Many communities have been described in the West Gulf Coastal Plain. These include small isolated prairies, pitcher plant bogs, xeric sandylands, upland monospecific longleaf pine forests, wetland pine savannas, sandstone barrens, baygalls, forested wetlands, palmetto flats, and beech-magnolia forests. Some communities described by early explorers as common in the 19th century no longer exist, e.g., cedar forests and floodplain prairies.
Brief descriptions of the community types are given here, each with pertinent literature. A list of references that are broader in approach, each including information and references on a number of communities, is provided at the bottom.
Xeric Sandylands occur on deep, coarse sands that, because of rapid movement of water through them, produce droughty conditions. Sandylands are characterized by an open over-story that includes scattered pines, oaks and hickory. Lichens are common. Herbaceous species of interest are many West Gulf Coastal Plain endemics, such as large-flowered tickseed, Louisiana yucca, sandhill woollywhite, Reverchon’s spiderwort, and Soxman’s milkvetch.
MacRoberts, B.R., M.H. MacRoberts, and J.C. Cathey. 2002. Floristics of xeric sandylands in the post oak savanna region of east Texas. Sida 20:373-386.
Bog/Pitcher Plant Bog/ Wetland Pine Savanna are wetlands. Pitcher plant bogs occur where hillside groundwater seeps into acid nutrient-poor sandy soils and emerges on hillsides or at stream edges.
Pine savannas occur on flat, sandy soils that drain slowly because of an underlying, semi-porous clay layer. Over-story is generally absent or consists of a few, scattered, often stunted pines, typically longleaf pine. Herbaceous cover is diverse and includes many carnivorous species: sundews, pitcher plants, butterworts, and bladderworts. Orchids are common, as are yellow colic root, pipeworts, club mosses, sedges, and yellow–eyed grasses.
MacRoberts, M.H. and B.R. MacRoberts. 2001. Bog communities of the West Gulf Coastal Plain: a profile. Bog Research Pap. Bot. & Ecol. 1:1-151.
Upland Inland Marshes are fairly common in the post oak savanna region of the West Gulf Coastal Plain. At their edges, they support baygall and bog vegetation, but toward their center characteristic marsh plants take over: sedges, reeds, and wetland grasses; on root matts and in shallower water, ferns and wetland shrubs such as button bush. Peat deposits are often associated with this community, and it is from these deposits that pollen has been obtained that provides information on Pleistocene and Holocene vegetation and climate. These are quaking bogs.
MacRoberts, M.H. and B.R. MacRoberts. 2001. Bog communities of the West Gulf Coastal Plain: a profile. Bog Research Pap. Bot. & Ecol. 1:1-151.
Cypress-Tupelo Swamp is associated with inundated areas and has relatively low floristic diversity. Common species are red maple, buttonbush, ash, tupelos, waterlocust, willows, sycamore, and floating and submersed aquatic plants such as mosquito fern and various duckweeds.
Van Kley, J.E. and D.N. Hine. 1998. The wetland vegetation of Caddo Lake. Texas J. Sci. 50:267-290.
Prairies are one of the world’s rarest but best studied plant communities. Isolated prairies in the West Gulf Coastal Plain are closely related to the Grand Prairies of east central Texas.
Small prairies once occurred throughout the region, but virtually all have been destroyed by agriculture. The few that remain are diverse: tall grasses such as big blue stem and Indian grass, a host of legumes and members of the aster family and rareties such as Mead’s sedge can still be found in them.
MacRoberts, M.H. and B.R. MacRoberts. 2004. West Gulf Coastal Plain prairies: a first approximation at a synthesis. Pp. 5-21. In: The Third Eastern Native Grass Symposium, The North Carolina Botanical Garden, Chapel Hill.
Bottomland Prairie is one of the most frequently mentioned communities by Freeman and Custis in their 1806 account of the Red River expedition. Freeman relates: “We did not wait, but pushed on, through bushs in a kind of Bayou within the Lake, and at last got through the lake, and entered a Bayou, by which we entered a handsome Prairie; the surface of the land was four feet higher than the water of the Bayou; the soil rich, the grass high and luxuriant.” Dunbar and Hunter in 1805 also frequently mentioned prairies along the Ouachita River. Unfortunately, these communities no longer exist, so we cannot know their flora except for two surviving herbarium specimens from the Freeman and Custis expedition: Culver’s root and prairie gentian.
MacRoberts, D.T., B.R. MacRoberts, and M.H. MacRoberts. 1997. A floristic and ecological interpretation of the Freeman and Custis Red River expedition of 1806. Bull. Mus. Life Sci. 12:1-26.
Baygall/Forested Acid Seeps are widespread throughout the West Gulf Coastal Plain and are quite variable. They often originate as groundwater seeps that emerge at head slopes of minor streams and drainages. Soils are usually acidic and saturated. Overstory and midstory typically are mesic to wetland trees and shrubs such as sweetbay magnolia, red maple, American holly, liquidambar, wax myrtle, tupelo, blackgum, and rhododendrons. Catbriar and grape are often common, as are mosses and liverworts and ferns, notably royal, cinnamon, and chainfern. Interesting forbs are reinorchid, scabrid sunflower, and white-top aster.
MacRoberts, B.R., M.H. MacRoberts, and L.S. Jackson. 2004. Floristics of baygalls in central Louisiana. Phytologia 86:1-22.
Upland Hardwood-Pine Forest, of which there are many named types, differs mainly in overstory species composition, but little in understory. The most common oaks today are white oak, red oak, blackjack oak, post oak, shumard oak, and black oak. Common hickories are Texas hickory, bitternut, and mockernut. Sweetgum can also be a dominant canopy species as well as occur in the under or midstory. Dogwood, beautyberry, and sassafras are common in the midstory, and yaupon is ubiquitous especially where fire has been suppressed. In well-burned areas, the herbaceous layer is rich in grasses and forbs.
Bragg, D.C. 2002. Reference conditions of old-growth pine forests in the Upper West Gulf Coastal Plain. J. Torr. Bot. Soc. 129:261-288.
Upland Hardwood Forest/Oak Hickory Forest is typical of the post oak savanna region of the West Gulf Coastal Plain. Its characteristic feature is a mixture of oak and hickory and an absence of pine. The regional proportion of oak to hickory in these forests is much debated. Although this community is traditionally associated with the post oak savanna region of the West Gulf Coastal Plain, it also occurs within the longleaf pine forest and oak-pine-hickory regions.
Marietta, K.L. and E.L. Nixon. 1983. Vegetational analysis of a post oak-black hickory community in east Texas. Texas J. Sci. 35:196-203.
Ward, J.R. and E.S. Nixon. 1992. Woody vegetation of dry, sandy uplands of eastern Texas. Texas J. Sci. 44:283-294.
Mesic Mixed Pine-Hardwood Slope/Upland Forest is not easily separated from upland hardwood-pine forest, into which it grades, and more mesic downslope forests such a beech-magnolia hardwood forest. The distinction among these categories depends on percent of oak cover and on the pine species present. Understory vegetation is quite variable, largely because of site differences in fire history and the invasion of most fire-suppressed areas by shrubby vegetation, particularly yaupon.
Carr, S. 2000. Composition and structure of second-growth pine-oak-forests in northwestern Louisiana. M.S. Thesis.
Beech/Magnolia Hardwood Forest/ Lower Slope Forest is a lower slope community that grades into the previous category. It is typically found in deep ravines with a well-developed canopy of oak, maple, beech, ash, big-flowered magnolia, and some loblolly pine, with little midstory in mature stands. Herbaceous species often include many uncommon species associated with more northern climates, such as bearded shorthusk, toothwort, houndstongue, bloodroot, ladies’slipper, trout lily, witch hazel, Indian pipe, mayapple, clasping goldenrod, basswood, trillium, and bellwort.
MacRoberts, B.R. and M.H. MacRoberts. 1997. Floristics of beech-hardwood forest in east Texas. Phytologia 82:20-29.
Calcareous Forest occurs in the uplands of central and northern Louisiana, often near prairies on side slopes above small creeks. Soils are calcareous clays with high shrink-swell. Characteristic overstory species are several hickories, ash, elm, oak, and loblolly pine. Understory shrubs are redbud, various hawthorns and cherries, deciduous holly persimmon, and rusty viburnum. Herbaceous plants include such relatively uncommon species as lousewort, houndstongue, and cranefly orchid.
Allen, C.M. 1993. Ecological assessment of the forest vegetation of Keiffer Prairie Research Natural Area. Unpublished report, U.S. Forest Service, Pineville, Louisiana.
Riparian Forest, Stream Bottoms, and Stream Sides comprise a set of communities that occur along secondary and tertiary stream courses. Mixed hardwood-pine forests are typical of these habitats. Species composition varies relative mainly to hydroperiod. Baygall species are often present at stream heads, and beech forest may occur on lower slopes with deeply cut perennial streams.
Mundorff, K.T. 1998. Ecological classification of bottomland hardwood forests in east Texas and central Louisiana. M.S. Thesis, Stephen F. Austin State University, Nacogdoches, Texas. 106 pp.
Batture is generally defined as a pioneer community at the edge of rivers. However, in the Red River floodplain in northern Louisiana, batture extends across the floodplain to the uplands, often several kilometers from the river edge. Common woody species include boxelder, pecan, hackberry, roughleaf dogwood, native privet, sycamore, elder, and cottonwood.
Louisiana Natural Heritage Program. 2004. The natural communities of Louisiana. Unpublished report. Department of Wildlife and Fisheries. Baton Rouge, Louisiana. 46 pp.
Bottomland/Floodplain Hardwood Forest is a catchall category that includes the many bottomland and floodplain communities described for the West Gulf Coastal Plain. Most intensively studied in southeastern Texas, floodplain communities are associated with streams and rivers and are dominated by species adapted to periodic inundation, saturation, and adjacent upland runoff. Features common to floodplains include meander channels, natural levees adjacent to channels, oxbow lakes, meander scars, bayous, slight elevation changes, and short geologic life. Various idealized zonal classifications of vegetation have been devised that give the impression of an ordered succession of communities from river edge to uplands, a progression not found for the Red River floodplain of northwestern Louisiana.
Mundorff, K.T. 1998. Ecological classification of bottomland hardwood forests in east Texas and central Louisiana. M.S. Thesis, Stephen F. Austin State University, Nacogdoches, Texas. 106 pp.
Van Kley, J.E. and D.N. Hine. 1998. The wetland vegetation of Caddo Lake. Texas J. Sci. 50:267-290.
Bezanson, D. 2000. Natural vegetation types of Texas and their representation in conservation areas. MS Thesis, Univ. Texas, Austin. 215 pp.
Freshwater Shrub Swamps are lake-edge communities and can be associated with cypress swamps, oxbows, or impoundments. Common woody species are alder, buttonbush, native privet, ash, and willow. Seasonal, floating aquatics such as mosquito fern and various members of the duckweed family may be common.
Van Kley, J.E. and D.N. Hine. 1998. The wetland vegetation of Caddo Lake. Texas J. Sci. 50:267-290.
Interior Salt Flats/Saline Prairies are sparsely vegetated openings covered in places with a thin layer of salt crystals. Their origin may be related to salt domes near the surface. Saline communities are often found in proximity of streams or rivers and may flood in rainy weather. Many salt-tolerant, unusual, and often rare plants occur here; e.g., silver dwarf morning glory, ground fruit, Texas saxifrage, golden hyssop, copper amaryllis, Texas sunnybell, Drummond’s sandwort, san saba pinweed, and flameflower. Mima mounds are common at these sites.
Keith, E.L., J.R. Singhurst, and S. Cook. 2004. Geocarpon minium (Caryophyllaceae) new to Texas. Sida 21:1165-1169.
Mayhaw Flats are virtually unstudied but are found scattered in the uplands and bottomlands in shallow depressions that are water-logged throughout the growing season. Large shrubs or trees, usually less than fifteen meters tall, cover these almost herbaceous- free areas. Common woody vegetation, which is ecologically variable, includes native privet, hawthorns, ash, waxmyrtle, oaks, willow, and water elm.
Sandstone Glade/Barren is a catchall category for many open, often flat, shallow-soiled and sometimes rocky communities that exist throughout the West Gulf Coastal Plain. Shallow soils, fluctuating water supply, and lack of canopy or shrubs suggest stressful conditions for plants, and many species typical of these sites are held in common with saline prairies. Sandstone outcrops are characterized by an exposed sandstone “pavement” with prairie-like soils and prairie-like vegetation. Indicator species are rayless goldenrod, silver dwarf morninglory, fimbry, snowy orchid, slender bluestem, Texas sunnybells, flameflower, and Riddell’s spikemoss. Glades occur on Kisatchie soils and are open, with scattered rocks and a flora more associated with surrounding upland longleaf pine savanna. Drier areas are characterized by white colicroot, three-awn grass, rayless goldenrod, liatris, showy aster, compass plant, dogtooth violet, snowy orchid, and false foxflove. Characteristic wet species found in glades include yellow colicroot, sundew, butterwort, and pinewoods rosepink.
MacRoberts, B.R. and M.H. MacRoberts. 1993a. Floristics of two Louisiana sandstone glades. Phytologia 74:431-437.
MacRoberts, M.H. and B.R. MacRoberts. 1993b. Vascular flora of sandstone outcrop communities in western Louisiana with notes on rare and noteworthy species. Phytologia 75:463-480.
Canebrakes were common in parts of the West Gulf Coastal Plain prior to European occupation of the southeastern United States but have been virtually extirpated. Although Giant native cane is still widespread, the 10-15 meter high impenetrable thickets (brakes) that once measured kilometers across are gone. Canebrakes existed along the Red River in the early 19th century and were frequently mentioned in the Red River Expedition accounts. Speaking of the river floodplain, Freeman said “the undergrowth is almost universally of cane, so strong, as seldom to allow the party to penetrate far from the margin of the river.” Sibley in 1805 reported canebrakes as being common north of the Great Raft of the Red River. They were common in eastern Texas as well. Exactly why they vanished remains a puzzle, but they seem to have been fragile, and settlers may have not only overgrazed them but probably also plowed them out of existence.
Brantley, C.G. and S. Platt. 2004. America’s canebrakes: an ecosystem management challenge. Pp. 109-113. Proc. of the Third Eastern Native Grass Symposium. North Carolina Botanical Garden, Chapel Hill.
Platt, S. and C.G. Brantley. 1997. Canebrakes: an ecological and historical perspective. Castanea 62:8-21.
Cedar Forest is mentioned many times in the Freeman and Custis account of the Red River in 1806. “Red cedar ... becomes more abundant as you ascend above the Coashatta village. In many places this is the principal tree found on the borders of the River.” Apparently, north of Shreveport, Louisiana, this species grew as a forest on both sides of the river for a distance of many miles. In 1977, Dan Flores searched the Red River for this species but did not see a single mature tree. Cedars were cut out by pioneer mill operators by the 1870s and apparently have not regenerated (cedar does not stump sprout). What unique plants this forest may have harbored may never be known. Early explorers provided no information about this community.
MacRoberts, D.T., B.R. MacRoberts, and M.H. MacRoberts. 1997. A floristic and ecological interpretation of the Freeman and Custis Red River expedition of 1806. Bull. Mus. Life Sci. 12:1-26.
Weches Glade are marine glauconite clay and marl outcrops, formed during the Eocene, and occur in a very limited area of Sabine, San Augustine, and Nacogdoches counties in Texas. They support a unique herbaceous flora in an area where forest is the general climax vegetation. Soils are shallow and basic and generally waterlogged in the spring. Texas golden gladecress and white bladderpod are endemic to these outcrops. This rare habitat has been vitually extirpated by land conversion to grazing and the mining of glauconite.
George, R.J. 1987. The herbaceous flora of three Weches outcrops in eastern Texas. M.S. thesis, Stephen F. Austin State University, Nacogdoches.
George, R.J. and E.S. Nixon. 1990. The herbaceous flora of three weches formation outcrops in eastern Texas. Sida 14:117-127.
Flatwoods Ponds are small, shallow wetlands of fewer than one to twenty hectares. They occur in longleaf pine savannas where they occupy swales or slight depressions with seasonally fluctuating water levels. They are generally treeless and dominated by tall sedges and grasses and wetland loving herbs such as pipewort, camphor weed, bedstraw St John’s wort, cluster bushmint, yellow rhexia, and arrowhead, species that may also occur in surrounding wetland pine savanna. Trees and shrubs --- red maple, hawthorn, wax myrtle and tupelo --- when present, are often stunted. These ponds often dry out in late summer, especially in droughty years.
Bridges, E.L. and S.L. Orzell. 1989. Longleaf pine communities of the West Gulf Coastal Plain. Natural Areas J. 9:246-363.
Sources describing many communities, with extensive bibliographies
Bridges, E.L. and S.L. Orzell. 1989. Longleaf pine communities of the West Gulf Coastal Plain. Natural Areas J. 9:246-363.
Diggs, G.M., B.L. Lipscomb, M.D. Reed, and R.J. O’Kennon. 2006. Illustrated flora of east Texas. Sida Bot. Misc. 26:1-1594.
Harcombe, P.A., J.S. Glitzenstein, R.G. Knox, S.L. Orzell, and E.L. Bridges. 1993. Vegetation of the longleaf pine region of the West Gulf Coastal Plain. Proceedings of the Tall Timbers Fire Ecology Conference 18:83-104.
Lester, G.D., S.G. Sorensen, P.L. Faulkner, C.S. Reid, and I.E. Maxit. 2005. Louisiana comprehensive wildlife conservation strategy. Louisiana Natural Heritage Program. Louisiana Department of Wildlife and Fisheries. Baton Rouge, Louisiana.
Marks, P.L. and P.A. Harcombe. 1981. Forest vegetation of the Big Thicket, southeast Texas. Ecology 56:1004-1008.
Mundorff, K.T. 1998. Ecological classification of bottomland hardwood forests in east Texas and central Louisiana. M.S. Thesis, Stephen F. Austin State University, Nacogdoches, Texas. 106 pp.
Van Kley, J.E. 2006. The pineywoods. Pp. 76-106. In: G.M. Diggs, B.L. Lipscomb, M.D.Reed, and R.J. O’Kennon, eds., Illustrated flora of east Texas. Sida Bot. Misc. 26:1-1594.
Van Kley, J.E., R.L. Turner, L.S. Smith, and R.E. Evans. 2007. Ecological classification system for the national forests and adjacent areas of the West Gulf Coastal Plain: 2nd approximation. The Nature Conservancy and Stephen F. Austin State University, Nacogdoches, Texas. 379 pp.
