Vegetation of Northern Cape Breton. 301 



tially similar to what has been described above as constituting 

 the ultimate phase in the rock outcrop series : a forest of 

 balsam fir, white spruce, paper birch, etc. And it is of interest 

 to note that, locally, such a forest may also constitute an edaphic 

 climax, even on the drift. In the vicinity of Baddeck, for 

 example, over most of the country succession has never pro- 

 gressed beyond the coniferous forest stage. This circumstance, 

 without much question, is correlated with the heavy, clayey 

 nature of the drift here, which has acted as a limiting factor to 

 prevent the attainment of the regional climax. It is of further 

 interest in this connection that around Baddeck, and in certain 

 other localities where the soil is heavy, the tamarack {Larix 

 laricina) is an important arborescent pioneer and a constituent 

 of the coniferous forest. Throughout much of northern Cape 

 Breton the tamarack is a rarity. Its ecological status will be 

 referred to again in another connection (p. 412). 



Development of the regional climax. — The yellow birch may 

 be regarded as the forerunner of the deciduous trees which 

 characterize the regional climax forests. This tree is usually 

 represented in coniferous forests in the lowland, but there it 

 occupies a position of prominence only in forests which are well 

 advanced in their development. As the pioneer among the 

 deciduous climax trees, it seems not unlikely that this tree, 

 together with the red maple and paper birch, may help to pave 

 the way for the beech and sugar maple. The efifect on the moss 

 carpet of the periodic accumulation of fallen leaves has been 

 referred to elsewhere ; and it is at least conceivable that the 

 deciduous advance-guard in the coniferous forest, through the 

 medium of leaf-fall, may in some way exert an ameliorating 

 influence on the substratum, which facilitates the invasion of the 

 forest by beech and sugar maple. 



At any rate, wherever the soil conditions are favorable, conif- 

 erous forests are superseded by forests of the regional climax 

 type. The trees of the coniferous forest stage in the succession 

 may persist in varying degree, as earlier suggested, but they 

 relinquish their position of dominance. All stages of transition 

 may be found between forests of the coniferous type and those 

 which are purely deciduous. During the transition from one 

 type to another the undergrowth undergoes various changes. 

 Certain species of the coniferous forest stage, such as Coptis 



