Pinus. 



CONIFERS. 119 



a trunk 0.23 to 0.33 metre in diameter ; crests of sandy bluffs immediately 

 upon the sea-coast ; very local and fast disappearing. 



Wood li'dit, soft, not strong, brittle, rather close-grained, compact; 

 bands of small summer cells broad, resinous, conspicuous ; resin passages 

 small, few ; medullary rays numerous, obscure ; color light red, the sap- 

 wood yellow or nearly white ; locally used for fuel. 



360. Pinus Arizonica, Engelm. 

 Yellow Pine. 



Santa Rita Mountains, Santa Catalina Mountains, and probably upon 

 other ranges of southern Arizona. 



A tree 24 to 30 metres in height, with a trunk 0.G0 to 0.90 metre in 

 diameter ; high rocky ridges between 6,000 and 8,000 feet elevation, and 

 forming extensive forests near the summits of the Santa Catalina 

 Mountains. 



Wood light, soft, not strong, rather brittle, close-grained, compact; 

 bands of small summer cells broad, very resinous, conspicuous ; resin pas- 

 sages numerous, large ; medullary rays thin, obscure ; color light red or 

 often yellow, the sap-wood lighter yellow or white ; sometimes sawed into 

 inferior lumber. 



361. Pinus ponderosa, Dougl. 

 Yellow Pine. Bull Pine. 



Interior of British Columbia, south of latitude 51°, south and east 

 along the mountain ranges of the Pacific Region to Mexico, the Black 

 Hills of Dakota, Colorado, and western Texas ; not detected in central or 

 southern Nevada. 



A large tree, 61 to 91 metres in height, with a trunk 3.60 to 4.57 

 metres in diameter, or throughout the Rocky Mountain region much 

 smaller, rarely exceeding 30 metres in height (var. scopulorum) ; dry, 

 rocky ridges and prairies, or in northern California rarely in cold, wet 

 swamps, reaching its greatest development along the western slope of the 

 Sierras of northern and central California ; in western Washington and 

 Oregon, rare and local ; next to Pseudolsuya Douglasii the most generally 

 distributed and valuable timber tree of the Pacific forests, furnishing the 

 principal lumber of eastern Washington and Oregon, western Montana, 

 Idaho, the Black Hills of Dakota, western Texas, New Mexico, and 

 Arizona. 



Wood varying greatly in quality and value, heavy, hard, strong, brittle, 

 not coarse-grained nor durable, compact ; bands of small summer cells broad 

 or narrow, very resinous, conspicuous ; resin passages few, small ; medul- 

 lary rays numerous, obscure ; color light red, the very thick sap-wood 

 almost white ; largely manufactured into lumber, and used for railway- 

 ties, fuel, etc. 



