an Engelmann spruce. The majority of beaver 

 burrows are about two thirds the size of this one. 



One November I examined more than a score 

 of beaver colonies. There was no snow, but re- 

 cent cold had covered the pond with ice and 

 solidified the miry surroundings. Over the frozen 

 surface I moved easily about and made many 

 measurements. One of these colonies was a fairly 

 typical one. The colony was on a swift-running 

 stream that came down from the snowy heights, 

 three miles distant. The top of Long's Peak and 

 Mt. Meeker looked down upon the scene. The 

 altitude of this colony was about nine thousand 

 feet. The ponds were in part surrounded by semi- 

 boggy willow flats, with here and there a high 

 point or a stretch of bank that was covered with 

 aspens. The tops of a few huge boulders thrust 

 up through the water. All around stood guard a 

 tall, dark forest of lodge-pole pines. These swept 

 up the mountainside, where they were displaced 

 by a growth of Engelmann spruce which reached 

 up to timber-line on the heights above. 



This colony had a number of ponds, with a 

 few short canals extending outward from them. 

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