30 The New York State College of Forestry 
sphagnum-shrub mounds: the succession of tall shrubs in the 
well established sphagnum-dwarf shrub association; the early 
stages of black spruce-tamarack invasion of the older shrub 
type; the closed conifer association before pruning; the true 
forest stand of black spruce and tamarack and finally the more 
complex association of these species with balsam, red maple 
and a larger series of forest floor associates. These have been 
presented with the purpose of showing that peat bed vegeta- 
tion is of a specialized kind involving the elimination of many 
species otherwise occurring in wet situations and the selection 
of a restricted list of bog tolerant species —— phenomena, of 
course, already well known among botanists; second, that the 
several types and their intergradations represent a sequence of 
vegetation development — the so-called bog sequence.* The 
term sequence or succession 1s meant to ee that all these 
associations are developmentally related, i. e., that each phase 
of vegetation or association causes changes it the substratum 
which literally prepare the ground for species of different soil 
requirements. It appears that in the oldest and apparently 
most stable association —the early balsam-swamp type— the 
substratum is approaching a condition where the percentage 
of balsam may be expected to increase and it is conceivable 
that the further upbuilding and differentiation of the still wet 
substratum with the consequent appearance of greater numbers 
of less hydrophytice forest floor species, may be creating con- 
ditions which will more and more favor the entrance of yellow 
birch (numerous seedlings of which are found on decayed and 
half buried logs), of white pine and gradually of hemlock, 
beech and hard maple—that is the regional climax associa- 
tion with its characteristic well drained and aerated crumbly 
leaf mold soil and equaily characteristic forest floor species. 
The writer has not, it must be repeated, observed any case In 
the Adirondacks where such a regional climax forest has devel- 
oped upon a peat bed, so it appears that the balsam swamp 
type of forest is the persistent if temporary edaphic climax 
of a bog sequence. This does not bear the inference, however, 
that in the Adirondacks balsam swamp forests are generally 
* See, for example, Dachnowsky (7), 237. 
