Invalid Unit Specified
CEGL006481 Eupatorium serotinum - Polygonum (lapathifolium, punctatum, pensylvanicum) Riverbar Wet Meadow

The U.S. National
Vegetation Classification
Type Concept Sentence:
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Common (Translated Scientific) Name: Late-flowering Thoroughwort - (Curlytop Knotweed, Dotted Smartweed, Pennsylvania Smartweed) Riverbar Wet Meadow
Colloquial Name: Piedmont-Central Appalachian Scour Bar Wet Meadow
Hierarchy Level: Association
Type Concept: This association is known only from the Potomac River in the Piedmont and mountain provinces of Maryland, Virginia, and West Virginia. Well-documented occurrences are concentrated in high-gradient reaches of the Potomac, particularly near the fall-line (Potomac Gorge) and at Harpers Ferry. The type occurs on sandy riverbanks and depositional bars, as well as in sand deposits on bedrock floodplains and boulder bars. These habitats experience high rates of sediment erosion and turnover during even moderate floods and are inundated for 3-12% of the year, but are generally exposed for most of the growing season. Vegetation may be sparse during years of more continuous high water during the growing season. In normal growing seasons, the type is a dense growth of tall (1-2 m), predominantly annual herbs. Some weedy, fast-growing perennials are also characteristic. Artemisia annua, Amaranthus spinosus, Datura stramonium, Eupatorium serotinum, Polygonum lapathifolium, Polygonum pensylvanicum, Polygonum punctatum, and Verbena urticifolia are relatively constant and generally contribute most of the cover. Additional, less constant or abundant species include Chenopodium ambrosioides, Conoclinium coelestinum (= Eupatorium coelestinum), Hibiscus laevis, Mollugo verticillata, Perilla frutescens, Polygonum caespitosum var. longisetum, Solanum carolinense, Solanum ptychanthum, Teucrium canadense, Urtica dioica ssp. dioica, Verbena hastata, and Verbesina alternifolia. Herbaceous vines may also be numerous, with Calystegia sepium, Cynanchum laeve, and Cuscuta gronovii most frequent. Scattered individuals of shrubby to full-sized flood-tolerant trees (e.g., Platanus occidentalis, Acer saccharinum) may be present.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features:
Classification Comments: Classification is supported by analysis of data from 19 plots sampled throughout the known range. Currently, the type is classified as natural that, like most floodplain communities in the Mid-Atlantic region, has been altered to a considerable degree by post-settlement disturbances. However, approximately 30% of this community's characteristic species are weedy exotics, and further study is needed to determine whether this vegetation should be considered a natural or modified type.
Similar NVC Types:
Verbesina alternifolia - Elymus riparius - Solidago gigantea - (Teucrium canadense) Riverbar Wet Meadow, note: of more stable riverbanks and depositional bars with low sediment turnover during floods and prevalence of perennial herbs.
Physiognomy and Structure: No Data Available
Floristics: Vegetation may be sparse during years of more continuous high water during the growing season. In normal growing seasons, the type is a dense growth of tall (1-2 m) predominantly annual herbs. Some weedy, fast-growing perennials are also characteristic. These include Amaranthus spinosus, Artemisia annua, Datura stramonium, Eupatorium serotinum, Polygonum lapathifolium, Polygonum pensylvanicum, Polygonum punctatum, Teucrium canadense, Verbesina alternifolia, and Verbena urticifolia, which are relatively constant and generally contribute most of the cover. Additional, less constant or abundant species include Chenopodium ambrosioides, Conoclinium coelestinum (= Eupatorium coelestinum), Hibiscus laevis, Mollugo verticillata, Perilla frutescens, Polygonum caespitosum var. longisetum, Solanum carolinense, Solanum ptychanthum, Teucrium canadense, Urtica dioica ssp. dioica, Verbena hastata, and Verbesina alternifolia. Herbaceous vines may also be numerous, with Calystegia sepium, Cynanchum laeve, and Cuscuta gronovii most frequent. Scattered individuals of shrubby to full-sized flood-tolerant trees (e.g., Platanus occidentalis, Acer saccharinum) may be present.
Dynamics: In habitats occupied by this community, sediment deposition is apparently frequent enough and sediment turnover extensive enough during even relatively small floods that most established perennial species are quickly buried or scoured away. These conditions favor the prevalence of annual herbs and rapidly growing perennials, both of which probably produce extensive seedbanks. It is uncertain whether this association is fully natural, as approximately 30% of its characteristic species are not indigenous to the region. While it is likely that this vegetation has been altered in both composition and distribution by anthropogenic watershed changes increasing the frequency and level of floods on the Potomac (favoring annual species and exotics), it also seems reasonable to presume that some similar form of low, frequently flooded depositional bar originally occurred along higher gradient stretches of the very powerful Potomac River. For now, the type is classified as a natural type that, like most floodplain communities, has been altered to a considerable degree by post-settlement disturbances. Multi-year research would be needed to elucidate competitive dynamics of this community type and to fully evaluate its conservation value.
Environmental Description: The type occurs on sandy riverbanks and depositional bars, as well as in sand deposits on bedrock floodplains and boulder bars. These habitats experience high rates of sediment erosion and turnover during even moderate floods and are inundated for 3-12% of the year (Lea 2000), but are generally exposed for most of the growing season.
Geographic Range: This association is known only from the Potomac River in the Piedmont and mountain provinces of Maryland, Virginia, and West Virginia. Well-documented occurrences are concentrated in high-gradient reaches of this river, particularly near the fall-line (Potomac Gorge) and at Harpers Ferry.
Nations: US
States/Provinces: DC, MD, VA, WV
US Forest Service Ecoregions (1994/1995)
Domain Name:
Division Name:
Province Name: Central Appalachian Broadleaf Forest - Coniferous Forest - Meadow Province
Province Code: M221    Occurrence Status: Confident or certain
Section Name: Blue Ridge Mountains Section
Section Code: M221D     Occurrence Status: Confident or certain
Omernik Ecoregions:
Confidence Level: Moderate
Confidence Level Comments:
Grank: GNR
Greasons: More data on the global range and dynamics are needed to rank this community.
Concept Lineage:
Predecessors:
Obsolete Names:
Obsolete Parents:
Synonomy: = Datura stramonium - Eupatorium serotinum - Polygonum (punctatum, lapathifolium, pensylvanicum) Herbaceous Vegetation (Lea 2003)
= Eupatorium serotinum - Cynanchum laeve - Polygonum (pensylvanicum, punctatum, lapathifolium) Herbaceous Vegetation (Fleming and Patterson 2003)
= Eupatorium serotinum - Polygonum (lapathifolium, punctatum, pensylvanicum) Herbaceous Vegetation (Fleming and Taverna 2006)
= Eupatorium serotinum - Polygonum (lapathifolium, punctatum, pensylvanicum) Herbaceous Vegetation (Fleming 2007)
= Polygonum (punctatum, lapathifolium, pensylvanicum) - Verbena urticifolia / Ampelamus albidus Herbaceous Vegetation (Lea 2000)
Concept Author(s): C. Lea
Author of Description: C. Lea and G.P. Fleming
Acknowledgements:
Version Date: 01Jun2007
References:
  • Eastern Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boston, MA.
  • Fleming, G. P. 2007. Ecological communities of the Potomac Gorge in Virginia: Composition, floristics, and environmental dynamics. Natural Heritage Technical Report 07-12. Unpublished report submitted to the National Park Service. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. 341 pp. plus appendices.
  • Fleming, G. P., and K. D. Patterson. 2003. Preliminary vegetation classification for the National Capitol Region parks. Regional (VA-WVA-MD-DC) analysis prepared for NatureServe and USGS-NPS Vegetation Mapping Program, March 2003. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond.
  • 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.
  • Fleming, G. P., and K. Taverna. 2006. Vegetation classification for the National Capitol Region parks, western region. Regional (VA-WVA-MD-DC) analysis prepared for NatureServe and USGS-NPS Vegetation Mapping Program, March 2006. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond.
  • Fleming, G. P., P. P. Coulling, D. P. Walton, K. M. McCoy, and M. R. Parrish. 2001. The natural communities of Virginia: Classification of ecological community groups. First approximation. Natural Heritage Technical Report 01-1. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. 76 pp.
  • Fleming, G. P., P. P. Coulling, K. D. Patterson, and K. M. McCoy. 2004. The natural communities of Virginia: Classification of ecological community groups. Second approximation. Natural Heritage Technical Report 04-01. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. [http://www.dcr.virginia.gov/dnh/ncintro.htm]
  • Harrison, J. W. 2011. The natural communities of Maryland: 2011 working list of ecological community groups and community types. Unpublished report. Maryland Department of Natural Resources, Wildlife and Heritage Service, Natural Heritage Program, Annapolis. 33 pp.
  • Harrison, J. W., compiler. 2004. Classification of vegetation communities of Maryland: First iteration. A subset of the International Classification of Ecological Communities: Terrestrial Vegetation of the United States, NatureServe. Maryland Natural Heritage Program, Maryland Department of Natural Resources, Annapolis. 243 pp.
  • Lea, C. 2000. Plant communities of the Potomac Gorge and their relationship to fluvial factors. M.S. thesis, George Mason University. Fairfax, VA. 219 pp.
  • Lea, C. 2003. Vegetation types in the National Capital Region Parks. Draft for review by NatureServe, Virginia Natural Heritage, West Virginia Natural Heritage, Maryland Natural Heritage, and National Park Service. March 2003. 140 pp.
  • Lea, C. 2004. Draft vegetation types in National Capital Region Parks. Edited by S.C. Gawler and J. Teague. Working draft for review by NatureServe, Virginia Natural Heritage, West Virginia Natural Heritage, Maryland Natural Heritage, and National Park Service. July 2004. 157 pp.
  • Walton, D. P., P. P. Coulling, J. Weber, A. Belden, Jr., and A. C. Chazal. 2001. A plant community classification and natural heritage inventory of the Pamunkey River floodplain. Unpublished report submitted to the U.S. Environmental Protection Agency. Natural Heritage Technical Report 01-19. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. 200 pp. plus appendices.