Pinus. 



CONIFERS. 117 



A small tree, 6 to 9 metres in height, with a trunk 0.30 to 0.45 metre 

 in diameter ; very rare within the limits of the United States ; south of 

 the boundary forming in lower California extensive open forests upon 

 high ridges and slopes. 



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

 thin, not conspicuous ; resin passages very numerous, large, conspicuous ; 

 medullary rays numerous, obscure; color light brown or yellow, the 

 sap-wood much lighter, nearly white. 



The large seeds edible. 



354. Pinus cenibroides, Zucc. 

 Pirion. Nut Pine. 



Santa Catalina Mountains, Arizona ; in northern Mexico. 



A small tree, in Arizona 6 to 7 metres in height, with a trunk hardly 

 exceeding 0.30 metre in diameter ; dry ridges and slopes at 3,500 feet 

 elevation. 



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

 cells thin, not conspicuous ; resin passages few, small ; medullary rays 

 numerous, obscure ; color light clear yellow, the sap-wood nearly white. 



The seeds edible. 



355. Pinus edulis, Engelm. 

 Pinon. Nut Pine. 



Eastern base of Pike's Peak, Colorado, south through New Mexico 

 to the mountains of western Texas. 



A small tree, 6 to 9 metres in height, with a trunk 0.30 to 0.90 

 metre in diameter ; dry slopes, generally on lime or sandstone, reaching 

 in Colorado an elevation of 9,000 feet. 



Wood light, soft, not strong, brittle, close-grained, compact, durable in 

 contact with the soil ; bands of small summer cells thin, not conspicuous ; 

 resin passages few, small ; medullary rays numerous, obscure ; color light 

 brown, the sap-wood nearly white ; largely used for fuel, charcoal, fen- 

 cing, etc., and in western Texas occasionally manufactured into inferior 

 lumber. 



The large seeds edible. 



356. Pinus monophylla, Torr. & Frem. 

 Pinon. Nut Pine. 



Western base of the Wahsatch Mountains, Utah, to the eastern foot-hills 

 of the California Sierras, south along the mountain ranges of the Great 

 Basin to the San Francisco Mountains of eastern Arizona. 



A small, bushy tree, 4 to 6 metres in height, with a trunk sometimes 

 1 metre in diameter ; dry, gravelly skmes between 3,000 and 6,000 feet 

 elevation. 



