Spotted Pondweed

Potamogeton pulcher Tuckerman

Potamogeton pulcher
Troy Weldy

Class
Monocotyledoneae (Monocots)
Family
Potamogetonaceae (Pondweed Family)
State Protection
Threatened
Listed as Threatened by New York State: likely to become Endangered in the foreseeable future. For animals, taking, importation, transportation, or possession is prohibited, except under license or permit. For plants, removal or damage without the consent of the landowner is prohibited.
Federal Protection
Not Listed
State Conservation Status Rank
S2
Imperiled in New York - Very vulnerable to disappearing from New York due to rarity or other factors; typically 6 to 20 populations or locations in New York, very few individuals, very restricted range, few remaining acres (or miles of stream), and/or steep declines.
Global Conservation Status Rank
G5
Secure globally - Common in the world; widespread and abundant (but may be rare in some parts of its range).

Summary

Did you know?

There are seven historical records from Long Island for this pondweed but it has not been documented there since 1952 when it was collected at Riverhead. There are a number of known locations in the Hudson Highlands though. The specific name means handsome since it is more colorful than most pondweeds.

State Ranking Justification

There are approximately ten known populations and nearly 25 historical locations for the aquatic plant. As an aquatic plant, it may be subject to changes in water chemistry, aquatic herbicides, intensive recreational boating, and invasive species. Long Island has experienced a substational decline of this plant. More populations might be found, but there also a few populations with low predicted viability.

Short-term Trends

Very few follow-up surveys have been done of these populations so short-term trends are unknown.

Long-term Trends

While new populations have been found in Hudson Highlands there has been a substantial decline on Long Island.

Conservation and Management

Threats

Most of the populations are buffered from development but there is a chance that aquatic invasive plants could threaten plant numbers.

Conservation Strategies and Management Practices

Monitor the growth and control of aquatic invasive plants.

Research Needs

Research into the physical parameters of this plant's water bodies would help to locate more populations.

Habitat

Habitat

A aquatic plant in the still or slowly moving water (1-2+ meters deep) of deep emergent marshes, small streams, small lakes/ponds, and open pools (New York Natural Heritage Program 2004). Shallow water (Gleason & Cronquist 1991).

Associated Ecological Communities

  • Bog lake/pond* (guide)
    the aquatic community of a dystrophic lake that typically occurs in a small, shallow basin (e.g., a kettehole) that is protected from wind and is poorly drained. These lakes occur in areas with non-calcareous bedrock or glacial till; many are fringed or surrounded by a floating mat of vegetation (in New York usually either bog or poor fen).
  • Deep emergent marsh (guide)
    A marsh community flooded by waters that are not subject to violent wave action. Water depths can range from 6 in to 6.6 ft (15 cm to 2 m). Water levels may fluctuate seasonally, but the substrate is rarely dry, and there is usually standing water in the fall.
  • Eutrophic dimictic lake* (guide)
    The aquatic community of a nutrient-rich lake that occurs in a broad, shallow basin. These lakes are dimictic: they have two periods of mixing or turnover (spring and fall); they are thermally stratified in the summer, and they freeze over and become inversely stratified in the winter.
  • Eutrophic pond* (guide)
    The aquatic community of a small, shallow, nutrient-rich pond. The water is usually green with algae, and the bottom is mucky. Eutrophic ponds are too shallow to remain stratified throughout the summer; they are winter-stratified, monomictic ponds.
  • Marsh headwater stream (guide)
    The aquatic community of a small, marshy perennial brook with a very low gradient, slow flow rate, and cool to warm water that flows through a marsh, fen, or swamp where a stream system originates. These streams usually have clearly distinguished meanders (i.e., high sinuosity) and are in unconfined landscapes.
  • Mesotrophic dimictic lake* (guide)
    The aquatic community of a lake that is intermediate between an oligotrophic lake and a eutrophic lake. These lakes are dimictic: they have two periods of mixing or turnover (spring and fall); they are thermally stratified in the summer, and they freeze over and become inversely stratified in the winter.
  • Oligotrophic dimictic lake* (guide)
    The aquatic community of a nutrient-poor lake that typically occurs in a deep, steeply-banked basin. These lakes are dimictic: they have two periods of mixing or turnover (spring and fall), they are thermally stratified in the summer, and they freeze over and become inversely stratified in the winter.
  • Oligotrophic pond* (guide)
    The aquatic community of a small, shallow, nutrient-poor pond. The water is very clear, and the bottom is usually sandy or rocky.
  • Reservoir/artificial impoundment
    The aquatic community of an artificial lake created by the impoundment of a river with a dam. Reservoirs are constructed to collect water for municipal and/or agricultural water use, to provide hydroelectric power, and to improve opportunities for recreational activities (e.g., boating, swimming), and development.
  • Winter-stratified monomictic lake* (guide)
    The aquatic community of a large, shallow lake that has only one period of mixing each year because it is very shallow in relation to its size, and is completely exposed to winds. These lakes typically never become thermally stratified in the summer, and are only stratified in the winter when they freeze over, and become inversely stratified (coldest water at the surface). They are eutrophic to mesotrophic.

* probable association but not confirmed.

Associated Species

  • Brasenia schreberi (water-shield)
  • Ceratophyllum demersum (common coon-tail)
  • Ceratophyllum echinatum (spiny-fruited coon-tail)
  • Decodon verticillatus (water-willow)
  • Elodea nuttallii (Nuttall's waterweed)
  • Megalodonta beckii
  • Najas flexilis (common water-nymph, common naiad)
  • Najas minor (eutrophic water-nymph, eutrophic naiad)
  • Nuphar variegata (common yellow pond-lily, common spatter-dock)
  • Nymphaea odorata
  • Pontederia cordata (pickerelweed)
  • Potamogeton amplifolius (big-leaved pondweed)
  • Potamogeton epihydrus (ribbon-leaved pondweed)
  • Sagittaria latifolia (common arrowhead)
  • Sparganium androcladum (large-fruited bur-reed)

Range

New York State Distribution

An aquatic plant from the Hudson Valley, Long Island, and Oswego County. Most known populations today are located within the Hudson Highlands. New York is near the northern edge of its range.

Global Distribution

An aquatic plant found chiefly along the coastal plain from southern Maine to Florida and Alabama. It is also known inland around southern Indiana to Missouri and Arkansas.

Identification Comments

General Description

This is an aquatic plant of acidic waters with oval to heart-shaped, long-stalked, floating leaves on stems that are dark-purple spotted. It also has submerged, lance-shaped leaves that have 19-35 veins and are translucent with crinkled edges.

Identifying Characteristics

An aquatic plant with stems and petioles that are usually dark spotted. The median and upper submersed leaves are translucent, lanceolate to lance-linear, and not arcuate or cordate, These leaves can taper to a short petiole or be nearly sessile. They are 0.8-1.8 dm long and 1-3.5 cm broad. The floating leaves are ovate to roundish and cordate or broadly rounded at base. These floating leaves have 19- 35 nerves that are essentially uniform. The fruits are rounded or lobed at base with the fruit body 3-4 mm long and 2.6-3.4 mm broad. This species is most easily distinguished by the broad submersed leaves, cordate floating leaves, and dark spotted stems.

Best Life Stage for Proper Identification

Only vegetative plants with stems and leaves are necessary for proper identification.

Similar Species

Potamogeton amplifolius does not have a black spotted stem.

Best Time to See

Vegetative plants emerge by mid-May and flowers have formed by mid-June. The plants can be found throughout the summer and into the early fall season. Since it can be identified vegetatively, surveys may be conducted anytime between mid-May and mid-October.

  • Vegetative
  • Fruiting

The time of year you would expect to find Spotted Pondweed vegetative and fruiting in New York.

Spotted Pondweed Images

Taxonomy

Spotted Pondweed
Potamogeton pulcher Tuckerman

  • Kingdom Plantae
    • Phylum Anthophyta
      • Class Monocotyledoneae (Monocots)
        • Order Najadales
          • Family Potamogetonaceae (Pondweed Family)

Additional Common Names

  • Pondweed

Additional Resources

Best Identification Reference

Crow, Garrett E. and C. Barre Hellquist. 2000. Aquatic and Wetland Plants of Northeastern North America: A revised and enlarged edition of Norman C. Fassett's a Manual of Aquatic Plants. Volume One: Pteridophytes, Gymnosperms, and Angiosperms: Dicotyledons. The University of Wisconsin Press. Madison, Wisconsin. 536 Pages.

Other References

Fernald, M.L. 1950. Gray's manual of botany. 8th edition. D. Van Nostrand, New York. 1632 pp.

Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp.

Hellquist, C.B. and G.E. Crow 1980. Aquatic Vascular Plants of New England: Part 1. Zosteraceae, Potamogetonaceae, Zannichelliaceae, Najadaceae. New Hampshire Agricultural Experiment Station University of New Hampshire. Station Bull. 515.

Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York.

Mitchell, Richard S. and Gordon C. Tucker. 1997. Revised Checklist of New York State Plants. Contributions to a Flora of New York State. Checklist IV. Bulletin No. 490. New York State Museum. Albany, NY. 400 pp.

New York Natural Heritage Program. 2010. Biotics database. New York Natural Heritage Program. New York State Department of Environmental Conservation. Albany, NY.

New York Natural Heritage Program. 2024. New York Natural Heritage Program Databases. Albany, NY.

Reschke, Carol. 1990. Ecological communities of New York State. New York Natural Heritage Program, New York State Department of Environmental Conservation. Latham, NY. 96 pp. plus xi.

Weldy, T. and D. Werier. 2010. New York flora atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research http://www.fccdr.usf.edu/. University of South Florida http://www.usf.edu/]. New York Flora Association http://newyork.plantatlas.usf.edu/, Albany, New York

Links

About This Guide

Information for this guide was last updated on: June 22, 2005

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Potamogeton pulcher. Available from: https://guides.nynhp.org/spotted-pondweed/. Accessed March 28, 2024.