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Upland
Hardwood Management
Upland hardwoods
are a very important habitat type for much of our wildlife in
Virginia. On any property where wildlife habitat is a goal some
hardwoods should be retained. Some may need to be harvested and
others may need some work to keep the stand growing well and to
improve their quality for wildlife.
Regeneration
of upland hardwood stands that are dominated by oaks is a
process that is not easily controlled by management. Basically
on your poorer sites oaks will come back almost regardless of
what you do. These are the sites that foresters generally
recommend for conversion to pine due to the long rotation age
and poor quality of the native hardwoods. On your extremely good
sites it is probably safe to say no one has come up with a way
to bring oaks back. On the intermediate quality sites it may be
possible to bring oaks back with a shelterwood cut. This cut
involves reducing the overstory down to a level of about 45 sqft/ac
basal area, then several years later removing the remainder of
the trees in a final harvest. The number of years between the
two cuts is determined by how long it takes to get an adequate
number of vigorous oak seedlings established. A period of from
five to fifteen years will suffice depending on the timing and
size of mast crops. One significant benefit of a shelterwood is
that during the period between cuts the site provides high
quality wildlife habitat. It should be kept in mind that the
production of oaks on these intermediate quality sites may not
give a strong financial return. If current trends in hardwood
prices continue however, these sites may be profitable for
growing hardwoods. In any case it is impossible to guess at
timber prices 40 to 80 years into the future. Besides using a
shelterwood cut, a very clean clearcut can be used to regenerate
oaks on these medium quality sites with a reasonably good
prospect of success.
On small
tracts of land it is certainly desirable to release crop trees
when they have reached about 25 feet in height. At this point
they have already demonstrated their dominance and vigor and it
will be relatively easy to select preferred trees. Competing
trees with adjacent crowns should be removed by either cutting
or herbiciding. It should be kept in mind that this is a labor
intensive task that will not pay for itself economically until
the timber reaches maturity, at which time the improvement in
the stand quality will be significant.
Thinnings are
as important in hardwoods as they are in pines. Unfortunately,
it is usually difficult to get them done. Whenever possible you
should try to thin these stands as soon as it is commercially
possible - 40-50 years old. It may be possible to thin a second
time in approximately 10 to 15 years. Residual densities in
hardwoods should be fairly similar to those for pines at about
55 sqft/ac (50-65) on the first thinning, and perhaps five to
ten square feet higher on successive cuts. In thinning hardwood
stands it is important for wildlife benefits to maintain a high
degree of species diversity. Keeping about 50-60% of the trees
in oaks, evenly divided between red and white oak groups is a
good goal. Although the timber value is less it is important to
retain hickories, beeches, black gums and maples. These trees
all provide valuable food to a wide variety of wildlife species.
Also large hollow trees should be kept wherever possible because
of their value as den sites. With the almost certain arrival of
gypsy moths in the area in the next several years it is
important to maintain both vigor and diversity in upland oak
stands.
Prescribed
burning should be precluded from hardwood stands unless they are
very young (< 5-10 years) or very old (>65 years). In seedling
stage hardwoods fire can be very helpful in encouraging oaks and
hickories. As the trees get into the sapling and pole stages
fire will cause serious damage due to the thin bark. Fire should
always be precluded from high site quality hardwoods regardless
of age.
Bottomland
Hardwood Management
Bottomland
hardwoods, swamps to some, provide excellent quality wildlife
habitat. In most cases, without a great deal of work, they
provide very few opportunities for forest management. With this
in mind the best advise for most of these areas is to leave them
alone. In some cases it can be useful to selectively release
oaks and beeches where they are competing with the more common
maples, birches, gums and sycamores. This is not a commercial
operation and would best be done for firewood or even leaving
the felled trees in the woods. Where the drainage pattern
permits it may be possible to create a green-tree reservoir. To
be effective such an area should be dominated by oaks. These
sites are fairly rare in the Piedmont.
Timber
Sales
Selling
timber should always be done with a signed contract in order to
protect your interests and to help insure the best possible
work. Layout of any sale should leave buffer strips along
wetland areas such as permanently flowing streams, ponds, lakes,
and beaver swamps. These buffer strips should be wide enough to
provide good quality wildlife movement corridors and habitat
diversity: about 100-150 feet wide on each side of the water
body. When large tracts are harvested, this type of habitat can
be extremely valuable to all types of wildlife.
Intermittent
streams should have smaller buffers left to provide additional
habitat for wildlife. These buffers need only be about 50-75
feet in total width. Forestry Best Management Practices (BMPs)
call for only 50 foot wide buffers, which provide only minimal
benefits for wildlife. Leaving out buffers of mature timber as
described here may result in a 5 to 10% loss of acreage in the
sale. This may reduce the sale price per acre, but keep in mind
the timber in the buffers will continue to grow (and in many
cases become more valuable) and be available for future sales.
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