58 College of Forestry 
is now heath-shrub and pitch pine. But in general, this val- 
ley rim up to 1000 feet elevation or rather more, is a sugar 
maple, beech, hemlock, pine region. (Zone C.) At Lake 
Bonaparte and Harrisville, (1400 feet) red spruce on up- 
lands, balsam and tamarack on flats and paper birch on pro- 
jecting points are indication of the Canadian-Transition 
(Zone D) which then becomes more intensified on through to 
the higher Adirondacks. Here it will be noted, sugar maple, 
beech, vellow birch, hemlock and white pine forest is rein- 
forced by the more boreal red spruce and balsam and paper 
birch and partly for this reason the zonal distinction,— Can- 
adian-Tr: ,—is made. But this distinction is streneth- 
ened by the character of the forest floor species. Thus, witch 
hobble, spimulose shield fern (Dryopteris spinulosa | Miuell. | 
Kuntze), and American shield fern (Dryopteris intermedia 
[Muhl] Gray) (especially the latter of these ferns), wood 
sorrel and shining club-moss (Lycopodiwn lucidulum 
Michx.) constitute the ereater per cent — some times practi- 
cally the whole — of a dense ground cover. Bunch berry, yel- 
low Clintonia and twin flower (Linnaea americana Forbes) 
yet more boreal species, are also abundant. The further re- 
sults of elevation are known to me chiefly by data from Mt. 
Marey and adjacent peaks. Between 3000 and 3500 feet one 
passes out of the Canadian-Transition Zone (D). 
The sugar-maple, beech, yellow birch, hemlock and 
white pine thin out, giving place to a (scarcely 
typical because rather dwarfed) Canadian Zone  for- 
est (EK), in which red spruce balsam, paper birch and 
mountain ash (Sorbus americana Marsh) are dominant. 
Above 4500 feet the forest becomes strongly dwarfed and a 
few hundred feet below the summit it is a dense serub thicket 
searcely man-high. This makes a compact mat-like growth 
still farther up in the ravines (See Fig. 3) and finally the 
conifers are mere dwarf, spreading shrubs. With this we 
come into a distinct zone (F) in which although species 
from lower elevations persist, the character giving species 
are arctic plants (see list under Zone F. indicators, page 77) 
