Vegetation of Northern Cape Breton. 293 



border of the transition region, as in Cape Breton, purely 

 deciduous forests are by no means lacking, and that the trees of 

 group A growing here compare quite favorably in size, vigor 

 and ability to reproduce themselves with those growing in 

 forests farther south. It is of further interest that along the 

 southern border of the transition region the trees of group D 

 may occupy a prominent position in climax forests : in one 

 locality in northwestern Connecticut, for example, at an eleva- 

 tion of less than 2,000 feet, the black spruce is thriving on 

 uplands, reproducing well, attaining a large size, and growing 

 in association, not only with beech and maple, birch and hemlock, 

 but wath such species as chestnut (Castanea dcntata) and 

 mountain laurel. 



Considerable interest attaches itself to the relative importance, 

 in transition forests where the trees of group D are represented, 

 of the balsam fir and black spruce. In northern Michigan 

 (Whitford '01), Ontario (Howe & White '13), and elsewhere 

 the balsam fir, as in Cape Breton, seems to be the predominant 

 northern conifer. But in other localities the black spruce 

 occupies the position of relative predominance. This seems to 

 be true, to cite localities with which the author is personally 

 familiar, in the western Adirondacks and in northwestern 

 Maine. In the primeval forests about Big Moose (elevation 

 about 2,000 feet), in the Adirondacks, for example, where it 

 grows abundantly, in company with beech, sugar maple, yellow 

 birch, and hemlock, the black spruce attains a diameter of more 

 than three, and a height of more than 125 feet. Here, as in 

 Maine, the balsam fir is present in the forest, but it is more 

 characteristic of the "flats" and moister sites. As noted earlier, 

 the black spruce is represented in the climax forests of the low- 

 land in northern Cape Breton, but here it is infrequent and 

 never reaches the size exhibited by the spruce in the Adirondacks. 



In proceeding northward from the region of deciduous 

 forests to that of coniferous forests (Fig. i) there is a gradual 

 transition from one type of forest to the other. Broadly speak- 

 ing, however, due largely to the predominating influence of the 

 deciduous element, forests of the regional climax type are 

 essentially similar in their ecological aspect throughout the 

 transition region. Various attempts have been made to define 

 subdivisions of this region on the basis of vegetational dissimi- 



