TIMBER GROWING IK THE LODGEPOLE PINE REGION 7 
the exception of an extensive area in the vicinity of Butte and Ana- 
conda, Mont., where smelter fumes have killed all tree growth, is fire, 
either by itself or following cutting. 
Aside from the killing of timber by smelter fumes, most of the 
denudation took place prior to 1905. Fire protection in recent years 
has not only largely prevented any considerable increase but, through 
the encouragement of new growth, has actually brought about a 
reduction in the devastated area. However, restocking has been lim- 
ited to the immediate vicinity of islands of trees or individual trees 
of seed-bearing size which escaped fire. In such locations reproduc- 
tion of conifers has usually appeared, provided aspen or brush cover 
has not been too dense, or the growth of weeds and grass too heavy, 
or soil conditions and exposure too unfavorable — at best, a very slow 
process. Planting on a large scale with a good grade of nursery stock 
will still be necessary if these devastated lands are to be made pro- 
ductive within a reasonable time (S y 17) . x 
In general, the forests of the lodgepole pine region may be classi- 
fied in three major forest types : 2 Lodgepole pine, Engelmann spruce, 
and Douglas fir, the last-named including limited areas of the western 
yellow pine type. 
LODGEPOLE PINE TYPE 
The lodgepole pine type is the most important type in the whole 
region. It includes those tracts containing 50 per cent or more of 
lodgepole pine (Pinus contorta) , usually in pure, even-aged stands. 
Douglas fir (Pseudotsugw tamfolia) , Engelmann spruce (Piceaengel- 
mcmnii), limber pine (Pinus flexilis), and alpine fir (Abies lasio- 
carpa) often intermingle, but in relatively small proportions. Blue 
spruce (Picea pungens) and bristlecone pine (Pinus arista&a) are also 
found to some extent throughout the southern portion of the type. 
Large continuous stands of lodgepole pine, of fairly uniform volume, 
are an outstanding characteristic of the timbered portion of the 
region. 
This type ranges in elevation from about 6,000 feet in Montana 
and Idaho and 7,000 feet in Wyoming and Colorado, to a maximum 
elevation of about 9,500 feet. Its best development is reached in 
Wyoming at altitudes varying from about 7,500 to 9,000 feet. Exten- 
sive areas that will average from 12,000 to 15,000 board feet per acre 
and single acres containing as much as 25,000 board feet are to be 
found; but the average commercial stand of the region as a whole 
contains about 10,000 board feet per acre. This is, however, hardly 
expressive of the total volume involved, because of the large addi- 
tional volume contained in tops and trees too small to be measured 
in board feet. 
Dense, even-aged stands are characteristic of the type. (PI. 1, A.) 
In fact, in many instances they are seriously crowded and in a 
stagnant condition. (PI. 1, B.) This is brought about largely as 
a result of the persistence of the species in reestablishing itself after 
fire. However, the trees of these even-aged stands are not of uniform 
size, because the stronger individuals crowd and hold back the 
1 Italic figures in parentheses refer to publications listed in the bibliography, p. 33. 
2 Forest type is a term used to characterize forested areas throughout which a certain 
number of tree species occur in fairly consistent relationships. 
