Invalid Unit Specified
D049 Potamogeton spp. - Nuphar spp. - Myriophyllum spp. North American Freshwater Aquatic Vegetation Division

The U.S. National
Vegetation Classification
Type Concept Sentence: Floating-leaved and submergent aquatic vegetation found in permanently flooded but shallow freshwater sites across North America.
Collapse All::Expand All
Common (Translated Scientific) Name: Pondweed species - Pond-lily species - Water-milfoil species North American Freshwater Aquatic Vegetation Division
Colloquial Name: North American Freshwater Aquatic Vegetation
Hierarchy Level: Division
Type Concept: This division comprises floating-leaved and submergent freshwater herbaceous vegetation found across North America from northern Canada to northern Mexico. Dominant plants are floating-leaved and submergent herbaceous species. Total aquatic vegetation cover can range from moderate to complete. Emergent plants are scattered to absent, with emergent cover <10%. Cosmopolitan species are often dominant in this division, though regional variants occur. Dominant floating-leaved species include Azolla filiculoides, Brasenia schreberi, Nuphar spp., Polygonum amphibium, Potamogeton spp., Ranunculus aquatilis, Ranunculus trichophyllus, Wolffia spp., and Zannichellia palustris. Submerged vegetation such as Ceratophyllum spp., Elodea nuttallii, Elodea canadensis, and Myriophyllum spp. are also common. Non-rooted floating-leaved plants, particularly Lemna spp. and Spirodela polyrrhiza, can be common though their dynamic nature means they may move depending on wind and currents. The division crosses temperate, boreal, and cool semi-desert climates across North America from northern Canada to northern Mexico. Freezing temperatures occur throughout these regions. Hydrologic conditions are relatively stable at these sites with permanent flooding in the growing season and water that moves at moderate speeds or less, except possibly during flood events. Thus, most stands in this division are in the shallower portions of ponds, lakes, and slow-moving edges or backwaters of permanent rivers and streams. Average water depth is often 1 m or more since shallower water is usually dominated by emergent species. The maximum depth in which this division can occur varies with water clarity but it can often be in water 1-3 m deep. Water chemistry is fresh to mildly saline.
Diagnostic Characteristics: Diagnostic criteria include permanently flooded freshwater wetlands with sparse to absent emergent plants and dominated by floating-leaved or submergent herbaceous plants. Dominant floating-leaved species include Azolla filiculoides, Brasenia schreberi, Nuphar spp., Polygonum amphibium, Potamogeton spp., Ranunculus aquatilis, Ranunculus trichophyllus, Wolffia spp., and Zannichellia palustris. Submerged vegetation such as Ceratophyllum spp., Elodea nuttallii, Elodea canadensis, and Myriophyllum spp. are also common. Non-rooted floating-leaved plants include Lemna spp. and Spirodela polyrrhiza.
Rationale for Nominal Species or Physiognomic Features:
Classification Comments: Stands of this division occur between shallow, emergent marshes or the upland boundary of a wetland and deeper water that does not support rooted vegetation. Stands of this division (D049) often occur adjacent to emergent marshes (2.C.4.Ne Atlantic & Gulf Coastal Marsh, Wet Meadow & Shrubland Division (D322), 2.C.4.Nd Eastern North American Temperate & Boreal Freshwater Marsh, Wet Meadow & Shrubland Division (D323), 2.C.4.Nb Western North American Temperate & Boreal Freshwater Marsh, Wet Meadow & Shrubland Division (D031), or 2.C.4.NcSouthwestern North American Warm Desert Freshwater Marsh & Bosque Division (D032)), but differences in physiognomy and floristics make differentiation relatively easy.
Similar NVC Types:
D097 Neotropical Freshwater Aquatic Vegetation, note: occurs further south.
D065 Temperate Estuarine & Inland Brackish Aquatic Vegetation, note:
D322 Atlantic & Gulf Coastal Marsh, Wet Meadow & Shrubland, note:
Physiognomy and Structure: Dominant plants are floating-leaved and submergent herbaceous species. Total aquatic vegetation cover can range from sparse to dense. Emergent plants are scattered to absent, with <10% cover.
Floristics: Cosmopolitan species are often dominant in this division, though regional variants occur. Dominant floating-leaved species include Azolla filiculoides, Brasenia schreberi, Nuphar spp., Polygonum amphibium, Potamogeton spp., Ranunculus aquatilis, Ranunculus trichophyllus, Wolffia spp., and Zannichellia palustris. Submerged vegetation such as Ceratophyllum spp., Elodea nuttallii, Elodea canadensis, and Myriophyllum spp. are also common. Non-rooted floating-leaved plants, particularly Lemna spp. and Spirodela polyrrhiza, can be common, though their dynamic nature means they may move depending on wind and currents.
Dynamics: Non-rooted floating-leaved plants may move over waterbodies depending on wind and currents. Where water levels fluctuate, or decline due to hydrological changes to a waterbody, emergent vegetation may establish, and this type may succeed to emergent wetland types.
Environmental Description: Climate: The division crosses temperate, boreal, and cool semi-desert climates across North America from northern Canada to northern Mexico. Freezing temperatures occur throughout these regions.

Soils/substrate: Hydrologic conditions are relatively stable at these sites with permanent flooding in the growing season and water that moves at moderate speeds or less, except possibly during flood events. Thus, most stands in this division are in the shallower portions of ponds, lakes, and slow-moving edges or backwaters of permanent rivers and streams. Average water depth is often 1 m or more since shallower water is usually dominated by emergent species. The maximum depth in which this division can occur varies with water clarity but it can often be in water 1-3 m deep. Water chemistry is fresh to mildly saline.

Biogeography: This division extends across all of temperate, boreal and cool semi-desert regions of North America, driven largely by the presence of available permanent waterbodies that are deep enough to exclude emergent vegetation.
Geographic Range: This division occurs throughout North America from northern Canada to northern Mexico and from coastal areas (though not ocean-influenced waters) to montane sites.
Nations: CA, MX, US
States/Provinces: AB, AK, AL, AR, BC, CA, CO, CT, DE, FL, GA, IA, ID, IL, IN, KS, KY, LA, MA, MB, MD, ME, MI, MN, MO, MS, MT, NB, NC, ND, NE, NF, NH, NJ, NM, NS, NV, NY, OH, OK, ON, OR, PA, PE, QC, RI, SC, SD, SK, TN, TX, VA, VT, WA, WI, WV, WY
US Forest Service Ecoregions (2007)
Domain Name:
Division Name:
Province Name: Southwest Plateau and Plains Dry Steppe and Shrub Province
Province Code: 315    Occurrence Status: Confident or certain
Section Name:
Section Code:     Occurrence Status: Confident or certain
Omernik Ecoregions:
Plot Analysis Summary:
Confidence Level: Moderate
Confidence Level Comments:
Grank: GNR
Greasons:
Concept Lineage:
Predecessors:
Obsolete Names:
Obsolete Parents:
Synonomy: > Lacustrine, Aquatic Beds, Rooted Vascular (Cowardin et al. 1979)
> Palustrine, Aquatic Beds, Rooted Vascular (Cowardin et al. 1979)
> Riverine, Aquatic Beds, Rooted Vascular (Cowardin et al. 1979)
Concept Author(s): W.J. Mitsch and J.G. Gosselink (2000)
Author of Description: J. Drake and D. Faber-Langendoen
Acknowledgements:
Version Date: 06Jan2016
References:
  • Barbour, M. G., and W. D. Billings, editors. 2000. North American terrestrial vegetation. Second edition. Cambridge University Press, New York. 434 pp.
  • Cowardin, L. M., V. Carter, F. C. Golet, and E. T. LaRoe. 1979. Classification of wetlands and deepwater habitats of the United States. FWS/OBS-79/31. USDI Fish & Wildlife Service, Office of Biological Services, Washington, DC. 103 pp.
  • 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. 2010-2019a. Divisions, Macrogroups and Groups for the Revised U.S. National Vegetation Classification. NatureServe, Arlington, VA. plus appendices. [in preparation]
  • Mitsch, W. J., and J. G. Gosselink. 2000. Wetlands. Third edition. John Wiley & Sons, Inc., New York. 920 pp.