4 
BULLETIN 55, U. S. DEPARTMENT OF AGBICTTLTUKE. 
Southward balsam fir is found almost all over Canada, particularly 
in its maritime provinces — Quebec and Ontario — in northern New 
England, and in the northern parts of New York, Michigan, Wisconsin, 
Minnesota, and northeastern Iowa. Along the Appalachian Moun- 
tains it extends through western Massachusetts, over the Catskills of 
New York, and through western Pennsylvania to the mountains of 
southwestern Virginia. 
The heaviest commercial stands of balsam fir are found in Canada, 
in Quebec and Ontario. On the Cape Breton Islands, according to 
Dr. Fernow. 1 balsam fir forms a solid forest, with not over 15 per cent 
of spruce and a small admixture of paper birch, covering a plateau of 
1,000 square miles. It is estimated to compose more than 50 per cent 
of the forest, 150,000 square miles in extent, on the southern slope of 
the Laurentian shield, south of the height of land. In the United 
States balsam fir is found in commercial quantities in most of Maine, 
the northern parts of New Hampshire, Vermont, New York, and to 
some extent also in the swamps of northern Wisconsin, northern 
Michigan, and Minnesota, or, in all, over an area of approximately 
35,000 square miles. 
FOREST TYPES. 
The same factors that control the geographical distribution of 
balsam fir influence to a great extent also its local occurrence. Maine, 
with an average summer temperature of only 62.5° F., an average 
winter temperature of 20° ¥. 3 and a mean annual rainfall of 43 inches, 
presents most favorable conditions for the tree's growth, and, indeed, 
here balsam fir is in general more thrifty than in any other State in 
which it occurs. This is shown in every way — in the greater height, 
larger diameter, greater clear length, more cylindrical shape of the 
trunk, and the smoother appearance of the bark, indicating a more 
rapid growth. 
The forest types in which balsam fir occurs in Maine, as well as 
throughout northern New York, New Hampshire, and Vermont, 
may be classified as swamp, flat, hardwood slope, and mountain top. 
SWAMP. 
The swamp type occupies low, poorly drained, swampy land which 
never becomes entirely dry, and on which sphagnum and other 
mosses form the predominating ground cover. In such swamps 
balsam fir grows in dense stands and remains exceedingly slender, but is 
remarkably free from injury by fungus, especially from ground rot and 
from wind and frost cracks. It often grows nearly pure, though com- 
monly it is mixed with black and red spruce, white cedar, and tamarack. 
On account of its small size and slow growth, the balsam fir of the 
swamps is of little commercial value. This slow growth may be attrib- 
i Forest Problems and Forest Resources of Canada, by Dr. B. E. Fernow, University of Toronto. 
Proceedings of the Society of American Foresters, Vol. VII, No. 2, 1912. 
