28 The New York State College of forestry 
swamps— bunch berry, creeping snowberry, American twin 
flower and occasional cinnamon fern—thus showing ‘tlie 
pioneers of a later association which carries the sequence of 
development beyond the strictly bog series toward the balsam 
swamp forest type. 
(d) Transition Stage from Bog-Conifer to Balsam Swamp 
Forest. The oldest phase of vegetation now to be found on 
the Grasse River bog hes to the south of the railroad beginning 
near Silver Brook station. Specimens of standing dead tama- 
racks were found here measuring nearly 18 inches DBH and 
estimated to be approximately 100 feet tall. Apparently all 
of the old tamarack in this stand is dead. A gigantic specimen 
of black spruce in this vicinity, shown in fig. 20, measures 
over 20 inches DBH. ‘Some arbor vitae is found in this stand. 
Balsam is rather frequent and red maple oceurs sparingly. A 
single specimen of red spruce was noted. To one who has 
become accustomed to the monotony of a black spruce tama- 
rack association, these added species are striking signs of a 
changed status of affairs in the bog. Inquiring into the nature 
of this changed status, one finds that while the peat bed is 
here some 3 feet deep, it is obviously more decomposed, beimg 
blacker and more mucklike. The surface of the bog—the 
forest floor — is broken up by the massive roots of trees, elevated 
about their buttressed bases and upon uprooted specimens 
(fig. 21) or on rotting stumps. A heavier forest litter covers 
the ground. Thus, while it is a wet habitat, the upbuilt sur- 
face at least is fairly well drained and aerated during much 
of the growing season. Sphagnum is still abundant, but is 
often suppressed by incoming: species, notably cinnamon fern. 
Fig. 20. Patches of Oxalis acetosella wpon the uplifted sphag- 
num covered forest floor give the appearance often seen in 
stands of red spruce. Fig. 21. The list of non-bog species 
is now fairly large. It ineludes the bunchberry, American 
twin flower and creeping snowberry mentioned in the preeed- 
ing phase (c). Beside these and the oxalis and fern just 
mentioned there are Dalibarda repens, Coptis trifolia, Unifo- 
lium canadense, Gaultheria procumbens, Aspidium  inter- 
