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Sand
pine scrub is a xeric community with a closed to open canopy
of sand pines and a dense understory of oaks and other evergreen
shrubs. Ground layer vegetation is sparse with many
bare sandy patches alternating with dense stands of lichens.
Its soils consist of sandy, acidic, very well drained, nutrient-deficient
soils. Common vegetation in a sand pine scrub community
include sand pine, red bay, myrtle oak, sand live oak, Chapman's
oak, saw palmetto, scrub palmetto, rusty staggerbush, Florida
rosemary, blue huckleberry, staggerbush, fetterbush, wild
olive, blueberry, deerberry, and muscadine grape (Stout and
Marion, 1993). Animals of interest that utilize this
habitat include the gopher tortoise, sand skink, scrub lizard,
and Florida scrub-jay (PruSak, personal observation).
As with other scrub communities, sand pine scrub is fire maintained.
Fires in this community can be either very small and extinguish
rapidly or very large and burn with great intensity. Most
of the scrub vegetation is initially topkilled by intense
fires, but then will often resprout vigorously from existing
roots. Sand pines of all age classes are not fire tolerant,
and are killed outright by these fires. While the fire itself
may kill the adult trees, the heat from this fire acts to
open their cones, releasing the sand pine seeds onto the soil.
These seeds will then germinate anywhere from one to three
years post-fire, resulting in what is termed a "stand replacement"
fire. Any large oaks present within the sand pine scrub community
will be topkilled by the intense fires as well, allowing for
the sand pines to reestablish their dominance in the tree
layer. Fire suppression in this community may result in the
succession of sand pine scrub into a xeric oak hammock. In
the absence of fire mature sand pines may develop heart rot
and die, and healthy sand pine cones may not be stimulated
enough by the latent heat to release their seeds. The resultant
lack of new sand pine seedlings will allow for the oaks to
eventually dominate the landscape. On the other hand, fires
that are too frequent will prevent cone-bearing pines from
maturing by killing off the young pines and will also decrease
the ground cover, eventually altering the fire regime (Stout
and Marion 1993). The natural fire interval for maintaining
sand pine scrub varies widely from 15 to 100 years (TNC, 1995),
and is very site-specific.
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