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orests
are an important part of our state’s environment and economy. When they
are well managed, forests provide clean air and water, homes for wildlife,
beautiful scenery, places for recreation and more than 5,000 products we
all use every day. But when they are not well managed, forests are often
unhealthy and unproductive because of overcrowding, disease, insects, and
competition for light, water and nutrients. To maintain or improve the
health and productivity of a forest and to achieve the landowner’s
objectives for the property, foresters use a number of management
techniques, including prescribed burning, thinning, harvesting and
planting.
In forest management, trees
are harvested for a variety of reasons including improving the health of the
forest; controlling the types of trees that grow on the site; attracting
certain wildlife species; providing a source of income for the landowner;
producing paper, lumber and numerous other forest products; and improving
access to the area for hikers, hunters and other recreational users.
ust as there are many
reasons for harvesting trees, there are many different harvesting methods.
Each method has its benefits, drawbacks and conditions under which it is the
most suitable way to harvest trees. No one harvesting method is ideal for all
situations.
Clearcut
Clearcutting
removes all the trees in a given area, much like a wildfire, hurricane or
other natural disturbance would do. It is used most frequently in pine
forests, which require full sunlight to grow, and in hardwood forests with
yellow poplar, sweetgum, cherry, maple and other species that require full
sunlight.
Clearcuts are an efficient way to convert unhealthy stands to healthy,
productive forests because they allow forest managers to control the tree
species that grow on the site through natural or artificial regeneration.
While a clearcut removes all canopy cover and is unattractive for a short
period of time, it is an effective method for creating habitat for a variety
of wildlife species. Animals that eat insects, such as turkeys and quails, and
those that eat annual and perennial plants, such as bears and deer, thrive in
recently clearcut areas. Many creatures also find shelter from weather and
predators in the low growing grasses, bushes and briar thickets that follow
this type of harvest. In addition, clearcutting is an important forest
management tool because it can be used to create edges - areas where two
habitat types or two ages of the same habitat meet. Because edges provide easy
access to more than one habitat, they usually have more diverse wildlife
communities than large blocks of a single habitat.
Shelterwood
In
a shelterwood cut, mature trees are removed in two or three harvests over a
period of 10 to 15 years. This method allows regeneration of medium to low
shade-tolerant species because a "shelter" is left to protect them.
Many hardwoods, such as oak, hickory and cherry, can produce and maintain
seedlings or sprouts in light shade under a partially cut stand. However, the
young trees will not grow and develop fully until the remaining overstory
trees are removed.
One benefit to shelterwood harvests is that they provide cover and early
successional food sources for wildlife. However, this method of harvest is not
recommended for trees with shallow root systems because the remaining trees
are more susceptible to wind damage after neighboring trees are removed.
Another disadvantage to shelterwood cuts is that they require more roads to be
built through the forest, and increase the risk of soil disturbance and damage
to the remaining trees during harvesting.
Seed Tree
In
a seed tree harvest, five or more scattered trees per acre are left in the
harvested area to provide seeds for a new forest stand. These trees are
selected based on their growth rate, form, seeding ability, wind resistance
and future marketability.
Wildlife benefit from seed tree harvests in much the same way as they do
from a clearcut harvest, except that they also reap the benefits of the seed
trees themselves. If left on site indefinitely, seed trees eventually may
become snags or downed logs, which are important habitat components for
woodpeckers and many other species. Seed trees are also excellent food sources
and nesting sites for hawks and other birds.
One disadvantage to seed tree harvests is that the remaining trees are at
increased risk of damage from wind, lightening, insect attack and logging of
nearby trees. This type harvest may also require the landowner to make future
investments in thinning and competition control because of uncontrolled
reseeding.
Group Selection
Group
selection is essentially a small-scale clearcut where groups of trees in a
given area are harvested over many years so that the entire stand has been cut
within 40 to 50 years. This method is used primarily on bottomland hardwood
stands to harvest high-quality, top dollar logs. The size of the group cut
determines the tree species that are likely to return after the harvest.
Openings that are less than one-fourth acre favor shade-tolerant species, and
larger openings favor sun-loving species.
Group selection provides ideal pockets of young vegetation for grouse,
deer and songbirds. But because it requires intensive management and frequent
access to all areas of the property, it can be an expensive forest
regeneration method.
Single-Tree
Selection
Single-tree
selection, the most intensive harvesting method, removes individual trees that
are ready for harvest, of low value or in competition with other trees. With
single-tree selection, the forest continuously produces timber and constantly
has new seedlings emerging to take the place of harvested trees. Single-tree
selection maintains a late succession forest that benefits many wildlife
species such as squirrels and turkey.
Single-tree selection harvesting is best in small or confined areas for a
variety of reasons. One is that this harvesting method requires more roads. In
addition, surrounding trees can be damaged during harvests, and frequent use
of logging equipment in a given area may compact the soil. Sun-loving trees,
which are an important source of food for wildlife, do not regenerate well
with single-tree selection, so forest managers must use mechanical or chemical
controls to prevent shade-tolerant species from taking over the site.

When trees are crowded together, they
are in greater competition for sunlight, nutrients and water. As a result, they tend to be
less healthy and to grow less vigorously. To improve the health and productivity of the
forest, forest managers may thin the forest or remove a portion of the trees -- usually
low quality trees that are competing with healthier trees for sunlight, water and
nutrients. Thinning allows the remaining trees to grow faster and stronger and improves
the growth of the forests understory by increasing the amount of sunlight that
reaches the forest floor. This understory growth provides more food and cover for animals
such as deer, quail and rabbits.

The wonderful thing about
trees is that they are a renewable resource. This means that they can be
grown, harvested, replanted and harvested again and again in a never-ending
cycle to provide clean air and water, habitat for wildlife, beautiful views
and thousands of products both today and in the future.
The process of growing trees
on an area that previously has been harvested or cleared is called
reforestation. The two basic methods of reforestation are natural regeneration
and artificial regeneration.Natural regeneration relies
on nature to return an area to forestland after trees are harvested. Through
natural regeneration, new trees grow from seeds that are carried by the wind,
transported or buried by animals, or that are simply dropped on site by mature
trees. In addition to producing seedlings from seeds, hardwood trees
regenerate naturally by sprouting new growth from the stumps of cut trees.
Artificial regeneration
involves human intervention in sowing seeds or planting seedlings. This method
of forest renewal has several advantages over natural regeneration. It
provides better control over tree spacing, more control over the species
present in the new forest, the opportunity to plant genetically improved seeds
or seedlings, and a higher rate of tree survival. Although artificial
regeneration is more expensive than natural regeneration, the result is
usually a more productive stand in a shorter period of time.

Most people are aware that devastating
wildfires destroy thousands of acres of forestland every year, but they dont realize
that controlled or prescribed fire can actually be good for a forest.
Prescribed burning is a forest
management practice that benefits certain forests by reducing the amount of leaves,
branches and dead trees accumulated on the forest floor that could fuel a wildfire. In
addition to helping control the spread of wildfire, removal of this "litter
layer" also promotes the growth of new forage and succulent plants, which are
important sources of food for many wildlife species including rabbits and deer. And the
increase in available insects and seeds following a prescribed fire is good for turkeys
and a variety of nongame species.
While improving wildlife habitat,
prescribed fire also promotes the health of the forest by controlling the spread of
disease and insect infestations, and reducing plant competition for nutrients, water and
sunlight. This management technique is commonly used in longleaf, shortleaf and loblolly
pine forests because these trees are naturally resistant to fire. In fact, the longleaf
pine requires fire for its seeds to germinate.

Each stage of succession provides different benefits to a variety of wildlife
species. In fact, many species need more than one forest type to meet their
needs. Rodents and rabbits prefer early successional forest where there are plenty
of grasses and shrubs for food and shelter. Deer also need food found in early
succession, but require the denser cover of middle and late succession for shelter and
escape from danger. Birds of prey nest in mature forests, but feed on rodents and
snakes found in early succession. Other wildlife, such as squirrels, find both their
food and shelter in mature trees.
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