the scanty woodland of the higher elevations 

 of the Coast Range farther south are of the Sierra rather than the 

 Coast type. A dense forest covers the western slopes of the Sierra 

 Nevada. The characteristic species are the sugar pine, yellow 

 pine, red fir, Abies, Libocedrus, the giant Sequoia, with valley for- 

 ests of scattered oaks. The eastern slopes are characterized by a 

 variety of large and valuable pines. 



The Interior forest extends from the sub-Arctic forest region of 

 the north southward into Mexico, and is confined to the slopes and 

 canons of the numerous mountain ranges — ^the valleys except for 



