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The beauty and the biodiversity of the longleaf pine forest are
well-kept secrets, even in its native South. Yet it is among the richest
ecosystems in North America, rivaling tallgrass prairies and the ancient
forests of the Pacific Northwest in the number of species it shelters. And
like those two other disappearing wildlife habitats, longleaf is also
critically endangered.
In longleaf pine forests, trees grow widely scattered, creating an
open, parklike environment, more like a savanna than a forest. The trees
are not so dense as to block the sun. This openness creates a forest floor
that is among the most diverse in the world, where plants such as
many-flowered grass pinks, trumpet pitcher plants, Venus flytraps, lavender
ladies and pineland bog-buttons grow. As many as 50 different species of
wildflowers, shrubs, grasses and ferns have been cataloged in just a single
square meter.
Once, nearly 92 million acres of longleaf forest flourished from
Virginia to Texas, the only place in the world where it is found. By the
turn of the 2lst century, however, virtually all of it had been logged,
paved or farmed into oblivion. Only about 3 percent of the original range
still supports longleaf forest, and only about 10,000 acres of that is
uncut old-growth—the rest is forest that has regrown after cutting. An
estimated 100,000 of those acres are still vanishing every year. However, a
quiet movement to reverse this trend is rippling across the region.
Governments, private organisations (including NWF) and individual
conservationists are looking for ways to protect and preserve the remaining
longleaf and to plant new forests for future generations.
Figuring out how to bring back the piney woods also will allow
biologists to help the plants and animals that depend on this habitat.
Nearly two-thirds of the declining, threatened or endangered species in the
southeastern United States are associated with longleaf. The outright
destruction of longleaf is only part of their story, says Mark Danaher, the
biologist for South Carolina’s Francis Marion National Forest. He says the
demise of these animals and plants also is tied to a lack of fire, which
once swept through the southern forests on a regular basis. “Fire is
absolutely critical for this ecosystem and for the species that depend on
it,” says Danaher.
Name just about any species that occurs in longleaf and you can find
a connection to fire. Bachman’s sparrow is a secretive bird with a
beautiful song that echoes across the longleaf flatwoods. It tucks its nest
on the ground beneath clumps of wiregrass and little bluestem in the open
under-story. But once fire has been absent for several years, and a tangle
of shrubs starts to grow, the sparrows disappear. Gopher tortoises, the
only native land tortoises east of the Mississippi, are also abundant in
longleaf. A keystone species for these forests, its burrows provide homes
and safety to more than 300 species of vertebrates and invertebrates
ranging from eastern diamond-back rattlesnakes to gopher frogs. If fire is
suppressed, however, the tortoises are choked out. “If we lose fire,” says
Bob Mitchell, an ecologist at the Jones Center, “we lose wildlife.”
Without fire, we also lose longleaf. Fire knocks back the oaks and
other hardwoods that can grow up to overwhelm longleaf forests. “They are
fire forests,” Mitchell says. “They evolved in the lightning capital of the
eastern United States.” And it wasn’t only lightning strikes that set the
forest aflame. “Native Americans also lit fires to keep the forest open,”
Mitchell says. “So did the early pioneers. They helped create the longleaf
pine forests that we know today.”
Fire also changes how nutrients flow throughout longleaf ecosystems,
in ways we are just beginning to understand. For example, researchers have
discovered that frequent fires provide extra calcium, which is critical for
egg production, to endangered red-cockaded woodpeckers. Frances James, a
retired avian ecologist from Florida State University, has studied these
small black-and-white birds for more than two decades in Florida’s
sprawling Apalachicola National Forest. When she realised female
woodpeckers laid larger clutches in the first breeding season after their
territories were burned, she and her colleagues went searching for answers.
“We learned calcium is stashed away in woody shrubs when the forest is not
burned,” James says. “But when there is a fire, a pulse of calcium moves
down into the soil and up into the longleaf.” Eventually, this calcium
makes its way up the food chain to a tree-dwelling species of ant, which is
the red-cockaded’s favorite food. The result: more calcium for the birds,
which leads to more eggs, more young and more woodpeckers.
Today, fire is used as a vital management tool for preserving both
longleaf and its wildlife. Most of these fires are prescribed burns,
deliberately set with a drip torch. Although the public often opposes any
type of fire—and the smoke that goes with it—these frequent, low-intensity
burns reduce the risk of catastrophic conflagrations. “Forests are going to
burn,” says Amadou Diop, NWF’s southern forests restoration manager. “It’s
just a question of when. With prescribed burns, we can pick the time and the
place.”
Diop is spearheading a new NWF effort to restore longleaf. “It’s a
species we need to go back to,” he says. Educating landowners about the
advantages of growing longleaf is part of the program, he adds, which will
soon be under way in nine southern states. “Right now, most longleaf is on
public land,” says Jerry McCollum, president of the Georgia Wildlife
Federation. “Private land is where we need to work,” he adds, pointing out
that more than 90 percent of the acreage within the historic range of longleaf
falls under this category.
Interest among private landowners is growing throughout the South,
but restoring longleaf is not an easy task. The herbaceous layer—the
understory of wiregrasses and other plants – also needs to be re-created.
In areas where the land has not been chewed up by farming, but converted to
loblolly or slash pine plantations, the seed bank of the longleaf forest
usually remains viable beneath the soil. In time, this original vegetation
can be coaxed back. Where agriculture has destroyed the seeds, however,
wiregrass must be replanted. Right now, the expense is pro-hibitive, but
researchers are searching for low-cost solutions.
Bringing back longleaf is not for the short-sighted, however. Few of
us will be alive when the pines being planted today become mature forests
in 70 to 80 years. But that is not stopping longleaf enthusiasts. “Today,
it’s getting hard to find longleaf seedlings to buy,” one of the private
landowners says. “Everyone wants them. Longleaf is in a resurgence.”
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