462 George E. Nichols, Vegetation of Northern Cape Breton. 



highland are represented in siiccessional series, in favorable 

 situations being destined to give way to forests of the deciduous 

 type but in many unfavorable situations constituting edaphic 

 climaxes. 



In the highland the same general relations hold true as in the 

 lowland between associations of the regional climax type and 

 those which are more primitive. But here, owing mainly to the 

 humidity of the climate, the influence of dissimilar edaphic condi- 

 tions is less pronounced than in the lowland. It can be stated 

 in general that the influence of soil and topography on the 

 character and distribution of plant associations is least pro- 

 nounced in humid climates, most pronounced in arid climates : 

 that this influence is universally proportional to the dryness of 

 the climate. 



The barrens represent an edaphic association-complex, the 

 character of the vegetation being correlated with conditions of 

 exposure, topography and soil. Of especial interest here is the 

 extensive development of heath and of various types of scrubby 

 forest and of raised bogs. Particular attention is called to the 

 important part played in the development of the latter by different 

 species of Sphagnum. 



