FOREST TREES 
species of great economic importance. 
Lastly, in their habit of denser growth, 
and from the fact that these trees are 
ordinarily found in the form of “ pure” 
forests (in contradistinction to those 
forests in which a number of species 
grow intermingled), they furnish cer- 
tain very important conditions for prac- 
tical and successful forestry. 
The common white pine well de- 
serves to stand at the head of all the 
conifers or evergreens east of the Mis- 
sissippi. Though it once covered vast 
areas in more or less “pure” forests 
it has been largely cut away, and re- 
curring fires have generally prevented 
its return; but in certain places it could 
even now be restored by careful treat- 
ment. At present the last remnants of 
; these pineries are disappearing swiftly, 
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