Op Se er Pe Se pe ee en mee ee atk. 
eS ok a ao A ee eee ee Oe Se 
OT ee ee as aie ees 
1913] COOPER—ISLE ROYALE 39 
higher grounds, where it ams has the balsam and birch as its 
companions. 
The data here presented, though very unsatisfactory, are 
sufficient in my opinion to establish the probability of the generali- 
zation that the climax type of the whole of the northeastern conifer 
region is of the general character described for Isle Royale, with 
local variations due to the elimination or addition of species, or to 
the substitution of others that are ecological equivalents. 
Important confirmation has recently been received from Dr. 
ROBERT BELL of Ottawa, the best authority upon the distribution 
of Canadian trees, who writes: ‘‘The same type of upland forest 
which you describe on Isle Royale extends from the Great Lakes 
to James Bay and east and west of it, with modifications in parts.” 
On the map (fig. 14) the area shaded with oblique lines repre- 
sents the region over which the ranges of the balsam, paper birch, 
and white spruce overlap, north of the range of the sugar maple 
(data largely from TRANSEAU 55). It is in this region that the 
type of forest described is thought to be the climax. Beyond the 
limits of the balsam, which has the narrowest range of the three, 
some other species must be substituted for it, or else the climax 
_ forest is composed of the remaining two species alone. 
COMPARISON WITH THE CONIFER FOREST OF THE SOUTHERN APPA- 
LACHIAN SUMMITS 
In connection with the study of the Isle Royale forest it will 
be worth while to make comparison with another region that has 
come under my observation, where the forest is extremely similar 
to that described in the present paper. On the highest summits 
of the mountains of North Carolina, eastern Tennessee, and south- 
western Virginia, there are isolated areas of dominantly coniferous 
forest, which seem like detached portions of the great northeastern 
forest (see detailed description by HARSHBERGER 32). The 
species are different, the balsam being Abies Fraseri (Pursh) Poir., 
_ the spruce Picea rubra (DuRoi) Dietr., and the birch Betula lutea 
Michx. f. In general aspect this forest’is surprisingly like that of 
Isle Royale. Because of the predominance of the first tree men- 
tioned many of the mountains themselves are locally called “Bal- 
