Once the pride of the South, old-growth longleaf pine forests almost gone
GAINESVILLE, Fla. — Old-growth stands of longleaf pine, the tree that once dominated the Southern landscape and still provides habitat for dozens of threatened species, have all but vanished, according to a study by a University of Florida researcher.
Of the estimated 60 million acres of virgin pine forest that blanketed the Southeast when the first European settlers arrived, as little as 12,000 acres remain, said Morgan Varner, a doctoral candidate in interdisciplinary ecology at UF’s Institute of Food and Agricultural Sciences.
“Everybody knows about the old-growth forests in the Northwest: people don’t seem to realize that there’s old growth in the South that needs protecting,” said Varner, an author of a study of longleaf pine forests published in the April issue of the quarterly Natural Areas Journal.
Massive forests of longleaf pine once covered a broad swath of the Southeastern United States, from eastern Texas to Virginia. Typically these older trees grow to heights of 60 to 70 feet, with some specimens living more than 500 years and growing to widths of up to three feet.
Prized for the hard wood at the heart of its oldest specimens, the longleaf became a cornerstone of the early American economy. Its straight, sturdy trunk made an ideal mast, and many of the best specimens of longleaf were cut down for use by the British navy. The tree’s resin-rich wood made it a good source of turpentine, sparking a pine-products industry that thrived until the middle of the 20th century.
America’s love for the longleaf’s wood, combined with the spread of agriculture, cleared away much of the original old-growth forest – and those trees have largely not been replaced. The sprawling tree farms of the modern South are largely planted in faster-growing slash and loblolly pine.
While longleaf itself is far from extinction – stands of longleaf considered young cover about 3 million acres, according to some estimates – Varner said those stands often don’t have the ecological diversity of old-growth forests, which provides habitat for more than 30 endangered plant and animal species.
“The red-cockaded woodpecker is a good example,” Varner said. “This is probably one of the best-known endangered species in the region. Some people even call it the ‘spotted owl of the South.’ And it will only nest in mature trees.”
Until recent years, researchers had only the vaguest notion of just how much old-growth longleaf pine is actually left in the country. In 1997, Varner and John Kush, a research associate at Auburn University, set out to count and catalogue every remaining old-growth stand, interviewing private landowners and managers of conservation land and visiting sites identified as old-growth in earlier scientific papers.
They found only 15 remaining stands, most of them on military bases or other publicly owned lands, some of them as small as a few dozen acres. While most of the sites are managed with conservation in mind, many face indirect pressure from surrounding urban development.
That pressure is linked to the longleaf’s need for fire. A blaze every three to five years is needed to make way for new pine seedlings and clear the forest understory, the researchers say.
“Strange as it sounds, you have to burn the forest to keep it diverse,” Kush said. “After a burn, you typically see an explosion of plant species and wildlife. But that doesn’t make sense to most people, and when you have a forest near a residential area, there’s a lot of pressure not to do prescribed burns.”
Without prescribed burns, the researchers say, the forest can build up too much fuel, so that when fire does come, it’s intense enough to kill even the oldest of trees.
Varner said there may be yet undocumented stands of old growth around the south: his study lists six rumored old growth sites totaling roughly 1,600 acres that so far haven’t been investigated. He says any private landowners may be holding on to small patches of old-growth forest or even selling the timber from old-growth stands without knowing it.
“One of the first sites I visited during this study had just been clear-cut when I arrived,” Varner said. “Some of the stumps had 300 rings. It was a sad thing to see.”
The changing demographics of the South are making privately-owned tracts of longleaf forest harder to find and preserve, said Rhett Johnson, co-director of the Longleaf Alliance, a coalition of groups that promote preservation of both old-growth and younger longleaf stands. The region is losing the last generation of landowners who recognize longleaf forest and understand its importance, Johnson said.
“There are landowners who say ‘I want my children to see woods like we had when I grew up,’” Johnson said. “But those people are in their 70s, or older. Their children have moved on to Atlanta or some other urban location, and they don’t know the land the way their parents do.”