are the Engelmann spruce, limber pine, alpine 

 fir, arctic willow, black birch, and quaking 

 aspen. 



A few timber-line trees live a thousand years, 

 but half this time is a ripe old age for most 

 timber-line veterans. The age of these trees can- 

 not be judged by their size, nor by general ap- 

 pearance. There may be centuries of difference 

 in the ages of two arm-in-arm trees of similar 

 size. I examined two trees that were growing 

 within a few yards of each other in the shelter 

 of a crag. One was fourteen feet high and six- 

 teen inches in diameter, and had three hundred 

 and thirty-seven annual rings. The other was 

 seven feet high and five inches in diameter, and 

 had lived four hundred and ninety- two years! 



One autumn a grizzly I was following — to 

 learn his bill-of-fare — tore up a number of 

 dwarfed trees at timber-line while digging out 

 a woodchuck and some chipmunks. A number 

 of the smaller trees I carried home for careful 

 examination. One of these was a black birch 

 with a trunk nine-tenths of an inch in diameter, 

 a height of fifteen inches, and a limb-spread of 



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