NATURAL HISTORY, TORONTO REGION 



broad-leaf component is represented by poplars, and 

 they often constitute one-fourth of the forest. 



As has been ' shown in the article (p. 51) by 

 Professor Coleman on the geology of the region, the 

 city of Toronto for the most part stands on light 

 sandy soils deposited in the Iroquois stage of Lake 

 Ontario, and the vegetation is characteristic of such 

 soils. The trees are mostly oaks and pines. There 

 are, however, patches of heavier soils, and where 

 their forest remains it is composed of beech and hem- 

 lock, notably in Ashbridge's woods in the eastern 

 part of the city. North of the old Iroquois beach 

 the soil gradually becomes heavier, with an increasing 

 clay content, and the oak-pine forest is replaced by 

 a maple-beech forest. 



On the western edge of the city, in High Park 

 and on the Humber plains, the vegetation is dis- 

 tinctly Carolinian in its relationships, while on the 

 eastern side it is Alleghanian, the city being the 

 dividing line between the two types of flora. The 

 transition between the two types is very abrupt in 

 High Park, where one may pass in a few minutes 

 from the Carolinian of the sand plains to the Alle- 

 ghanian in the bottom of the deep ravines. 



Toronto and vicinity offer excellent opportunities 

 for the study of vegetation in its various habitats; 

 in fact there are few places where one can find on so 

 small an area so many abrupt changes in the charac- 

 ter of vegetation due to variations in soil and in th( 

 micro-climatic conditions. One interested in 

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