240 The Trees of Great Britain and Ireland 



Distribution 



In the colder parts of New England and Canada the hemlock is one of the 

 most characteristic trees of the virgin forest, and extends, according to Sargent, 

 from Nova Scotia and New Brunswick westward through Ontario to eastern 

 Minnesota, southwards through Delaware, southern Michigan, and central Wisconsin, 

 and along the Appalachian Mountains to north-western Alabama. He says^ that it 

 attains its largest size in the south, in the mountain valleys of North Carolina and 

 Tennessee, and gives its size as usually 60 or 70 and occasionally 100 feet in height, 

 with a trunk 2 to 4 feet in diameter; but Pinchot and Ashe {loc. cit. p. 134) give no 

 feet with a diameter of 6 feet as its extreme size, with a beautiful picture of it 

 (pi. xix.). When, however, I was at Ottawa in September 1904 I visited, in 

 company with Mr. James M. Macoun of the Geological Survey, a forest near 

 Chelsea, in the Gatineau valley, where several hemlocks of nearly 100 feet were 

 standing, mixed with birches, maples, and other hardwoods, and found a fallen tree 

 which must have been at least 125 feet, and perhaps 135 feet long, though the top 

 was too rotten to follow it out to the end. Mr. Macoun, however, said he had never 

 seen one so large before. 



It often grows on rocky ridges, where it forms dense groves on the north 

 side, and loves the steep banks of river gorges. Henry visited in 1906 Pisgah 

 Mountain, near Hinsdale, in New Hampshire, where there remain on the estate of 

 Mr. Ansell Dickinson about 700 acres of virgin forest. This mainly consists of a 

 mixture of hemlock and hardwoods, with white pine occurring here and there singly 

 and in small groups ; though on one or two areas of a few acres the white pine and 

 hemlock form a pure coniferous stand. The largest hemlock seen measured 113 

 feet by 7 feet 10 inches, with a clean stem of only 30 feet, being much branched 

 though densely crowded by other trees. A great many small hemlocks throughout 

 the forest formed an undergrowth, and had been suppressed in growth, one which 

 was f inch in diameter and 10 feet high showing 65 annual rings. 



In the Arnold Arboretum, near Boston, is a fine natural grove of this tree, 

 called Hemlock Hill, which gives a very good idea of its normal growth in New 

 England. The average height here is 60 to 70 feet by 3 to 4 feet, and the best that I 

 measured at the bottom of the hill was 80 feet by 4 feet 6 inches. These trees were 

 rather crowded, and had clean boles for 1 5 to 30 feet up. 



The growth of the tree is very slow, and Sargent says that the specimen of its 

 timber in the Jessup Collection in the American Museum of Natural History at 

 New York (which is the most complete that has ever been formed of the woods of 

 any country) is only 13I- inches in diameter inside the bark, though it shows 164 

 annual rings, of which the sapwood, 2 inches thick, has twenty-nine. 



It seeds freely, but the seedlings do not germinate well in the open or on land 

 which has been recently burned over, and seem to succeed best on a mossy stump or 

 fallen log, where they must often remain eight to ten years before their roots reach 

 the earth. According to Sargent they are only three or four inches high at four 

 years old, under favourable conditions, and are easily destroyed. 



