Lake Superior, but we are now fairly familiar with it in the country 

 around that lake and eastward of it to the Atlantic Ocean. The 

 eastern provinces are within the region of the tree forests, whilst a 

 very large part of Manitoba and an immense section of the terri- 

 tory between that province and the Rocky Mountains is more or 

 less open prairie. The vast country commencing with Labrador 

 and thence skirting Lake St. John, Hudson Bay and the north shores 

 of Lake Nipigon, onwards to the Saskatchewan and Peace River 

 northward, forms the zone of the balsam, poplar, white birch, aspen 

 and tamarac. South of this in the Provinces of Quebec and 

 Ontario are the zones of the pines and the beech the beech being 

 chiefly limited to the region south of a line drawn from the outlet 

 of Lake Superior to Quebec. In that part of the peninsula of 

 Ontario lying west of the Niagara River is an outlier of another 

 zone, represented there by the walnut, buttonwood, tulip tree, 

 sassafras and the chestnut, and by an increasing abundance of 

 white, red and other oaks. 



There are various causes influencing the range of vegetation in 

 the Dominion, but in Ontario and Quebec the northern limits of 

 trees are largely circumscribed by the physical condition of the 

 country as well as by the climate. The height of land or water- 

 shed from which the rivers flow on the one side to Hudson Bay, 

 and on the other to the great lakes and the St. Lawrence, has a 

 very tortuous course, and beyond it very few species of trees range 

 northward. The country on either side of this watershed for some 

 distance is more or less mountainous. To the northward of Lake 

 St. John the whole country is very broken, whilst extensive cold 

 swamps are everywhere interpersed through the Albany River 

 section. Both the red and white pine appear to follow somewhat 

 closely the watershed in their northern limits of range. 



To the most casual observer the absence of trees and of mosses 

 is a striking feature of the prairies of Manitoba and westward. 

 That the frequent fires which devastate the prairies have much to 

 do with the scarcity of trees is beyond question. This very scarcity, 

 however, gives rise to a more than ordinary rapid evaporation of 

 moisture from the soil and thus deprives the mosses of that con- 



