Print Report

A3927 Potamogeton natans - Polygonum amphibium Aquatic Vegetation Alliance

Type Concept Sentence: This alliance is of aquatic floating vegetation dominated by any of the following species: Myriophyllum spicatum, Polygonum amphibium, Potamogeton diversifolius, Potamogeton foliosus, Potamogeton natans, Potamogeton richardsonii , or Stuckenia filiformis or a combination of these. Stands occur in permanent ponds throughout the western U.S. and western Canada.

Common (Translated Scientific) Name: Floating Pondweed - Water Knotweed Aquatic Vegetation Alliance

Colloquial Name: Western Floating Pondweed - Knotweed Aquatic Vegetation

Hierarchy Level:  Alliance

Type Concept: This alliance is of aquatic floating vegetation dominated by Myriophyllum spicatum, Polygonum amphibium, Potamogeton diversifolius, Potamogeton foliosus, Potamogeton natans, Potamogeton richardsonii , or Stuckenia filiformis or a combination of these. Associated species include Brasenia schreberi, Nuphar polysepala, Sagittaria cuneata, and Utricularia macrorhiza. They generally all occur in shallow ponds that are either bedrock or sand, filled by snowmelt or summer runoff. Elevation ranges from 100-2530 m (300-8300 feet). Ponds and other waterbodies are permanently wet; however, some may have water levels that vary greatly during the year.

Diagnostic Characteristics: Aquatic bed vegetation dominated by Myriophyllum spicatum, Polygonum amphibium, Potamogeton diversifolius, Potamogeton foliosus, Potamogeton natans, Potamogeton richardsonii, or Stuckenia filiformis or a combination of these.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Many of these aquatic alliances could be combined to account for the high degree of mixing possible with aquatic bed-dominated species.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: Aquatic floating broad-leaved forbs. The coverage over the water surface ranges from 10 to 60% cover.

Floristics: The herbaceous aquatic bed is dominated by Myriophyllum spicatum, Polygonum amphibium, Potamogeton diversifolius, Potamogeton foliosus, Potamogeton natans, Potamogeton richardsonii, or Stuckenia filiformis or a combination of these. Associated species include Brasenia schreberi, Nuphar polysepala (= Nuphar lutea ssp. polysepala), Sagittaria cuneata, and Utricularia macrorhiza. Communities may be monotypic or mixed (Lesica 1989, Sanderson and Kettler 1996).

Dynamics:  No Data Available
Environmental Description:  This alliance occurs in the permanently inundated, "deep water" zone of glacial ponds in gentle, rolling, glacial terrain. Water is usually 15 to >100 cm deep. Types typically occur in fresh to moderately brackish water (Lesica 1989). The water is generally still, though it may be moving very slowly through beaver ponds, and is typically nutrient-rich (Sanderson and Kettler 1996). The underlying parent material is mixed sedimentary (partly calcareous) glacial till. Pond bottoms are typically composed of mud, organic mud, or mud mixed with gravel and stones (Faber-Langendoen et al. 1997).
Geographic Range: This alliance is found in ponds and waterbodies throughout the temperate western U.S. and western Canada.

Nations: CA,US

States/Provinces:  BC, CA, CO, ID, MT, ND, OR, SD, SK?, UT, WA, WY


Confidence Level: Low

Confidence Level Comments: No Data Available
Grank: GNR

Greasons: No Data Available
Type Name Database Code Classification Code
Class 5 Aquatic Vegetation Class C05 5
Subclass 5.B Freshwater Aquatic Vegetation Subclass S13 5.B
Formation 5.B.2 Temperate to Polar Freshwater Aquatic Vegetation Formation F057 5.B.2
Division 5.B.2.Na North American Freshwater Aquatic Vegetation Division D049 5.B.2.Na
Macrogroup 5.B.2.Na.2 Rocky Mountain Pond-lily - Pacific Mosquito Fern - Western Waterweed Western North American Freshwater Aquatic Vegetation Macrogroup M109 5.B.2.Na.2
Group 5.B.2.Na.2.a Pond-lily species - Pondweed species - Duckweed species Freshwater Aquatic Vegetation Group G544 5.B.2.Na.2.a
Alliance A3927 Floating Pondweed - Water Knotweed Aquatic Vegetation Alliance A3927 5.B.2.Na.2.a
Association CEGL002002 Water Knotweed Aquatic Vegetation CEGL002002 5.B.2.Na.2.a
Association CEGL002006 Richardson''s Pondweed - Eurasian Water-milfoil Aquatic Vegetation CEGL002006 5.B.2.Na.2.a
Association CEGL002007 Waterthread Pondweed Aquatic Vegetation CEGL002007 5.B.2.Na.2.a
Association CEGL002742 Leafy Pondweed Aquatic Vegetation CEGL002742 5.B.2.Na.2.a
Association CEGL002925 Floating Pondweed Aquatic Vegetation CEGL002925 5.B.2.Na.2.a
Association CEGL003330 Marsh Seedbox - Swamp Smartweed Aquatic Vegetation CEGL003330 5.B.2.Na.2.a
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: ? Stuckenia (pectinata) - Potamogeton spp. (Pondweed mats) Alliance (Sawyer et al. 2009) [52.107.00]
? Open Water Phase of Slightly Brackish Ponds and Lakes (Stewart and Kantrud 1971)
? Pondweeds with Submerged Leaves Series (Sawyer and Keeler-Wolf 1995)
Concept Author(s): G. Kittel, in Faber-Langendoen et al. (2013)

Author of Description: G. Kittel

Acknowledgements: No Data Available

Version Date: 03-14-14
  • Faber-Langendoen, D., J. Drake, G. Jones, D. Lenz, P. Lesica, and S. Rolfsmeier. 1997. Rare plant communities of the northern Great Plains. Report to Nebraska National Forest, The Nature Conservancy. 155 pp.
  • Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
  • Hickman, J. C. 1993. The Jepson manual: Higher plants of California. University of California Press, Ltd., Berkeley, CA. 1400 pp.
  • Lesica, P. 1989. The vegetation and flora of glaciated prairie potholes of the Blackfeet Indian Reservation, Montana. Final report to The Nature Conservancy, Montana Field Office, Helena, MT. 26 pp.
  • Lesica, P. 1993. Using plant community diversity in reserve design for pothole prairie on the Blackfeet Indian Reservation, Montana, USA. Biological Conservation 65:69-75.
  • MTNHP [Montana Natural Heritage Program]. No date. Unpublished data on file. Montana Natural Heritage Program, Helena, MT.
  • Sanderson, J., and S. Kettler. 1996. A preliminary wetland vegetation classification for a portion of Colorado''s west slope. Report prepared for Colorado Department of Natural Resources, Denver, CO, and U.S. Environmental Protection Agency, Region VIII, Denver, CO. Colorado Natural Heritage Program, Fort Collins, CO. 243 pp.
  • Sawyer, J. O., T. Keeler-Wolf, and J. Evens. 2009. A manual of California vegetation. Second edition. California Native Plant Society, Sacramento CA. 1300 pp.
  • Sawyer, J. O., and T. Keeler-Wolf. 1995. A manual of California vegetation. California Native Plant Society, Sacramento. 471 pp.
  • Stewart, R. E., and H. A. Kantrud. 1971. Classification of natural ponds and lakes in the glaciated prairie region. USDI Bureau of Sport Fisheries and Wildlife Resources, Publication 92. Washington, DC. 77 pp.