Southeastern conifer forests
The Southeastern conifer forests span the coastal plain of the southeastern USA, extending across southeastern Louisiana, southern Mississippi, southern Alabama, central and southern Georgia, and the Florida panhandle and Florida upper peninsula. This ecoregion is the largest conifer forest ecoregion east of the Mississippi and the second largest coniferous ecoregion in the continental USA (second to North Central Rockies Forests). The majority of the land area of this ecoregion falls within the state of Florida.
The Southeastern conifer forests were dominated by relatively open tall stands of long-leaf pine (Pinus palustris) with an understory of wiregrass (Aristida stricta). The open nature of the mature long-leaf pine stands and the frequency of understory fires helped maintain perhaps the richest temperate herbaceous flora on Earth. Unfortunately, virtually all of the mature long-leaf pine forests are gone, with remaining stands being restricted a small number of isolated sites.
Because of the human-induced disappearance of the long-leaf pine forests and its subsequent replacement by mixed hardwood forest, some controversy surrounds the classification of this ecoregion. We follow Ware et al. and many others in viewing this ecoregion as a conifer forest maintained by fire. In fact, this ecoregion is part of a mosaic of vegetation types that grade from long-leaf pine forests (or sandhill communities), to pine savannas, flatwood habitats (pine forests with woody understories), and xeric hardwood communities. Fire regimes largely determine the areal extent of these communities; high frequency, low-intensity fire regimes favor the maintenance of the once-dominant long-leaf pine and wiregrass communities.
The biological diversity of this ecoregion is virtually unparalleled in North America. The Southeastern Conifer Forests were a refugium during the Pleistocene and a major area of adaptive radiation of amphibians, reptiles, and vascular plants. Tree diversity and endemism is highest in this ecoregion, totaling 190 species with 27 endemics. The Southeastern Conifer Forests also rank among the top ten ecoregions in richness of amphibians, reptiles, and birds and among the top ten ecoregions in number of endemic reptiles, amphibians, butterflies, and mammals. The wiregrass understory contains some of the richest herbaceous floras in the world with a single stand containing as many as 200 species. Kartesz lists 3417 species of native herbaceous and shrub species, and among the highest levels of endemism found in North America.
Mature long-leaf pine forests are of particular importance to endangered species such as the red-cockaded woodpecker (Picoides borealis) and the declining gopher tortoise (Gopherus polyphemus). The gopher tortoise is an important keystone species of this ecoregion--nearly 400 species of animals use the burrows of tortoises during various stages of their life cycle. Not surprisingly, many federally listed species are native to long-leaf pine forests communities.
Suppression of natural fire regimes has shifted vegetation to hardwood forests. This unnatural management practice has altered plant communities across the ecoregion and threatens the long-term persistence of many fire-dependent species.
Habitat Loss and Degradation
Over 98 percent of this habitat is now gone in the southeastern section of this ecoregion, much having been converted to agriculture or tree farms. Remaining habitat is limited to fragments and degraded larger patches. Since the middle of this century, long-leaf pine forests have been cut at a rate of 525 square kilometers/year (130,000 acres/year) and replaced with monoculture plantations of slash pine (Pinus elliottii). Slash pine plantations support less diverse species assemblages than the original long-leaf pine habitats.
Among the plant communities found within this ecoregion, the long-leaf pine forests are among the most heavily converted and threatened. Close behind are the mixed conifer and hardwood forests and all upland communities. The least affected habitats are tidal marshes; most other wetland habitats have been moderately affected by conversion. Besides agriculture and pine plantations, fire suppression and suburban sprawl have also resulted in habitat conversion.
Remaining Blocks of Intact Habitat
Several relatively large blocks of intact habitat remain, as well as a number of smaller patches. Some of the best conserved are on military bases. Important blocks in order of decreasing size include:
- Eglin USAir Force Base - western Florida panhandle
- Apalachicola National Forest - northern Florida
- Osceola National Forest - northern Florida
- Ordway Preserve (U. of Florida) - northern Florida
- Desoto National Forest - southern Mississippi
- Okefenokee National Wildlife Reserve - southern Georgia
- St. Marks National Wildlife Refuge - northern Gulf coast of Florida
- Lower Suwannee National Wildlife Refuge - northern Gulf coast of Florida
- Ocala National Forest (only a small part is natural) - north central Florida
- Conecuh National Forest - southern Alabama
- Blackwater State Forest - northwestern Florida panhandle
- Withlacoochee State Forest - central Gulf coast of Florida
- Grand Bay Savannah - southwestern Alabama Gulf coast.
Restoration of habitat in these units would boost the total area of intact habitat to about twelve percent of the ecoregion.
Degree of Fragmentation
Although much of the ecoregion has been converted and exists as isolated fragments, there are a number of undammed rivers with undamaged riparian corridors, because flood regimes have prevented the development of riparian areas. The entire coastline extending into the adjacent Western Gulf Coastal Grasslands  is critical for migratory birds.
Degree of Protection
According to Ware et al., unless concerted action is taken, the end is in sight for this old growth community that has evolved over the millennia and dominated the southeastern Coastal Plain for at least 5000 years. Longleaf pine, wiregrass, the associated oaks, and herbaceous species, and the animals uniquely adapted to taking advantage of the fire-adapted vegetation......may not be with us into the next century. Red-cockaded woodpeckers are considered by some to be the flagship animal species of this community, as longleaf pine and wiregrass are the flagship plants of the woody and herbaceous communities. The authors point out that only 25 percent of the small amount of intact long-leaf pine forests is on public lands under some form of protection.
The greatest challenge to conserving a fraction of this original ecosystem is to manage the 2 to 3 percent of the landscape for maintenance of 100 percent of the original diversity of species and habitats once contained within long-leaf pine forests. Ware et al. illustrate the locations of 37 sites containing remnants of the long-leaf pine communities and mature southern mixed hardwood forests. Most of these sites are small, and quite isolated. Within the ecoregion, the best opportunities for conservation in the short term occur in: Blackwater River State Forest; Eglin Air Force Base; several Florida state parks (especially Wekiwa Springs, Torreya, Gold Head Branch, and San Felasco Hammock); the University of Florida's Ordway Preserve; and the Nature Conservancy's Janet Butterfield Brooks Preserve. Cox et al. propose a series of Strategic Habitat Conservation Areas, covering approximately 20,000 km2, that contain critical habitats and species assemblages that currently lack formal protection.
Types and Severity of Threats
The major types of conversion threats are: 1) fire suppression due to concerns about air quality; 2) highway development; and 3) urban sprawl and suburban development. Florida remains one of the fastest growing states in the United States. The major degradation threat is from introduced species. Perhaps the most serious problem is the spread of kogon grass (Imperata cylindrica), an Asian native, that is replacing the native herbaceous understory and is virtually impossible to eradicate. The major threats in the form of wildlife exploitation are illegal hunting of fox squirrels (Sciurus niger) and black bears (Ursus americanus), collection of herpetofauna and destruction of poisonous snakes. In sum, this ecoregion is considered to be under high threat. We chose not to elevate the conservation status of this ecoregion from endangered to critical because its score for snapshot conservation status was on the edge of endangered/vulnerable. There are still large areas, that while altered, could become part of an effective conservation program if properly managed for biodiversity.
Suite of Priority Activities to Enhance Biodiversity Conservation
- Prevent remaining sites from being logged or converted to pine plantations, and work towards ensuring that areas designated as Strategic Habitat Conservation Areas be granted formal protection.
- Give greater emphasis in an ecoregion conservation plan to create at least one large long-leaf pine forest reserve of at least 5,000 km2 in which this ecosystem can be properly restored and maintained through ecologically sound burning practices.
- Manage remaining sites properly by using controlled burns to maintain fire-dependent communities. Federal agency land managers, especially U.S. Forest Service, Department of Defense, and U.S. Fish and Wildlife Service, will be required to design and implement burning practices that may vary from site to site in order to support the full spectrum of species that require different burning regimes. The right to burn natural vegetation should be assured for land managers and owners to encourage more natural fire management techniques and procedures. Related recommendations are: phase out human-induced winter burns and replace them with growing season burning, minimize fire lane building, restore fire lanes after fire has occurred, and relocate or reduce the soil-destructive aspects of fire lane building.
- Identify core areas and corridors (see SE Wildlands Project documents). An important acquisition is the Pinhook Swamp (60-70,000 acres), which would be purchased to connect the Osceola National Forest (Florida) and the Okefenokee National Wildlife Refuge (Georgia).
- Track recovery of the red cockaded woodpecker in the region. Survey forests in which the woodpecker is found and promote appropriate burns in these areas to improve woodpecker habitat. Monitor emergency ban which was placed on clear cutting within 1.2 km (.75 miles) of active and inactive woodpecker colonies.
- Identify additional biodiversity hotspots and develop and implement plans to protect them.
- Track and influence the management of public lands in the region via public land trustees, who work with state resource agencies to make management decisions for state lands, and revisions of National Forest Plans. National Forest Plans govern the management of federal lands, and are revised every decade. Groups that review and comment upon these plans in November, 1996, will promote such issues as: endangered species recovery, biodiversity maintenance, ground cover maintenance and management, restoration and maintenance of native species, and fire management.
- Block an amendment to the Defense Authorization Bill, now being considered by Congress, which would transfer 360 square kilometers (88,000 acres) of the Kisatchee National Forest to the Department of the Army. The amendment is supported by Congressmen Breaux and Johnston, because it would expand Fort Polk and possibly prevent it from being closed, but is opposed by environmental and citizens' groups. The amendment is the only issue holding up passage of the Defense Authorization Bill at this time.
- Develop a strategy to address and combat chip milling in the southeast forests. This process is used to make paper, and involves the clear-cutting of large tracts of forest, which are processed in newly constructed chip processing factories. Until recently, this process was only a problem in the western United States.
- Identify the type and level of recreation that is compatible with the continued survival and health of wildlife.
- Map the location of roads, obliterate unused forest roads, and prevent unnecessary road building.
Recommendations are based in part on opinions of the authors of this profile and conversations with Sarah Craven (Southeast regional office of the Sierra Club, (205) 933-9111) and Judy Hancock (Public Lands Chair for the Sierra Club in northern Florida, (904) 752-5886).
- Alabama Natural Heritage Program
- Alabama Wilderness Association
- CARL Program (in Florida)
- Coastal Plains Institute & Land Conservancy
- Florida Natural Areas Inventory
- Georgia Department of Natural Resources
- Georgia Natural Heritage Program
- Louisiana Natural Heritage Program
- Mississippi Natural Heritage Program
- National Audubon Society, Southeast Regional Office
- The Nature Conservancy
- The Nature Conservancy - Southeast Regional Office
- The Nature Conservancy of Alabama
- The Nature Conservancy of Florida
- The Nature Conservancy of Georgia
- The Nature Conservancy of Louisiana
- The Nature Conservancy of Mississippi
- Sierra Club, North Florida Representative
- Sierra Club, Southeast Regional Office
- The Wilderness Society, Southeast RegionalOffice
- Wildlife Resources Division
Relationship to other classification schemes
The Southeastern conifer forests are demarcated from the Southeastern mixed forests to the north by vegetation and elevation (the fall line of the Atlantic piedmont). The latter ecoregion is more dominated by oaks and occurs on the piedmont rather than the coastal plain. Omernik and Bailey both extend this ecoregion further west along the Gulf Coastal Plain and north along the Atlantic Coastal Plain, respectively. We divided these coastal plain units into three because: 1) the Gulf Coastal Plain Grasslands and the Mid-Atlantic Coastal Forests contain a mosaic of habitat types that distinguish them from the long-leaf pine dominated forests, 2) the biologically distinct wire-grass communities disappear in the coastal areas west of the boundary we have delineated, replaced by big bluestem grass understories more typical of the central grasslands ecoregions, and 3) conservation strategies for these three units would be unwieldy if managed as a single large unit that would essential span the entire coastline from eastern Texas to Virginia.
Additional information on this ecoregion
- To see the species that live in this ecoregion, including images and threat levels, see the WWF Wildfinder description of this ecoregion.
Disclaimer: This article or contains some information that was originally published by the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth have edited its content and added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.