Invalid Unit Specified
D062 Taxodium distichum - Nyssa biflora - Quercus lyrata Flooded & Swamp Forest Division

The U.S. National
Vegetation Classification
Type Concept Sentence: These wetland forests occur in a variety of wetland settings, such as floodplain / riparian, isolated basins, and seepage slopes, centered in the Southeastern Coastal Plain of the United States.
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Common (Translated Scientific) Name: Bald-cypress - Swamp Tupelo - Overcup Oak Flooded & Swamp Forest Division
Colloquial Name: Southeastern North American Flooded & Swamp Forest
Hierarchy Level: Division
Type Concept: The bulk of this division includes wetland forests typically dominated by wetland Quercus spp., Taxodium spp., and Nyssa spp., often with a diverse admixture of other tree species, including Carya spp., Celtis spp., Acer spp., Fraxinus spp., Gleditsia spp., Populus spp., Salix spp., Liquidambar styraciflua, Liriodendron tulipifera, Juglans nigra, Platanus occidentalis, Planera aquatica, Ulmus spp., and others. Particularly southwards, evergreen conifers and broadleaf species may also be codominant, dominant, or at least present, including Pinus spp., Chamaecyparis thyoides, Magnolia spp., Persea palustris, Cyrilla racemiflora, Cliftonia monophylla, etc. The hydrology of sites varies from temporarily flooded, through seasonally flooded (often of weeks to months), to semipermanently flooded regimes (where there is surficial water for much of the growing season). The canopy is closed (a forest) in most of the communities, but can be a more open woodland, especially in basin swamps and in more deeply flooded communities in the division, in which recruitment is impeded by the frequency and depth of flooding. Many of the characteristic species are endemic to the region, and endemic or nearly so to this division. Characteristic species include Acer negundo, Acer rubrum, Acer saccharinum, Carya aquatica, Carya illinoinensis, Celtis laevigata, Chamaecyparis thyoides, Fraxinus caroliniana (= Fraxinus cubensis), Fraxinus pennsylvanica, Fraxinus profunda, Gleditsia aquatica, Gleditsia triacanthos, Juglans nigra, Liriodendron tulipifera, Magnolia grandiflora, Magnolia virginiana, Nyssa aquatica, Nyssa biflora, Nyssa ogeche, Nyssa ursina, Persea palustris, Pinus elliottii var. elliottii, Pinus glabra, Pinus serotina, Pinus taeda, Planera aquatica, Platanus occidentalis, Populus heterophylla, Quercus laurifolia, Quercus lyrata, Quercus michauxii, Quercus phellos, Quercus similis, Salix caroliniana, Salix nigra, Taxodium ascendens, Taxodium distichum, Ulmus americana, Ulmus crassifolia, and others. Lianas are often frequent and diverse, including Ampelopsis arborea, Berchemia scandens, Bignonia capreolata, Campsis radicans, Decumaria barbara, Gelsemium rankinii, Gelsemium sempervirens, Parthenocissus quinquefolia, and Vitis spp.; these show a strong tropical affinity with such families as Bignoniaceae, Gelsemiaceae, Vitaceae, and Rhamnaceae. Epiphytic orchids and bromeliads are characteristic and sometimes abundant and diverse in the more southern part of the division's range, but extend in an attenuated and depauperate manner north to southeastern Virginia. Herbaceous layers are sometimes suppressed by flood regimes and dense shade, but some communities in this division are diverse, especially in fire-affected basin swamps with more open canopies and shallow, seasonal flooding. Floristically, this division shows a strong signal of Southeastern North American endemic species and genera, disjunct southeastern Asian / eastern North American elements, widespread temperate elements (variously of North America or broadly northern hemisphere), and with a substantial admixture of neotropical components.

This division is found in the Coastal Plain, which extends from the fall-line to the edge of the continental shelf, and consists of alluvial and marine sediments. Much of the sediment, particularly at the surface, is siliceous alluvium, along with carbonaceous sediment. Common soil orders include sandy Entisols, Inceptisols, and Ultisols. The near-coastal maritime examples are affected by coastal processes, and are prone to salt spray effects and storm surge from major hurricanes. The climate of the coastal plain is humid subtropical, also referred to as warm-temperate, with mean daily temperatures between 0 and 18°C in the coldest month and >22°C in the warmest month. Rainfall is distributed evenly throughout the year, and averages about 100 to 135 cm (40-55 cm a year). This region has the highest frequency of lightning strikes of any region in North America, leading to frequent fires, but unlike in the uplands, fires affect only some of the basin swamp communities in this division.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features:
Classification Comments: No Data Available
Similar NVC Types:
D011 Eastern North American-Great Plains Flooded & Swamp Forest, note:
D324 Atlantic & Gulf Coastal Plain Pocosin, note:
Physiognomy and Structure: The canopy is closed (a forest) in most of the communities, but can be a more open woodland, especially in basin swamps dominated by Taxodium ascendens, and in more deeply flooded communities in the division, in which recruitment is impeded by the frequency and depth of flooding. Herbaceous layers are sometimes suppressed by flood regimes and dense shade, but some communities in this division are diverse, especially in fire-affected basin swamps with more open canopies and shallow, seasonal flooding.
Floristics: Characteristic species include Acer negundo, Acer rubrum, Acer saccharinum, Carya aquatica, Carya illinoinensis, Celtis laevigata, Chamaecyparis thyoides, Fraxinus caroliniana (= Fraxinus cubensis), Fraxinus pennsylvanica, Fraxinus profunda, Gleditsia aquatica, Gleditsia triacanthos, Juglans nigra, Liriodendron tulipifera, Magnolia grandiflora, Magnolia virginiana, Nyssa aquatica, Nyssa biflora, Nyssa ogeche, Nyssa ursina, Persea palustris, Pinus elliottii var. elliottii, Pinus glabra, Pinus serotina, Pinus taeda, Planera aquatica, Platanus occidentalis, Populus heterophylla, Quercus laurifolia, Quercus lyrata, Quercus michauxii, Quercus phellos, Quercus similis, Salix caroliniana, Salix nigra, Taxodium ascendens, Taxodium distichum, Ulmus americana, Ulmus crassifolia, and others. Lianas are often frequent and diverse, including Ampelopsis arborea, Berchemia scandens, Bignonia capreolata, Campsis radicans, Decumaria barbara, Gelsemium rankinii, Gelsemium sempervirens, Parthenocissus quinquefolia, and Vitis spp.; these show a strong tropical affinity with such families as Bignoniaceae, Gelsemiaceae, Vitaceae, and Rhamnaceae. Epiphytic orchids and bromeliads are characteristic and sometimes abundant and diverse in the more southern part of the division's range, but extend in an attenuated and depauperate manner north to southeastern Virginia.
Dynamics: The communities in this division are generally relatively stable in composition and structure. Like all communities in the southeastern United States they are subject to rare catastrophic disturbances such as blowdown from hurricanes or tornados, or extraordinary flood events from hurricanes, northeasters, or frontal events, but they are generally resilient to anything less than truly extraordinary flooding events. Communities in basin swamps located in upland matrix communities (such as longleaf pine-dominated communities) experience low to moderate intensity (but not stand-replacing) fires on an irregular basis, when matrix fires occur in seasons or during years when the community is dry enough to carry fire.
Environmental Description: Climate: The climate of the Coastal Plain is humid subtropical, also referred to as warm-temperate, with mean daily temperatures between 0 and 18°C in the coldest month and >22°C in the warmest month. Rainfall is distributed evenly throughout the year, and averages about 100 to 135 cm (40-55 cm a year). This region has the highest frequency of lightning strikes of any region in North America, leading to frequent fires, but unlike in the uplands, fires affect only some of the basin swamp communities in this division.

Soils/substrate: Soils are highly variable. Most soils are recent alluvium, but vary from fertile and nutrient-rich loams associated with brownwater rivers to high-organic, acidic, and nutrient-poor soils associated with blackwater streams and rivers. Some are also on coastal plain terraces of sands, silts, and clays, from Cretaceous to Holocene ages. The hydrology of sites varies from temporarily flooded (of infrequent occurrence and short duration), through seasonally flooded (of more seasonal occurrence, predominantly in the low evapotranspiration season of winter, and of longer duration, often of weeks to months), to semipermanently flooded regimes (where there is surficial water for much of the growing season).

Biogeography: Nearly all species in communities of this division are endemic to eastern North America, with many being more restricted endemics of the southeastern United States or the Southeastern Coastal Plain. At higher taxonomic levels (genus and family), the floristic affinities show a strong admixture of (1) Circumboreal temperate elements (Salix, Pinus, Populus, Quercus, etc.), relictual temperate elements often with an eastern North America / east Asian disjunct pattern (Carya, Juglans, Taxodium, Schisandraceae, etc.), neotropical elements (Bignoniaceae, Gelsemiaceae, Persea, Cyrillaceae, Magnolia subgenus Magnolia), and relictual tropical/subtropical elements (Illiciaceae).
Geographic Range: This division is found predominantly in the Southeast Coastal Plain of the United States, with some outlier examples in adjacent regions.
Nations: US
States/Provinces: AL, AR, CT, DC, DE, FL, GA, IL, IN, KY, LA, MA, MD, MO, MS, NC, NJ, NY, OK, PA, SC, TN, TX, VA, WV
US Forest Service Ecoregions (2007)
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Plot Analysis Summary:
Confidence Level: Moderate
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Grank: GNR
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Concept Author(s): Faber-Langendoen et al. (2016)
Author of Description: A.S. Weakley
Acknowledgements:
Version Date: 15Jan2016
References:
  • Faber-Langendoen, D., J. Drake, S. Gawler, M. Hall, C. Josse, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, L. Sneddon, K. Schulz, J. Teague, M. Russo, K. Snow, and P. Comer, editors. 2010-2017a. Divisions, Macrogroups and Groups for the Revised U.S. National Vegetation Classification. NatureServe, Arlington, VA. plus appendices. [in preparation]