116 C0NIFER2E. Pinus. 



Texas, high mountain ranges of Utah, Nevada, and northern Arizona, 

 Inyo Mountains and Mount Silliman, California. 



A tree 15 to 18 metres in height, with a trunk 0.G0 to 1.20 metres in 

 diameter; dry, gravelly slopes and ridges between 4,000 and 10,000 feet 

 elevation ; common along the eastern slopes of the Rocky Mountains of 

 northern Montana, forming open, scattered forests, and the prevailing forest 

 tree ; in central Nevada the most valuable timber tree of the region. 



Wood light, soft, close-grained, compact ; bands of small summer cells 

 narrow, not conspicuous ; resin passages numerous, large ; medullary rays 

 numerous, conspicuous ; color light clear yellow, turning red with expo- 

 sure, the sap-wood nearly white ; in northern Montana, Nevada and 

 Utah sometimes sawed into inferior lumber and used in construction 

 and for various domestic purposes. 



351. Pirms albicaulis, Engelm. 



Coast Ranges of British Columbia, south along the Cascade and Blue 

 Mountains of Washington and Oregon ; California, — Scott Mountains, 

 Mount Shasta, and along the high peaks of the Sierra Nevada to Mount 

 San Bernardino ; extending east along the high ranges of northern 'W ash- 

 ington to the eastern slope of the Rocky Mountains of northern Montana. 



A small alpine tree, 6 to 12 metres in height, with a trunk rarely 0.60 

 metre in diameter, or at its highest elevation reduced to a low, prostrate 

 shrub; dry. gravelly ridges at the extreme limit of tree growth, reaching 

 in the San Bernardino Mountains an elevation of 10,500 feet. 



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

 small summer cells thin, not conspicuous; resin passages uumerous, not 

 large ; medullary rays numerous, obscure ; color light brown, the sap-wood 

 nearly white. 



352. Pinus reflexa, Engelm. 

 White Pine. 



High mountains of southwestern New Mexico to the Santa Rita and 

 Santa Catalina Mountains. Arizona. 



A tree 24 to 30 metres in height, with a trunk sometimes exceeding 

 0.00 metre in diameter; rocky ridges and slopes of almost inaccessible 

 canons between 6,000 and 8.000 feet elevation. 



Wood light, hard, not strong, close-grained, compact ; bands of small 

 summer cells thin, resinous, not conspicuous ; resin passages few, large; 

 medullary rays numerous, obscure ; color light red, the sap-wood nearly 

 white. 



353. Pinus Parryana, Engelm. 

 Pinon. Nut Pine. 



California, — Larkin's Station, 20 miles southeast of Campo, San 

 Diego County, and in lower California. 



