LIFE HISTORY OF LODGEPOLE PINE IN ROCKY MOUNTAINS. 13 
should be reduced to about 500 at the end of 30 years, to about 300 
at the end of 90 years, and to about 250 by the one hundred and 
fortieth year, when the stand may be considered mature. Unfortu- 
nately, owing to the low mortality rate of lodgepole pine, a stand of 
1,000 evenly distributed seedlings 10 years old will not, by natural 
means, be reduced to 500 at 30 years, 300 at 90 years, and 250 at 
140 years. Ordinarily this could be brought about only by thinning. 
Tf, however, the stand is sufficiently open to arrive at maturity with 
250 stems per acre without thinning, decidedly limby trees will be 
the result. On the other hand, a stand of 1,000 well-spaced seed- 
lings 10 years old, at which age a stand may be considered as 
established, probably will have about half that number of trees 
at maturity. In such a case those of fairly good form and diameter 
may be cut and the others left to grow for an additional period. 
Seedling stands of from 300 to 500 plants per acre are preferable 
to those of 8,000 or more, even when thinning is possible, since for 
many years the latter will not produce material which can be taken 
out with profit in the course of thinning. Thinnings, moreover, 
will probably be impracticable, except in a few localities, and for 
this reason from 300 to 500 seedlings may generally be considered 
preferable to 2,000 or more. A good volume of limby timber is 
better than a large number of poles; besides, the spaces in an open 
stand will gradually fill in with individuals of a more satisfactory 
form. Where thinnings are practicable a density of about 2,000 
plants at the start is best. Plate ITT, figure 2, shows a well-developed 
- 60-year-old stand of lodgepole of something less than normal density. 
It should be borne in mind that the figures for density given in 
the preceding paragraph are more or less arbitrary, and in deter- 
mining the normality of a stand as much attention should be given 
to the spacing and height growth as to the-number of stems. A 
relatively large number of trees per acre is not undesirable, provided 
there is enough variation in the height of individual trees to pre- 
vent stagnation of growth. 
The production of clean stems is of comparatively little im- 
portance, since lodgepole is used mainly for mine timbers and rail- 
way ties, and in the future is not likely to have additional uses other 
than for telephone poles, pulp, and common lumber. Of far greater 
importance than clean stems are rapid growth and the production 
of large-sized timber. Lodgepole is slow-growing, and there is 
always an abundance of trees of small size. Ordinarily there is 
far greater danger of overstocking than of understocking. Ob- 
servations on 40,585 acres of young growth on the Deerlodge 
National Forest show 78.7 per cent of the entire area to be over- 
stocked, 20.5 per cent understocked, and only 0.8 per cent normally 
stocked. 
