26 Pinaceae 



clustered f 2 inches long, with slightly con- 

 cave scales with slender deciduous prickles. 



The most abundant tree at the lower alti- 

 tudes throughout the Rockies, frequently 

 covering vast tracts, and rising on the moun- 

 tain sides to 6000 feet or occasionally higher. 



A tree usually 40-50 feet high 

 Lyallii with a diameter of 18-20 inches 



Parl. and remote, elongated, tough, 



Lyall's persistent, nearly black branches, 



with prominent winter buds with 

 conspicuous long white matted hairs fringing 

 the margins of their scales and often nearly 

 concealing the buds; bark on the old trunks 

 J to | of an inch thick, pale gray, divided 

 into shallow irregular plates; leaves many 

 in a cluster, 4-angled, slender, blue-green 

 i-ij inches long; young cones showy with 

 dark red or yellow-green scales and dark 

 purple bracts; when mature, ovate iJ-2 

 inches long with reddish-purple scales and 

 long tipped dark purple bracts. 



An alpine tree occurring with more or 



