Pinaceae 25 



thin with creamy- white plate-like scales; 

 leaves stout, rigid, slightly incurved, clus- 

 tered at the ends of the branches 1^-2 J inches 

 long; cones- oval or subglobose horizontal, 

 sessile, dark purple, 1^-3 inches long with 

 thickened acute scales. 



On alpine slopes and exposed ridges from 

 5000 feet elevation upward, occurring oc- 

 casionally in the Rockies, but frequent 

 throughout the Selkirks at or near the timber 

 line. 



A tree 40-80 feet high with 

 Pinus Mur- c . 1 . 



a trunk 1-3 feet in diameter, 

 tayana 



Oreg. Com. slender, strict; branches fre- 

 Black Pine, quently persistent nearly to the 

 Jack Pine. j^gg o f the stem, somewhat 



pendulous below, ascending near the top 

 of the tree, forming a pyramidal spire- 

 topped head ; bark thin, close, light orange- 

 brown with appressed scales; leaves 2 in a 

 a bundle, yellowish green, 1-3 inches long, 

 stout; cones yellowish-brown and shining 

 oval to sub-cylindric oblique at the base, often 



