428 GEOLOGICAL SURVEY OF CANADA. 



rather low rocky woods, but it is found in fence cornei-s in all clearings. 

 Around Ottawa it seldom attains the height of 60 feet, but westward 

 it becomes larger and on the Niagara peninsula is much taller and 

 increases considerably in diameter. It is easily distinguished from its 

 allies by its wide branching habit. 



(194Y.) U. Americana, Linn. American Elm. 



U. Americana, var. pendvla, Ait. Pursh, Fl. I., 200. 



The White or American Elm delights in low, humid and rich soils, 

 and the better the soil, the larger the tree. This tree has a very wide 

 distribution, being found on the low intervale lands of Cape Breton, 

 Nova Scotia, and New Brunswick. In Quebec it becomes more plen- 

 tiful, and in the valley of the St. Lawrence and throughout Ontario it 

 is very abundant. West of Toronto and in the whole district border- 

 ing on Lakes Erie and Huron it grows to an enormous size, attaining 

 a greater height and girth than any other Canadian tree, except the 

 pine. West of Lake Huron, it retires again to the low alluvial soil in 

 river bottoms, and is found in the valley of the Eed Eiver from Pem- 

 bina to Lake Winnipeg. It ascends the Assiniboine to its source. 

 It passes by the way of lakes Manitoba and Winnipegoosis to Eed Deer 

 Eiver, which flows into the last named lake, where it ceases to grow in 

 Lat. 53°. (Macoun.) On the Saskatchewan, it ascends to near Cum- 

 berland House in Lat. 54° 30', where Mi-. A. S. Cochrane observed a 

 number of good sized trees. It occurs at the head waters of all the 

 principal branches of the Moose Eiver, and on one of them, the 

 Missinaibi, found an outlier within 120 miles of James Bay. On 

 the Kenogami it extends to a point about half-way from Long Lake 

 to the Albany. (B. Bell.) At Lake Waswanapy, North-east Terri- 

 tory. (J. M. Macoun.) 



(1948.) U. racemosa, Thomas. Eock Elm. 



U- Americana, Planchon. De Candolle, Prodr. XVII., 155, in part 

 Eathar rare in the Eastern Townships, Quebec, and extending west- 

 ward throughout Ontario in the limestone areas. This tree seems to 

 be confined to dry gi-avelly soils and is usually associated with sugar 

 maple in such localities. It was formerly very common and large 

 quantities were cut down, squared and exported, but owing to the 

 destruction of maple woods it is now found chiefly as second growth 

 along roadsides and borders of fields. 



