IIT 
DISTRIBUTION OF AMERICAN 
FORESTS 
HE geographical distribution of 
trees has been referred to occa- 
sionally in the preceding chapters. 
This distribution, gradually accom- 
plished during the progress of ages, 
has not been accidental; on the con- 
trary, it has been due to natural causes, 
and arises out of the special needs and 
adaptations of each species. The geol- 
ogy of a region, which determines in 
many respects the character of the phy- 
sical forces of both the earth and the air, 
is no small factor in the development 
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