THE HEMLOCK, FIR, AND LARCH. 275 



Mountains many of the trees are destroyed solely for 

 their bark, although the timber is very valuable for 

 house-framing and for rough hoarding; much of it, 

 though, is subject to a Haw called "wind shake," a 

 perpendicular splitting of the wood caused by winter 

 storms which bend and "shake' the stems. The 

 wood is rather white, and faintly tinged with buff 

 or pink; its grain is coarse, twisted, and unfit for 

 interior finish. 



The mountain hemlock (Txuga Ca/rolvrda/ruC\ is 

 a species so similar to the foregoing that it is not 

 an easy matter to discriminate between them, h 

 is rather rare, anyway, growing wild only in the 

 higher Alleghany Mountains. A small specimen in 

 the Arnold Arboretum, the only one I have seen, 

 differs from the common hemlock in its larger needle 

 more thickly distributed over the branchlet, and its 

 larger cone with more spreading scale-. This tree 

 rarely grows over 30 feet high. 



Balsam Fir. The balsam fir is the much-esteemed 



Abies balsamea. " Christmas tree," whose anmiatie 



perfume is a sufficient means for its identification. 

 This is the tree, in fact, which furnishes the needles 

 for "pine pillows." It can not he reasonably con- 

 fused with the spruce for several reasons. It- needle 

 is about three quarters of an inch long (rarely it 

 measures a full inch), dark blue-green above and 



