- CONSERVATION OF THE ENDANGERED PINUS PALUSTRIS ECOSYSTEM - 59

Applied Vegetation Science 9: 59-66, 2006© IAVS; Opulus Press Uppsala.

AbstractQuestion: Can the geographic patterning of endemic plantspecies inform reserve selection in a region of high ende-mism?Location: The southeastern Coastal Plain of North America,focusing primarily on the imperiled Pinus palustris (longleafpine) ecosystem.Methods: We documented the high level of plant endemismin the region, and characterized the endemic taxa into distribu-tional subregions.Results: A total of 1630 plant taxa are endemic to the CoastalPlain, a large proportion of which are endemic to phyto-geographical subregions within the Coastal Plain, with par-ticularly large numbers of narrow endemics occurring in theEast Gulf Coastal Plain and Florida Peninsula.Conclusions: This pattern of local endemism presents chal-lenges in conserving the full biota of the region: a reservesystem focusing on few and large conservation areas hastheoretical benefits for long-term management and viability,but will fail to capture many local endemics. We propose thatthe dispersed distribution of endemic species will require amixture of large core reserves and smaller satellite reserves.

Keywords: Biodiversity; Biogeography; Florida; Longleafpine; Mid-Atlantic Coastal Plain; Southeastern North Ameri-can Coastal Plain.

Nomenclature: Kartesz (1999) with minor exceptions andmodifications and updates from the taxonomic literature.

Conservation of the endangered Pinus palustris ecosystembased on Coastal Plain centres of plant endemism

Sorrie, Bruce A.1* & Weakley, Alan S.2

1North Carolina Natural Heritage Program, Office of Conservation and Community Affairs, 1601 MSC, Raleigh, NC27699-1601, USA; 2University of North Carolina Herbarium, North Carolina Botanical Garden, University of North

Carolina, Campus Box 3280, Coker Hall, Chapel Hill, NC 27599-3280, USA; weakley@unc.edu;*Corresponding author; E-mail bsorrie@earthlink.net

Introduction: Endemic areas in North America

The world’s biota is unevenly distributed spatially,and scientists and conservationists are interested in un-derstanding this unevenness for scientific and appliedconservation purposes. One common and valuable ap-proach to measuring biodiversity and studying patternsof biodiversity distribution is to analyse geographicpatterns of endemism, richness, or uniqueness of bio-logical diversity (see for instance Barthlott et al. 1996,1999). In North America, recent efforts to look at pat-terns of plant endemism include Stein et al. (2000)a, b;Chaplin et al. (2000), Ricketts et al. (1999) and Thorne(1993). For their purposes, these authors have describedbroad patterns of endemism and richness by physio-graphic province or ecoregion, and made little effort todetail and compare the actual numbers of taxa (species,subspecies and varieties). Kartesz (1999) includes in-formation on North American endemics by state andprovince, but this information is not very meaningfulsince it is based on artificial political boundaries. De-tailed information on the endemism of a given floristicprovince or ecoregion has been difficult to ascertain,because most distributional information is gathered bypolitical units, and is also not readily available digitallyfor aggregation and analysis.

The state of California is justifiably famous as one ofthe biodiversity hotspots in North America, with 4844native species of vascular plants (Hickman 1993). Nota-bly high are totals for endemic plant genera (25), en-demic species (1416), and endemic subspecies & varie-ties (737). A more coherent floristic unit is the Califor-nia Floristic Province (southwestern Oregon, Californiawest of the Sierra Nevada crest, and northwestern BajaCalifornia); here the numbers increase to 50 endemicplant genera and 2125 endemic species (Raven & Axelrod1978). Another area frequently cited as an area of sub-stantial endemism in North America is the AppalachianMountain region. Weakley (in prep.) documents twoendemic plant genera and 165 endemic taxa in the

60 SORRIE, B.A. & WEAKLEY, A.S.

Southern Appalachians (southern Pennsylvania to north-ern Georgia). The Ozark-Ouachita Mountain region,famous for disjunct taxa, harbours no endemic plantgenera and 31 endemic taxa (Zollner in prep.). In thePacific Northwest, Thorne (1993) estimated at least 11endemic plant genera and over 600 species in theVancouverian Floristic Province. For our area of inter-est, the Coastal Plain of southeastern North America,Thorne (1993, p. 138) stated “Endemism is high in theCoastal Plain Province, where the flora contains severalhundred endemic species, several endemic genera, andone endemic family, the monotypic Leitneriaceae. Be-cause of repeated Pleistocene inundations, it has a youngflora recruited largely from the more ancient Appala-chian Province, and to a lesser extent from the WestIndian Province to the south and the North AmericanPrairies Province to the west. Although many of thefloristic elements are apparently of very recent origin,many presumably archaic genera are represented”.

Within North America, the Atlantic and Gulf CoastalPlain (hereafter ‘Coastal Plain’) is one of the largestnatural physiographic regions. Extending as a narrow tobroad strip from southeastern Massachusetts to southFlorida, south Texas, and eastern Tamaulipas, Mexico,the area encompasses roughly 1 166 000 km2, or 8% ofthe North American land mass (Fig. 1). While regardedby many as biologically diverse, the Coastal Plain lacksregion-wide documentation of its flora and fauna. Anumber of recent publications within the disciplines ofbiodiversity and conservation treat various portions of theCoastal Plain (Abell et al. 2000; Davis & Heywood 1997;Flatheret al. 1998; Lydeard & Mayden 1995; MacRobertset al. 2002; Barthlott et al. 1996, 1999; Olson & Dinerstein1998; Ricketts et al. 1999; Stein et al. 2000). However,none of these works takes the broad view of the CoastalPlain as a whole, and as a result the region’s biota remains

understudied and undervalued from a conservation per-spective. In this paper we more thoroughly assess anddocument endemism in the Coastal Plain, look at geo-graphical patterns within it, and, focusing on the Pinuspalustris ecosystem, assess the conservation implica-tions of the distribution of endemics in this province.

Methods

We updated the baseline data developed by Sorrie &Weakley (2001) by additional review of the taxonomicand floristic literature covering southeastern NorthAmerica. The literature reviewed includes major floris-tic works and checklists (Gann et al. 2002; Godfrey &Wooten 1979, 1981; Kartesz 1999; McAvoy & Bennett2001; Radford et al. 1968; Small 1933; Turner et al.2003; Weakley 2003; Wunderlin & Hansen 2003). Wehave reviewed hundreds of taxonomic and floristic pa-pers, too numerous to cite here, but a list is availableupon request. We have also conducted supplementarydistributional studies involving more than twenty her-baria (A, AMES, AUA, DUKE, FLAS, FSU, GA, GH,IBE, LSU, MISSA, NCSC, NEBC, NCU, NLU, US,USA, USCH, SWSL, VSC, VDB at BRIT, and severalprivate herbaria) to verify distributions to the countylevel of the rarer Coastal Plain taxa – those ranked G1,G2, or G3 by NatureServe (Anon. 2003; Sorrie &Weakley in prep.).

We then divided the Coastal Plain into eight majorsubunits, based on biogeographic and physiographicconsiderations, similar to those developed by Bailey(1996) and modified by The Nature Conservancy forconservation planning (Groves 2003). We additionallycharacterized the endemic species’ distributions withtwo additional areas outside the Coastal Plain, where anumber of Coastal Plain endemic species occur as raredisjuncts. We characterized each of the endemic speciesas to whether they are obligately associated with thePinus palustris ecosystem, defined as being taxa that arerestricted to P. palustris communities or in closelyassociated, fire-maintained, embedded communities(such as depression ponds, seepage bogs, bayheads,etc.). As our primary interest was the P. palustris eco-system, we then used the subset of associated taxa toanalyse the degree to which Coastal Plain endemics arewidespread in the Coastal Plain – what might be termed‘broad Coastal Plain endemics’ – or limited to only oneor a few of the Coastal Plain subunits – what might betermed ‘narrow Coastal Plain endemics’. Using one ofthe subregions (the Mid-Atlantic Coastal Plain) as anexample, we then assessed the degree to which largefederal and state conservation areas successfully cap-ture the endemic flora.

Fig. 1. The Coastal Plain (stippled area) of southeastern NorthAmerica, defined by the inland junction of Cretaceous depos-its with older Paleozoic formations.

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Results

Coastal Plain plant endemism

According to an update through 2003 on the statis-tics of Coastal Plain endemics presented by Sorrie &Weakley (2001), 1630 taxa – 1370 species and 260additional infraspecific taxa – plus 48 endemic gen-era, are unique to the North American Coastal Plain.Compared with the ca. 6100 taxa native to the CoastalPlain, the rate of endemism would be 26.7%.

The Coastal Plain is clearly of enormous impor-tance to the continent as an evolutionary source andtemporal refugium of vascular plants and a majorcentre of endemic biodiversity. The work of describ-ing new taxa has continued unabated during the past30 years: at least 200 new taxa were described in theCoastal Plain during the 20-year period from 1975 to1994 (Hartman & Nelson 1998).

It may seem incongruous that the relatively flatand featureless Coastal Plain should support suchhigh numbers of native plants and endemics. TheCoastal Plain has few obvious geographic dividers,has very subdued topography (the maximum eleva-tion is less than 244 m), is of relative geologic youth(substrates are mostly unconsolidated sediments de-posited from erosion of rocks in the Appalachian andOzarkian highlands), has an absence of strikingedaphic factors (such as serpentine geology), and hasa relatively homogeneous temperate climate through-out (Fenneman 1938; Walker & Coleman 1987).

Nevertheless, some factors that are responsiblefor the high richness and endemism of the CoastalPlain flora can be identified, including:

1. Soil diversity is high: eight of the ten ordersrecognized worldwide occur in the coastal plain. SoilpH (an important though crude indicator of plantsubstrates) varies from 3 to 8.5. Soil textures includeclays, coarse sands, calcareous and siliceous rocks,and peats.

2. Plant communities reflect a very broad range ofsubstrate type and texture, rainfall pattern, nutrientavailability, hydrology and chemical composition.Thus, communities have adapted to conditions vary-ing from harshly xeric to purely aquatic, and frominland to maritime. Moreover, community turnovermay occur rapidly along pronounced gradients(Christensen 2000; Peet & Allard 1993).

3. Many plant communities have been shaped byfrequently recurring fire – the Coastal Plain has thehighest incidence of lightning strikes on the continent– creating arrested succession or fire disclimax situa-tions which favor speciation among herb and shrubgrowth forms (Komarek 1974; Platt 1999).

4. Despite its relative geological youth (early Ter-tiary, ca. 50 million years before present), the CoastalPlain south of New Jersey has never been glaciatedand undoubtedly acted as a refugium for more north-ern taxa during the Pleistocene and other glacial ep-ochs. Ocean inundations have also been a feature ofCoastal Plain evolution, but not all of the region wascovered during any one advance. Thus, for very longperiods at least some portion of the region was avail-able for colonization and speciation. We think ithighly unlikely that such ancient and highly distinctgenera as Ceratiola, Chrysoma, Dionaea, Franklinia,Leitneria, Lophiola, Pyxidanthera, Rhododon, andSerenoa (to name just some of the 48 endemic gen-era) could have originated anywhere but on the CoastalPlain.

5. The same time spans mentioned above haveallowed for the immigration of numerous taxa (somesuccessful, some not) from the continental tropics,the Caribbean, the Appalachians, the midwestern prai-ries, and the dry Southwest. As climatic changes haveoccurred, these periodic immigrations from all direc-tions have provided genetic stock for speciation. Un-doubtedly many of these immigrants later becameextinct, but others have persisted in a small area orspread more generally in the Coastal Plain.

Sorrie & Weakley (2001) defined 27 patterns ofendemism within the North American Coastal Plain,including disjunctions to the Caribbean basin, to mari-time Canada, and to inland sites. These patterns fol-low natural geographic, physiographic, or floristicboundaries and delimit the ranges of moderate tolarge numbers of taxa which co-occur. The geographi-cal boundary of each pattern outlines a center ofendemism to which a unique suite of taxa is re-stricted, or nearly so. For example, the Lake WalesRidge in the central Florida peninsula supports 37taxa which are found nowhere else (Huck et al. 1989)and the West Gulf Coastal Plain supports 96 taxavirtually restricted to this region (MacRoberts et al.2002).

To facilitate detailed, species-based analysis ofendemism patterns, we have chosen in this study touse broader geographic units as initial analysis units.These areas take a somewhat more inclusive andbroader view of the distribution of endemics by com-bining related or nested patterns in Sorrie & Weakley(2001). Thus, we here recognize eight subregionswithin the Coastal Plain, plus two major disjunctareas which are presented in the following text-table:

62 SORRIE, B.A. & WEAKLEY, A.S.

1, 2, 3, 4, and 5 and forms the heart of the Coastal Plainin terms of biodiversity and endemism (Sorrie & Weakley2001). Descriptions of the associated plant communitiesand overviews of the ecology of P. palustris can befound in Christensen (2000), Harcombe et al. (1993),Peet & Allard (1993), Platt (1999) and Ware et al.(1993). The Pinus palustris ecosystem encompasses abroad range of community types, ranging from xericPinus-Quercus scrub to mesic flatwoods and wet savan-nas, plus included sinkhole ponds, Taxodium depres-sions, and shrub pocosins. As indicated above, the physi-cal and edaphic diversity of the region provided condi-tions for broad-scale speciation. Of the 1630 total vas-cular plant taxa endemic to the entire Coastal Plain,1000 are obligate associates of the Pinus palustris eco-system and occur wholly (or nearly so) within the rangeof P. palustris. Note that in all subregions we tally onlythe taxa associated with the Pinus palustris ecosystem.

Table 1 shows the numerical distribution of endemictaxa among the five subregions occupied by Pinuspalustris. Only 11% of taxa occur in all five subregions,whereas 35% occur only in one subregion, indicatingthat a large proportion of endemics occupy small rangesand may be considered narrow, subregional endemics.Of the 1000 taxa, 54% occur in only one or two of thefive subregions, suggesting that the Pinus palustris eco-system and the Coastal Plain have remarkable localendemism, especially considering the superficial homo-geneity of the ecoregion.

It is of interest to further analyse the degree to whichendemics are restricted to one or several of the subregions,

Fig. 2. Distribution of Pinus palustris in the southeasternUnited States (after Ware et al. 1993). Stippled area: coreregion where the landscape was dominated by the species.Dotted line: area of discontinuous or disjunct occurrences ofP. palustris.

1. Mid-Atlantic Coastal Plain, from southeastern Vir-ginia to southern South Carolina.2. South Atlantic Coastal Plain, from central Georgia tonorthern peninsular Florida.3. Temperate central Florida peninsula (including theLake Wales Ridge).4. East Gulf Coastal Plain, from southwestern Georgiaand the Florida Panhandle west to southeastern Louisi-ana.5. West Gulf Coastal Plain, from western Louisiana toeastern Texas, southern Arkansas, and southeasternOklahoma.6. Northeast Coastal Plain, from the Delmarva Penin-sula of Delaware, Maryland and Virginia, north to Mas-sachusetts and southern Nova Scotia.7. Subtropical southern Florida peninsula.8. Southern Texas to eastern Tamaulipas, Mexico (theTamaulipan Scrub region).9. Inland disjunctions (Cumberland Plateau, SouthernAppalachian bogs, Great Lakes shores, etc.).10. West Indies disjuncts (especially the northern Baha-mas, and northwestern Cuba), Central America (espe-cially Belize), and Bermuda.

The Pinus palustris ecosystem – the core of theCoastal Plain

As shown in Fig. 2, Pinus palustris occupies a broadswath from southeastern Virginia south to central Floridaand west to east Texas (Ware et al. 1993). This largearea encompasses most or all of Coastal Plain subregions

Table 1. Narrowness of endemism of the 1000 Coastal Plainendemic taxa closely associated with the Pinus palustris eco-system. The second column tallies the number of taxa whichoccur in all five subregions in the distribution area of P.palustris (see Table 2), in any four subregions, etc.

No. of No. of endemic taxa % endemicssubregions within subregions within subregions

5 subregions 109 11%4 subregions 188 19%3 subregions 155 16%2 subregions 195 19%1 subregion 353 35%

Table 2. Distribution by Coastal Plain subregion of narrowlyendemic taxa (taxa endemic to one subregion).

Coastal Plain subregion Number of endemics

East Gulf Coastal Plain 125 taxaFlorida Peninsula 122 taxaMid-Atlantic Coastal Plain 44 taxaSouth Atlantic Coastal Plain 33 taxaWest Gulf Coastal Plain 29 taxa

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or are rather evenly distributed across the five subregions.The East Gulf Coastal Plain and Florida Peninsula havethe highest numbers of single-subregion endemics (Ta-ble 2), though substantial numbers of narrow endemicsare also present in the other three subregions (Mid-Atlantic Coastal Plain, South Atlantic Coastal Plain, andWest Gulf Coastal Plain). This confirms a pattern longobserved by students of the Coastal Plain flora: that theEast Gulf Coastal Plain and Florida Peninsula are in asense the ‘core Coastal Plain’ and have the highestlevels of endemism (Gentry 1986; Harper 1907; James1961). This is perhaps not surprising, considering theirgeographic position, which is simultaneously central inthe Coastal Plain (along its expanse from northeast tosouthwest) and peripheral (at the outer edge of theCoastal Plain and were perhaps best able to serve as arefugium of evolved endemics).

Other Coastal Plain taxa are less narrowly distrib-uted. If one considers taxa that are endemic to twosubregions, the pattern established above remains (Ta-ble 3). The East Gulf Coastal Plain (which shares a totalof 125 taxa with other subregions) and Florida Penin-sula (88 shared endemics) are once again the ecoregionswith the largest number of endemics, with the SouthAtlantic Coastal Plain (78 shared endemics), Mid-At-lantic Coastal Plain (36 shared endemics), and WestGulf Coastal Plain (23 shared endemics) trailing. Thelarge number of South Atlantic Coastal Plain sharedendemics is explained by its central position and itsability to combine with the Florida Peninsula, East GulfCoastal Plain, and Mid-Atlantic Coastal plain. The WestGulf Coastal Plain’s isolation by the MississippiEmbayment from the other Pinus palustris subregions isapparent in its near-absence of shared endemics: it sharesonly 23 taxa with the East Gulf Coastal Plain but no taxawith other subregions. Moreover, speciation within theWest Gulf Coastal Plain has inordinately favoured taxathat have adapted to xeric habitats (MacRoberts et al.2002), a reflection of the region’s strongly decreasingrainfall gradient from east to west.

Conservation of the Pinus palustris ecosystem

Once the dominant vegetation across 38 million ha,Pinus palustris communities now occupy only 3% of thatarea in natural condition (Frost 1993). Given the reducedarea and the very high number of endemic taxa, there isample reason for concern over the future of this ecosys-tem. Criteria necessary for ecosystem viability includefire management, which in turn places an emphasis onrelatively large sized landscapes managed by landownerswith sufficient resources (funding, equipment, trainedpersonnel) to conduct prescribed burns. Effective firemanagement requires knowledge of optimal fire frequency,timing of fire, and division of a site into burn units(Beckage & Stout 2000; Glitzenstein et al. 2003; Komarek1974; Sparks et al. 1998). Proper application of fire canbe crucial to viability of rare plant and animal populations(Gray et al. 2003; Kirkman et al. 1998). Many landown-ers and managers have become skilled at applying pre-scribed burns to small properties, in which whole blocksburn evenly and completely. However, it is now believed(Frost 1998) that incomplete or patchy burns more closelymimic historical conditions, when lightning-set wildfiresand fires set by American Indians swept across landscape-sized parcels. Patches of unburned or incompletely burnedhabitat allow survival of some species, including subcanopyhardwoods, which require longer fire intervals. Moreover,insect guilds, which are essential for plant pollination, asfood items for many animals, and for ecosystem nutrientrecycling, may be adversely harmed by thorough burns.These issues aside, the necessary combination of fire man-agement and viable landscapes points to large publiclyowned lands and private preserves.

Federal lands that are critical to the conservation ofthe Pinus palustris ecosystem fall into four major cat-egories: National Forests (owned by the U.S. Depart-ment of Agriculture), military installations (U.S. De-partment of Defense), National Wildlife Refuges (U.S.Fish and Wildlife Service), and miscellaneous. Togetherthese federal lands constitute the largest remaining blocksof Pinus palustris ecosystem in the Coastal Plain.

National Forests include Croatan in North Carolina; FrancisMarion in South Carolina; Apalachicola, Ocala, and Osceola in Florida;Conecuh in Alabama; De Soto and Homochitto in Mississippi; Kisatchiein Louisiana; and Angelina and Sabine in Texas. Military landsinclude Fort Bragg/Camp Mackall (Army) and Camp Lejeune (Ma-rine Corps) in North Carolina; Fort Jackson (Army) in South Carolina;Fort Benning (Army), Fort Gordon (Army), and Fort Stewart (Army)in Georgia; Avon Park Air Force Range and Eglin Air Force Base inFlorida; Camp Shelby (Army) in Mississippi; and Fort Polk (Army) inLouisiana. National Wildlife Refuges include Carolina SandhillsN.W.R. in South Carolina; Okefenokee N.W.R. in Georgia; LakeWales Ridge N.W.R. and St. Marks N.W.R. in Florida; Grand BayN.W.R. in Alabama and Mississippi; and Mississippi Sandhill CraneN.W.R. in Mississippi. Miscellaneous federal lands include the Sa-vannah River Site (U.S. Department of Energy) in South Carolina andBig Thicket National Preserve (U.S. National Park Service) in Texas.

Table 3. Distribution by Coastal Plain subregion of narrowlyendemic taxa (taxa endemic to two subregions).

Coupled Coastal Plain subregions No. of endemics

Florida Peninsula + East Gulf Coastal Plain 61 taxaSouth Atlantic Coastal Plain + East Gulf Coastal Plain 29 taxaSouth Atlantic Coastal Plain + Florida Peninsula 26 taxaMid-Atlantic Coastal Plain + South Atlantic Coastal Plain 23 taxaFlorida Peninsula + East Gulf Coastal Plain 23 taxaMid-Atlantic Coastal Plain + East Gulf Coastal Plain 12 taxa

64 SORRIE, B.A. & WEAKLEY, A.S.

State conservation lands are also diverse in owner-ship and purpose, ranging from state parks to wildlifemanagement areas to nature preserves. A sampling ofthose important to the Pinus palustris ecosystem in-clude Bladen Lakes State Park, Holly Shelter GameLand, and Sandhills Game Land in North Carolina;Sand Hills State Forest in South Carolina; BlackwaterRiver State Forest, Jennings State Forest, Lake WalesRidge State Forest, and Withlacoochee State Forest inFlorida; Geneva State Forest in Alabama; Marion CountyWildlife Management Area in Mississippi; Sandy Hol-low Wildlife Management Area in Louisiana.

Private landowners generally do not have large enoughparcels to practice ecosystem-level management of P.palustris, but exceptions include The Nature Conserv-ancy, a few research stations, and several local timbercompanies. Examples (not intended to be complete) ofcritical, privately owned Pinus palustris ecosystem areasinclude the Green Swamp and Myrtle Head Savanna inNorth Carolina (The Nature Conservancy); the DisneyWilderness Preserve in Florida (The Nature Conserv-ancy), the Joseph Jones Ecological Research Centre inGeorgia; Tall Timbers Research Station in Florida; T.R.Miller and Crosby lands in Alabama; Crosby Arboretumand Tatum lands in Mississippi; and Sandylands Preservein Texas (The Nature Conservancy).

Are public and private lands truly protected?

The question of what constitutes protection is notstraightforward. There is a lack of hard data on what isthe minimum size needed for viable (long-term) exam-ples of Pinus palustris communities. One major hurdle isthat research needs to be conducted over extended peri-ods – decades – in order to assess effectiveness of man-agement and viability of the community (Platt 1999). Insome cases, fire management has been in place for dec-ades, but there is little or no funding available for habitatmonitoring or for research into community dynamics.

The important federal and state-owned areas listedabove are nearly all ‘multiple use’ areas, and for manyof them there is some level of concern about their long-term conservation status. While multiple-use conserva-tion can be made generally compatible with the conser-vation of the Pinus palustris ecosystem and its endemicbiota, these areas are under periodic threat from politi-cally driven changes in land-use policy that affect themanaging agencies. Military lands are under particularthreat, as political changes and military challenges oc-cur around the world and as the armed services struggleto reconcile conservation goals with increased trainingon fewer installations. The Forest Service finds itselfunder changing and conflicted mandates relative to thebalance between timber production, ecosystem health,

and provision of recreational opportunities. Private con-servation areas are also not immune from policy changesthat may have impacts of the effective conservation ofthe Pinus palustris ecosystem. In the last several years,The Nature Conservancy, the most effective privateconservation organization involved with P. palustrisconservation, has gone through a series of changeswhich have resulted in a new emphasis on divestiture ofpreserves, involvement primarily in landscape-scaleconservation efforts, and ecoregional conservation plan-ning (Groves 2003). These changes may result in TheNature Conservancy working at fewer, larger areas,which has potentially positive and negative effects rela-tive to Pinus palustris ecosytem conservation.

As an exercise, let us consider the protection af-forded endemic plant taxa in the Mid-Atlantic CoastalPlain. An analysis of the conservation status of the 44endemic plants associated with Pinus palustris indicatesthat 28 are well-protected, in the sense of having multi-ple occurrences on well-managed conservation lands(military, national forest, state game land, state forest,private; but see above for caveats), while 16 are poorlyprotected, with few or no occurrences on secure conser-vation lands. It is clear that even in a Coastal Plainsubregion with very significant conservation areas, lo-cal endemics may ‘fall through the cracks’ of the reservesystem.

The implications of narrow endemism

The Coastal Plain’s high diversity of endemics andpattern of substantial local endemism presents someconservation challenges. Conservation planning requiresthat conservation action be directed toward the conser-vation targets, and there has been a general inclinationto treat endemic species as high-priority conservationtargets (Groves 2003). Conservation planning also de-mands that long-term viability of reserves be consid-ered, and a general consensus is that larger reserveshave greater long-term viability and manageability thansmall reserves. In the case of the Pinus palustris ecosys-tem, large size may be a particular important factorbecause of the importance of active fire management,and the correlation between size and ability to safely andeffectively conduct prescribed burning in a landscapewith rapidly increasing human development.

Future protection of the Pinus palustris ecosystemwill call for imaginative new solutions as well as relyingon traditional ones. Outright purchase of additional landby public and private entities will continue. Ideallythese will be contiguous parcels, but even small isolatedparcels may be adequate to protect communities thatnaturally occur as sporadic habitats embedded within

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the larger Pinus palustris landscape; examples are cy-press domes, Carolina bays, and sinkhole ponds. Aslong as the natural processes are protected (no drainageditches or water table alteration), these patchy habitatsare likely to be viable over the long-term. The NatureConservancy has pioneered flexible protection options,such as conservation easements, and these will be in-creasingly useful in the future as land transactions maybecome more complex. Partnerships may also be avaluable protection tool, especially in instances whereno one agency has adequate resources to do the job. Forexample, the largest contiguous block of Pinus palustrisin existence is in southern Alabama and northwesternFlorida. Here, Eglin Air Force Base, Blackwater RiverState Forest, Conecuh National Forest, and the T.R.Miller timber company actually or nearly abut to form amega-landscape that is probably unmatched anywherein the range of Pinus palustris for habitat diversity,ecosystem quality, and numbers of rare species. In thisexample four major kinds of landowners, each withtheir own mandates and objectives, have an opportunityto make a uniquely significant contribution to the sur-vival of hundreds of species while at the same timeretaining the right to train pilots, sell timber, and providerecreation. Similarly, landowners, managers, and citi-zens must increasingly utilize novel protection schemesto protect viable landscapes throughout the range ofPinus palustris . The full suite of P. palustris associatedendemics can only be conserved through a reserve sys-tem that will include viable managed conservation areasat all scales: large core landscapes and selected andcarefully targeted smaller satellite reserves.

Acknowledgements. We wish to thank Frank Gilliam, BobPeet and Bill Platt for their involvement in organizing thissymposium; Steve Orzell and an anonymous reviewer for theirhelpful comments about the manuscript; and Coastal Plainbotanists and Southeastern herbaria for their contributions tothe set of data on which this paper is based.

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Received 28 July 2004;Accepted 9 July 2005.

Co-ordinating Editor: F.S. Gilliam.