lodgepole competition.

In strictly lodgepole territory, however, it may be the only promise
of a new forest. Generally speaking, an even-aged growth should
be induced by clean cutting if the entire crop can be utilized.
Slash burning in such cases is desirable. The chief difficulty
is in providing seed supply, for either individual seed trees or
small groups are almost certain to be blown down. Experiments so
far indicate that heavy strips must be spared, chosen to afford
the least present loss and safeguarded by fire lines.

In some lodgepole stands, especially where only certain sizes are
marketable, the cutting practically amounts to thinning. Here obviously
the effort should be to prevent over-thinning and to remove debris
with the least damage to the remaining stand. Piling and burning
is essential.

SUGAR PINE (_P. Lambertiana_)

This extremely valuable pine, commercially limited to the Oregon and
California mountains, is fastidious in its choice of conditions. Not
a frequent or prolific seed bearer, it still insists on a moist loose
seed-bed and prefers the natural forest floor to burned-over land. It
cannot stand drought when young and except on cool northern slopes
seedlings may be killed or stunted by exposure to full sunlight. On
the contrary it demands more and more light as it grows older and
will be suppressed or killed if unable to secure it. Under natural
conditions it perpetuates itself best by filling open places in
the forest.