Forests of Canada. 6Y 



Canada is perhaps as great as that in the United States. 

 It is, therefore, evident that the forests are less diversified 

 in the north than in the south. This is in accordance with 

 the general law of the greater richness of the flora of warm 

 countries ; but it may be clue also in part to the fact that in 

 the north we have greater uniformity of physical and 

 climatic conditions over wide areas than in the south. For 

 example, we have a similarity in these conditions from New- 

 foundland to Alaska, and hence throughout the great dis- 

 tance of 4,000 miles we find the same group of trees. Again 

 in the great triangular area of the Northwest, between the 

 United States boundary, the Eocky Mountains, and the Lau- 

 rentian region, embracing over 600,000 square miles, very 

 little difference could be observed in the climate, the soil, or 

 the general level of the country, and hence the same group 

 of trees — only about half a dozen in all — is found through- 

 out this immense tract. In striking contrast with this is 

 the fact that on the same farm lot in the south-western part 

 of the Province of Ontario one may often count as many as 

 fifty different kinds of trees. The richness in variety of the 

 native trees of Ontario and the adjacent States is owing to 

 the fertile soil and the favourable conditions as to summer 

 temperature, constant moisture, and the absence of intense 

 cold in the winter. 



The writer exhibited a map showing the northern and 

 western limits of the principal forest trees of the Dominion 

 east of the Eocky Mountains. From this it appears that 

 the range of species is not according to the mean annual 

 temperature or precipitation, but rather to the absence 

 of extremes of heat and cold, and of great dryness. For 

 these reasons a number of the trees of the Province of 

 Quebec and northern Ontario do not range west into Mani- 

 toba, although the annual means of temperature and preci- 

 pitation are nearly the same in both. This map also shows 

 in a striking manner that the northern limits of our various 

 forest trees are by no means parallel to one another, 

 although locally some groups may be nearly so for a certain 

 distance. Some of them pursue extraordinary or eccentric 

 courses, which are difficult to account for. The most 



