Forest Development in the Advrondacks OL 
found to be underlaid by sphagnum peat. Indeed, the Grasse 
River sand plain itself gives indications that this type may 
develop on low, rather wet sand beds. See pages 32, 33. 
It must not be understood that this presentation of the 
vegetation sequence of the peat beds of the Grasse River plain 
assumes the tracing of an uninterrupted original succession, 
As has been stated, recent fires in the sphagnum-sedge and in 
the open dwarf shrub zones havé materially affected the course 
of vegetation. In the east section of the bog in the sedge zone 
to a less extent, but notably in the pure shrub zone, there are 
still to be found standing, fire charred snags and numerous 
buried logs and stumps also party burned which indicate a 
former black spruce-tamarack forest over the whole of this 
area. Fig. 14 shows a standing burned snag and fig. 13 a 
burned stump of trees that must have been over 50 years old 
and represent remnants of a growth that had established forest 
conditions including clear boles, a canopy and heavily shaded 
forest floor. No doubt the local history would reveal notable 
changes in the vegetation of the bog within the memory of the 
long time residents of the vicinity. 
VEGETATION OF THE NON-PEAT COVERED SAND PLAIN 
The locally descriptive name Grasse River Marsh refers 
especially to the low lying peat covered lands—the bog as 
just described. The sand plain considered as a whole presents 
also low elevations from flat scarcely discernible rises barely 
above bog level to well defined undulations or low ridges. The 
esker like ridge separating the bog from the flood plain has 
been pointed out already as an important feature. Finally 
one-half of the west section of the plain —notably between 
Burnt Rock and the mouth of Silver Brook— les above the 
peat forming level, though it is still to be classed as low land. 
No attempt is made here to analyze the vegetation cover of 
these sand beds minutely or to establish except in a genera! 
way its successional aspects. It is particularly cited in con- 
trast with the situation just described, where the bog sequence 
of vegetation is determined. Figs. 4, 5, 22 show what appear 
