Handbook of Trees of the Xortuekn States and Canada. 



The Yellow Pine of tlic Rocky Mountain 

 region is usually a nu'diuui size tree of from 

 50-70 ft. in height with trunk from 1-2 ft. 

 in diameter, but where conditions are par- 

 ticularly favorable attains tlie heiglit of 100 

 to 125 ft., with trunk 3-4 ft. in tiiainetcr. The 

 bark of the younger trunks is dark and fis- 

 sured into rather firm scaly ridges but these 

 flake ofi' with age and the bark of old trunks 

 is more of a cinnamon-red color and broken 

 into large scaly plates. It develops a distinct 

 pyramidal head at first and by the gradual 

 lengthening of the lateral branches finally a 

 broad rounded top. It occupies well-drained 

 uplands and mountain slopes, being particu- 

 larly abundant in the Black Hills of Dakota, in 

 northwestern Nebraska and on the mountains 

 of Colorado at altitudes ranging from six to 

 ten thousand feet. On the Colorado plateau 

 of northern Arizona and New Mexico it forms 

 vast and valuable forests. 



Its peculiarity in having leaves both in 

 clusters of two and three is exceptional to the 

 usual habit of the Pines. 



The wood is rather hard, heavy and strong 

 and useful for lumber for general construc- 

 tion purposes, interior finishing, etc. 



Leaves lioth in clusters of 2 and .'?, Z-6 in. lonar, 

 rigid, with sheaths at first close and about % in. 

 long but finally loose and shorter, stomatiferous 

 all sides and containins 2 fibro-vascular bundles 

 and 2-") resin-ducts within the iiarenchyma. 

 Flowers: staminate about 1 in. lon-jr. Fruit: 

 cones 2-4 in. Ions;, ovoid, deciduous above the 

 lowest basal scales, somewhat ol>li(iue with scales 

 tliick(>ned at apex and covered with slender 

 sti'ongly recurved prickles : seed i/4 in. long with 

 ample wing broadest in the center. 



1. Syn. P. Scopulorum Lem. 



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