SILVICULTURAL CHARACTERISTICS 31 



dead firs under heavy shade are much more common than dead 

 spruce. It will live under shade the first few years, but requires 

 more light as it develops. For good development the balsam 

 requires a richer and moister soil than spruce. It reaches its 

 largest size on flats where the soil is a moderately moist, deep 

 loam. In wet swamps with acid soils and on pure sand it grows 

 very slowly. 



The balsam is particularly apt to be attacked by fungi which 

 cause its decay and death at an early age. Because of rot this 

 tree is much more apt to be broken off by wind than to be up- 

 rooted, as is the spruce. It is also especially susceptible to injury 

 by fire, since the cambium is but slightly protected by thin 

 bark. 



The balsam is a fairly rapid growing tree, though not as much 

 so as the white pine. During the first five years its height 

 growth is much slower than that of pine or Norway spruce, but 

 from that point onwards until sixty years old, it averages, under 

 favorable conditions, nearly a foot a year. Crowded in a forest 

 its growth is somewhat less. The most rapid diameter growth 

 is between the ages of twenty and seventy years, during which 

 time it requires an average of nine years for one inch of growth 

 on the radius. 



Balsam fir is used both for pulp and lumber. Because of its 

 pitch content it is inferior for pulp purposes to spruce. Most 

 pulp mills in the northeast now use balsam up to 40 per cent 

 mixed with spruce. For lumber purposes it is customary to sell 

 balsam with spruce and there is usually no difference in price, 

 except for first grade. 



HEMLOCK (Tsuga canadensis) . 



The range of hemlock is from Newfoundland west to Minne- 

 sota and south to Georgia. It is common throughout New 

 England and New York. 



The hemlock is only a little more particular than the pine in 

 regard to soil as it will grow in dry situations, though like many 



