608 



AMERICAN FORESTRY 



hundred I'ect away. The yoiiiif^sters reminded me of 

 boys who go their own way in life, feeling satisfied 

 that the old man doesn't know what he's talking about. 

 Contrary to a statement made in a very reliable 

 natural history, the muskrats and the beavers lived 

 entirely at peace with each other, one paying no atten- 

 tion to the other. In the house below the high bank 

 beavers and rats also lived together peacefully, but in 

 both cases the rats generally used small entrances 

 close to shore, and I think they lived in a small cavity 

 in the bank by themselves. In a third Inouse musk- 

 rats were also present, but I did not learn on what 



WHKRF. BEAVKR THRIVED 



Scene in a popl'ii' grove in winter after the beavers have cut down and 

 pickled their supply of brush and food poles. This is in the Itasca Forest, 

 Minnesota. 



terms thej' lived with their larger relatives. At Poplar 

 Point rats fed almost entirely among the lilies and 

 other plants in a little bay in wliicli the beaver house 

 was located, and seldom traveled more than a few rods 

 from home, but they also ate the foliage and bark of 

 poplar on the beaver house. They generally appeared 

 about half an hour l)efore the bea\ers came out. The 

 beavers, on the other hand, all swam to the feeding 

 ground a quarter of a mile away, where three kinds 

 of water lilies grew in abundance and where they had 

 also done much fresh cutting among the poplars on 

 shore. 



The most interesting obser\atioii 1 made on the 

 last evening T could sjjcnd on my jilatform at Poplar 

 Point. Beavers began to show themselves very freely 

 about seven o'clock ; once I saw four or five at the 

 same moment. About 7 :45 a beaver, a yearling to 

 judge by his size, came very carefully out of the 

 house. He hesitated a minute, and then, almost direct- 

 ly below me walked slowly u]) to a green poplar I 

 had cut the night before anrl with a few lateral move- 

 ments of his head cut off a twig the thickness of a 



man's thumb. The next moment, seizing the butt 

 with his mouth or fore feet — I could not make sure 

 which — he swung the leafy branch over his left 

 shoulder from which it slid off almost immediately ; 

 he then seized it with his teeth, dragged it into the 

 water, dived with it and took it into the house. No 

 sooner had he entered than the babies of the family- 

 set up a lively whining in appreciation, as I imagined, 

 of the prize the big brother had brought in. This was 

 the most intimate glimpse I had of the beavers' home 

 life and was the only time I saw a beaver on land. 



I noted that the bea\ers never ti inched the other 

 liii]tlar to])s I had dropped almost on their house and 

 they had practically done no cutting in the poplar 

 grove near their house. They nearly alway:. left the 

 house at the same exit and, after the old ones had 

 scouted along the shore, both parents and yearlings 

 often swam directly to their feeding place about a 

 (|uarter of a mile to the west. Several times I watched 

 one swim as straight as the crow flies with a speed 

 of about one hundred yards a minute. 



The most remarkable lieaxer structures are the 

 dams, built across small streams and creating the 

 well-known beaver jionds. Dams from a hundred to 

 three hundred feet long are common, and in rare in 

 stances a beaver dam may reach a quarter of a mile in 

 length. The height of a dam varies from a few inches 

 near the ends to five or six feet in the highest places. 

 It is built of dead brush and sticks held together by 

 mud scooped and dug up immediately above the dam. 

 The beavers had cut no standing trees for any of the 

 dams I had seen. No stakes are driven into the ground 

 and no large rocks used to hold down the brush. The 

 dams are not given any artistic finish, and look as if 

 a lot of boys had built them : but by being kept in 

 repair they hold the water in the pond. The amount 

 of work expended in their construction is very large, 

 considering that a beaver averages only about thirty 

 pounds in weight and has only his small fore feet to 

 use as hands and his four chisel-like teeth for cutting 

 brush, trees and sticks, or for seizing his material 

 when he drags or floats it to his house or dam. I esti- 

 mated that duplicating a certain three hundred foot 

 dam would take a man equii)i)ed with pick, ax and 

 shovel about four weeks. 



The streams which the beavers dam up to make 

 their jionds vary in size from insignificant rills to 

 streams large enough to carry a row-boat. In the late 

 fall of 1913 they built two dams across the Mississippi 

 where the stream issues from Lake Itasca. A beaver 

 pond is frequently a (piarter of a mile long and covers 

 an area of from five to ten acres, but ponds have been 

 observed covering from fifty to sixty acres. None of 

 the ponds in the Itasca Reserve are over ten years old, 

 but in the early days a well located beaver pond may 

 have been occupied for a century or longer, although 

 the life time of an individual beaver probably does not 



