Common (Translated Scientific) Name: Saltmeadow Cordgrass - Common Threesquare - Eastern Marsh Fern - Erect Centella Marsh
Colloquial Name: Mid-Atlantic Mixed Grassland Interdunal Swale
Hierarchy Level: Association
Type Concept: This interdunal wetland association has been documented from far southeastern Virginia. It occurs in seasonally flooded interdunal swales that experience longer hydroperiods than do other interdunal swale associations on the mid-Atlantic. It is characterized by relatively high species diversity, and is dominated by Centella erecta, Spartina patens, and/or Schoenoplectus pungens. Thelypteris palustris is characteristic. Other associates may include Osmunda regalis var. spectabilis, Polygonum punctatum, Proserpinaca palustris, and others.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features:
Classification Comments: The classification is based on analysis of a 211-plot dataset covering varied beach and dune vegetation across the Virginia coast. This association is supported by 15 plot samples and needs critical comparison with data from similar habitats in North Carolina. This group is equivalent to an aggregation of the Scirpus - Hydrocotyle and Spartina - Scirpus communities described from the Back Bay - False Cape area by Tyndall and Levy (1978).
Similar NVC Types:
(Morella cerifera) / Panicum virgatum - Spartina patens Wet Meadow, note:
Muhlenbergia filipes - Spartina patens - Rhynchospora colorata Marsh, note:
Schoenoplectus pungens - Fimbristylis (castanea, caroliniana) Marsh, note:
Physiognomy and Structure: No Data Available
Floristics: This vegetation is dense and stratified, dominated by tall graminoids such as Schoenoplectus pungens, Spartina patens, Saccharum giganteum, Panicum virgatum var. virgatum, and Eleocharis quadrangulata occurring over dense ground cover of Centella erecta and often Hydrocotyle umbellata. Thelypteris palustris var. pubescens and Osmunda regalis var. spectabilis may also be patch-dominant in places. Associated species may include Polygonum punctatum, Proserpinaca palustris, Juncus canadensis, Diodia virginiana, Eupatorium capillifolium, Dichanthelium scoparium, and Panicum verrucosum. Many other herbaceous species occur at low constancy and cover. Patches of Toxicodendron radicans, as well as seedlings or saplings of Diospyros virginiana, Pinus taeda, Salix caroliniana, Populus heterophylla, and Morella cerifera may be present.
Dynamics: The swale habitats occupied by this community are vulnerable to damage by foraging feral pigs, which have been established in the False Cape area for many decades.
Environmental Description: This association occurs in seasonally flooded interdunal depressions of large dune systems in the Back Bay - False Cape region of southeastern Virginia. These habitats vary in size from quite small to several acres in size. They are flooded to depths of approximately 25 cm or more in the winter and spring, but gradually draw down and are usually dry by late summer, except in unusually wet years.
Geographic Range: This association is documented from far southeastern Virginia and may also occur in North Carolina.
States/Provinces: NC?, VA
|US Forest Service Ecoregions (1994/1995)|
Outer Coastal Plain Mixed Forest Province
Confident or certain
Atlantic Coastal Flatwoods Section
Confident or certain
Confidence Level: Low - Poorly Documented
Confidence Level Comments:
Greasons: All natural interdunal wetlands on the U.S. Atlantic coast are rare and threatened. This community type is confined to seasonally flooded interdune swales in the Back Bay - False Cape region of Virginia Beach City, where it has been documented from one large occurrence of approximately 25 ha (60 acres) in 57 patches. Within the maritime dune systems of that region, it is restricted to the larger, wetter swales. Most occurrences have been damaged to some extent by feral hogs, and are susceptible to widespread compositional changes resulting from the intrusion of saltwater storm surges or from anthropogenic hydrological alterations.
Synonomy: ? Scirpus - Hydrocotyle community (Tyndall and Levy 1978)
? Spartina - Scirpus community (Tyndall and Levy 1978)
Concept Author(s): G.P. Fleming
Author of Description: L.A. Sneddon and G.P. Fleming
Version Date: 15Oct2014
- Eastern Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boston, MA.
- Fleming, G. P., and K. D. Patterson. 2011a. Natural communities of Virginia: Ecological groups and community types. Natural Heritage Technical Report 11-07. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. 34 pp.
- Tyndall, R. W., and G. F. Levy. 1978. Plant distribution and succession within interdunal depressions on a Virginia barrier dune system. Journal of the Elisha Mitchell Scientific Society 94:1-15.