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Starting Point Diagnosis
= The Site is Mixed with Pines and Hardwoods
Many historical longleaf pine sites have become occupied today by forests
composed of loblolly and/or shortleaf pine and mixed hardwoods. In much
of the natural longleaf range, this is the typical forest condition following
a total harvest if no attempt is made to reforest. These forests can produce
valuable timber, excellent wildlife habitat, and are often aesthetically
pleasing. Still, they occupy sites that once supported longleaf pine ecosystems
and are well suited to that forest type. In order to restore that ecosystem
to these sites, planting longleaf seedlings will be necessary. One technique
that has been applied successfully begins with the commercial harvest
of the hardwood component, followed by a growing season fire, preferably
in late March through mid-May. Clearing logging slash away from the boles
of the residual pines manually or mechanically is a wise precaution. The
intense heat these piles or tops can generate can damage or kill the roots
and cambium layer and scorch the crowns of nearby trees. Continuing to
burn on a two or three year rotation, using growing season and dormant
season burns, should control the hardwood sprouting and most of the pine
regeneration. When the woody understory is under control, the next step
is to remove the pine component in a final harvest. Following the harvest
and prior to replanting, site preparation is typically needed to remove
unmerchantable hardwoods and pines. The method of site preparation should
be chosen with the level of residual competition and the presence or absence
of desired groundcover species in mind. If the fire has done its job well,
the woody competition should be minimal and any residual groundcover should
have begun to express itself. Fire should be a part of the site preparation
process to control Pales
weevils. Post-planting control of hardwood sprouts might be desirable
and can be achieved by directed spray with foliar active herbicides or
spot treatments with hexazinone products. Appendix II contains a summary
of appropriate forest herbicides and recommendations for their use. Restoration
of understory vegetation is likely achievable through repeated use of
fire, particularly growing season fire, throughout the rotation unless
the site was in cultivation for an extended period prior to becoming reforested.
If, after several years, the understory has not recovered, it may be necessary
to artificially supplement it with seed or seedlings.
Another approach, less often employed, is to leave a portion
(no more than 10 ft2/A of basal area (BA)) of the loblolly or shortleaf
pine stand intact after the pine harvest and underplant with longleaf
seedlings. This would create a two-aged stand and would help provide fuel
for subsequent fires. There are several cautions, however. There is evidence
that even as little as 10 ft 2 /Acre BA can significantly retard growth
of the new stand. More importantly, there may not be adequate pine fuel
to carry sufficiently hot fires to control the prolific loblolly or shortleaf
seedlings sure to result from this technique. These seedlings can be important
competitors for the longleaf and choke out desirable understory vegetation
if not controlled. The more likely outcome of this approach is the creation
of a mixed species pine stand.
Back to Steps to
Restoration
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