Thinning Timber for Wildlife
Thinning produces numerous timber and wildlife benefits.
It improves the growth of the remaining trees and increases
the amount of sunlight reaching the forest floor, stimulating
the growth of a variety of herbs, forbs, legumes, and other
herbaceous plants used by wildlife. The increased sunlight
will also favor development of advanced regeneration of
oaks and other species which do not grow well in shaded
conditions. Thinnings increase the amount of available browse,
primarily from the sprout growth of cut trees. It also produces
temporary nesting cover from the tops of cut trees. It enables
harvested trees to be utilized before they die naturally
from competition. Finally, and of great importance to wildlife,
it increases potential mast production (acorns, hickory
nuts, etc.) as the crowns of the residual trees expand to
fill the space once occupied by the harvested trees.
Beneficial wildlife habitat practices to include when doing
a thinning are:
- Leave a variety of mast producers (oaks, hickory, gum,
beech, etc.) as crop trees in the residual stand. By doing
this, you decrease the possibility of having a complete
mast failure. If one species or group of species does not
produce mast in a particular year, there are other species
that may be successful.
- Encourage grapevines in a stand whenever possible. Grapevines
can be detrimental to quality timber production by breaking
the tops and limbs out of trees, but they provide excellent
food and cover for a variety of wildlife species. One grape
arbor (1/4-1/2 ac) per 3 to 5 acres is good. Vertical and
horizontal grape arbors offer two different types of cover.
Vertical arbors can be encouraged by leaving standing trees
with grapevines and felling adjacent trees into these trees
to create a tepee effect. Horizontal arbors can be created
by felling trees in a small area, where grapes are already
present, and letting the grapevines grow in the limbs and
branches on the ground.
- Leave wildlife cavity trees or den trees. Often times,
these poorer quality trees are ones you would consider removing
to allow better quality trees to grow; however, these trees
provide critical habitat for cavity nesting birds and mammals,
such as squirrels, raccoons, owls, woodpeckers, etc. Some
poorer quality trees that have the potential to develop
into cavity trees should be left if den trees are not prevalent.
Leave a minimum of 2 to 4 cavity trees per acre. In addition,
leave some dead snags in the stands for perch trees and
to provide possible feeding sites for insect foraging birds
and mammals.
- Leave an abundant supply of soft mast producers in the
stand, especially dogwoods, serviceberry, blackgum, hawthorn,
crabapple, etc., to provide an additional food source.
- Stabilize all haul roads, skid trails, and log landings
with a grass mixture which is beneficial to wildlife. This
will create additional habitat for grazing animals, such
as rabbits and deer, plus will serve as insect foraging
areas for songbirds, grouse, and turkey chicks. Fescue should
be avoided, except for the most steep areas, since it is
detrimental to wildlife.
- Protect spring seeps. They provide valuable feeding
areas for wildlife during winter when the countryside is
frozen or snowcovered. These areas are heavily utilized
by wildlife, especially turkeys. They should be buffered
by at least 100 feet from timber harvesting on each side
of the seep.
- Create waterholes where suitable sites exist by excavating
small depressions in areas that would tend to catch water
during rainy periods. Available water is a critical habitat
factor for wildlife, especially in late summer and early
fall. These are particularly important high up on the mountains
or on the upper slopes.
- Protect old homesites and abandoned orchards as they
provide unique habitats and usually contain a wide variety
of plant life, including fruit trees and shrubs, and are
heavily utilized by wildlife. Fruit trees should be released
and/or pruned to encourage increased fruit production.