On many national forest areas the control of porcupines is imperative
from the standpoint of timber reproduction. This is especially true on
cut-over areas and where fires have destroyed all seedlings. Porcupines
will often destroy up to 90 percent of the seedlings and, through
continued girdling of young trees 15 to 25 years of age, will destroy
all chance for commercial timber for many years to come.
[Illustration: Typical porcupine den. Picture taken on Pike National
Forest in Colorado, in area where porcupine control work was conducted
under the Forest Service E.C.W. program.]
[Illustration: Porcupine at work girdling pine tree.]
[Illustration: Showing one of 114 young pines damaged by porcupines on
15 acres.]
[Illustration: Additional evidence on cut-over areas.]
[Illustration: Porcupine at foot of tree probably 15 years old, which
it has damaged beyond hope of recovery.]
[Illustration: Complete girdling by porcupines about 12 inches above
ground.]