Photo by Brenton Butterfield
- WDNR
State Rank: S4 Global Rank: G5 what are these ranks?
This herbaceous community of aquatic macrophytes occurs in lakes, ponds, and rivers. Submergent macrophytes often occur in deeper water than beds of floating-leaved or emergent species, but there is considerable overlap. Submergent marshes can also be found in deep water wetlands and flowages that have little moving water present. Water depth, water chemistry, water movement, and type of bottom material are among the key ecological factors that determine the nature of the submergent beds. The chemical nature of the water can greatly affect the types and abundance of aquatic plants present. Common or characteristic species and genera include various species of pondweeds (Potamogeton spp.), waterweed (Elodea spp.), coon-tail (Ceratophyllum spp.), slender naiad (Najas flexilis), eel-grass (Vallisneria americana), and several species of water-milfoil (Myriophyllum spp.) and bladderwort (Utricularia spp.).
Aquatic plants, including both emergent and submergent, form the foundation of healthy and flourishing aquatic ecosystems - both within lakes and rivers and on the shores and wetlands around them. They not only protect water quality, but they also produce life-giving oxygen. Aquatic plants are a lake's own filtering system, helping to clarify the water by absorbing nutrients like phosphorus and nitrogen that could stimulate algal blooms. Plant beds stabilize soft lake and river bottoms and reduce shoreline erosion by reducing the effect of waves and current.
Aquatic plants serve as spawning habitat for fish and amphibians, as shelter for various life stages of a variety of animal species, and as nesting habitat for birds. Plant beds support populations of aquatic insects that serve as a food base for other species. Healthy native aquatic plant communities also help prevent the establishment of invasive exotic plants like Eurasian water-milfoil (Myriophyllum spicatum).
Defining Characteristics and Similar Communities
Submergent marshes may contain similar species as floating-leaved marshes but have less than 50% relative cover of floating-leaved aquatic plants. While they often occur adjacent to or intergrade with emergent marshes and wild rice marshes, they are dominated by submersed species rather than emergent plants like cattails, bulrushes, and wild rice. Submergent marshes are also closely related to oligotrophic marshes but lack the abundance of rosette-forming aquatic macrophytes that characterizes that community.
The following Species of Greatest Conservation Need are listed according to their level of association with the Submergent Marsh natural community type, based on the findings in Wisconsin's 2015 Wildlife Action Plan.
Scores: 3 = high association, 2 = moderate association, and 1 = low association. See the key to association scores for complete definitions.
| Amphibians | Score | |
|---|---|---|
| Blanchard's Cricket Frog | Acris blanchardi | 3 |
| Mink Frog | Lithobates septentrionalis | 3 |
| Pickerel Frog | Lithobates palustris | 3 |
| Beetles | Score | |
|---|---|---|
| A Predaceous Diving Beetle | Agabus aeruginosus | 2 |
| Birds | Score | |
|---|---|---|
| Whooping Crane | Grus americana | 3 |
| American Black Duck | Anas rubripes | 2 |
| Black Tern | Chlidonias niger | 2 |
| Black-crowned Night-Heron | Nycticorax nycticorax | 2 |
| Forster's Tern | Sterna forsteri | 2 |
| Great Egret | Ardea alba | 2 |
| Red-necked Grebe | Podiceps grisegena | 2 |
| Yellow-crowned Night-Heron | Nyctanassa violacea | 2 |
| Caspian Tern | Hydroprogne caspia | 1 |
| Common Goldeneye | Bucephala clangula | 1 |
| Common Tern | Sterna hirundo | 1 |
| Least Bittern | Ixobrychus exilis | 1 |
| Dragonflies and damselflies | Score | |
|---|---|---|
| Spatterdock Darner | Rhionaeschna mutata | 3 |
| Sphagnum Sprite | Nehalennia gracilis | 3 |
| Mottled Darner | Aeshna clepsydra | 2 |
| Painted Skimmer | Libellula semifasciata | 2 |
| Slaty Skimmer | Libellula incesta | 2 |
| Spangled Skimmer | Libellula cyanea | 2 |
| Lilypad Forktail | Ischnura kellicotti | 1 |
| Grasshoppers and allies | Score | |
|---|---|---|
| Delicate Meadow Katydid | Orchelimum delicatum | 1 |
| Mammals | Score | |
|---|---|---|
| Big Brown Bat | Eptesicus fuscus | 2 |
| Little Brown Bat | Myotis lucifugus | 2 |
| Northern Long-eared Bat | Myotis septentrionalis | 2 |
| Silver-haired Bat | Lasionycteris noctivagans | 2 |
| Reptiles | Score | |
|---|---|---|
| Blanding's Turtle | Emydoidea blandingii | 3 |
| Queensnake | Regina septemvittata | 3 |
| Wood Turtle | Glyptemys insculpta | 2 |
| Eastern Massasauga | Sistrurus catenatus | 1 |
Please see Section 2. Approach and Methods of the Wildlife Action Plan to learn how this information was developed.
The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.
| Scientific Name | Common Name | Score |
|---|---|---|
| Armoracia lacustris | Lake Cress | 3 |
| Callitriche hermaphroditica | Autumnal Water-starwort | 3 |
| Callitriche heterophylla | Large Water-starwort | 3 |
| Didiplis diandra | Water-purslane | 2 |
| Eleocharis robbinsii | Robbins' Spike-rush | 2 |
| Littorella uniflora | American Shoreweed | 3 |
| Najas gracillima | Thread-like Naiad | 3 |
| Potamogeton bicupulatus | Snail-seed Pondweed | 3 |
| Potamogeton confervoides | Algae-leaved Pondweed | 3 |
| Potamogeton diversifolius | Water-thread Pondweed | 3 |
| Potamogeton hillii | Hill's Pondweed | 3 |
| Potamogeton oakesianus | Oakes' Pondweed | 3 |
| Potamogeton perfoliatus | Clasping-leaf Pondweed | 3 |
| Potamogeton pulcher | Spotted Pondweed | 3 |
| Potamogeton vaseyi | Vasey's Pondweed | 3 |
| Schoenoplectus torreyi | Torrey's Bulrush | 2 |
| Stuckenia filiformis ssp. alpina | Northern Slender Pondweed | 3 |
| Stuckenia filiformis ssp. occidentalis | Slender Pondweed | 3 |
| Stuckenia vaginata | Sheathed Pondweed | 3 |
| Utricularia resupinata | Northeastern Bladderwort | 2 |
The following Ecological Landscapes have the best opportunities to manage for Submergent Marsh, based on the Ecological Landscapes of Wisconsin Handbook.
| Ecological Landscape | Opportunity |
|---|---|
| Central Sand Hills | Major |
| North Central Forest | Major |
| Northern Highland | Major |
| Northwest Sands | Major |
| Superior Coastal Plain | Major |
| Western Coulee and Ridges | Major |
| Central Lake Michigan Coastal | Important |
| Central Sand Plains | Important |
| Forest Transition | Important |
| Northeast Sands | Important |
| Northern Lake Michigan Coastal | Important |
| Northwest Lowlands | Important |
| Southeast Glacial Plains | Important |
| Western Prairie | Important |
| Southern Lake Michigan Coastal | Present |
| Southwest Savanna | Present |
Major (3 on map)
A major opportunity for sustaining the natural community in the Ecological Landscape exists, either because many significant occurrences of the natural community have been recorded in the landscape or major restoration activities are likely to be successful maintaining the community's composition, structure, and ecological function over a longer period of time.
Important (2 on map)
Although the natural community does not occur extensively or commonly in the Ecological Landscape, one to several occurrences do occur and are important in sustaining the community in the state. In some cases, important opportunities may exist because the natural community may be restricted to just one or a few Ecological Landscapes within the state and there may be a lack of opportunities elsewhere.
Present (1 on map)
The natural community occurs in the Ecological Landscape, but better management opportunities appear to exist in other parts of the state.
Conservation actions respond to issues or threats, which adversely affect species of greatest conservation need (SGCN) or their habitats. Besides actions such as restoring wetlands or planting resilient tree species in northern communities, research, surveys and monitoring are also among conservation actions described in the WWAP because lack of information can threaten our ability to successfully preserve and care for natural resources.
Threats/issues and conservations actions for natural communities
The following are additional considerations for Submergent Marsh in Ecological Landscapes with opportunities for protection, restoration, and/or management. For more information, see the Wildlife Action Plan.
This Ecological Landscape is heavily developed for agricultural, industrial, and residential purposes. There are continuing effects from past management decisions (e.g., filling of marshes, loss of wild rice). Sedimentation, weed removal, and the use of pesticides can damage marsh habitat and encourage the growth and spread of invasives.
Runoff from agricultural activities adjacent to streambanks and stormwater from urban areas tops the list of non-point source pollution sources in the Central Sand Hills. These sources of pollutants degrade or otherwise threaten many streams, lakes, wetlands and/or groundwater. Additional considerations for submergent aquatic communities in the Central Sand Hills Ecological Landscape are listed below.
The hydrology throughout much of the Central Sand Plains has been altered by a maze of dikes, drainage ditches, canals, and constructed impoundments. High acidity and low fertility makes the waters of this Ecological Landscape generally inhospitable to aquatic vegetation. Among the exceptions, though, are several plant species that are adapted to such conditions, such as Farwell's milfoil and twin-stemmed bladderwort, which are locally common in several of the impoundments in the western part of the Ecological Landscape. Most of the impoundments on public lands were originally constructed to benefit waterfowl, something they're not always well-suited for because of the chemical nature of the waters. Others were developed to provide a constant source of water for the cranberry industry, which is a major economic concern in this region. Backwaters of the Wisconsin and Yellow Rivers contain more familiar assemblages of pondweeds, coontail, waterweed, water lilies, watershield, and common bladderwort. Runoff from agricultural activities adjacent to streambanks and impoundments and stormwater runoff from urban areas are non-point pollution sources in the Central Sand Plains. These sources can degrade or otherwise threaten streams, impoundments, wetlands or groundwater. Assistance should be provided to farmers and cranberry growers for development of nutrient and pesticide management plans that help control non-point discharges within the watershed. Riparian residents and others should be encouraged to participate in self-help volunteer lake monitoring programs.
The more intact (i.e., forested) watersheds in this Ecological Landscape occur on the eastern and extreme northern margins. In other portions of this Ecological Landscape, agriculture is a major land use and associated practices can result in soil erosion and water quality problems. Invasive plants may replace native plants and affect the composition of aquatic communities. Submergent marsh occurs in quiet bays of some of the Ecological Landscapes lakes, and in the backwaters of larger rivers such as the Wisconsin and its tributaries. Impoundments are common in the Wisconsin River system, and some of them do provide suitable conditions for the development of submergent marsh.
This community type is present in the deeper, quiet bays of many lakes, in some of the region's low gradient streams, and also in impoundments, such as the Gile Flowage (Iron County), the Chippewa Flowage (Sawyer County) and the Mondeaux Flowage (Taylor County). Invasives such as Eurasian water-milfoil and curly pondweed are problems in parts of this Ecological Landscape.
Good examples of submergent marsh occur in lakes and stretches of low-gradient streams, especially within some of the public lands in the Ecological Landscape.
This community type is present in many lakes and low gradient streams, as well as in impoundments such as Thunder Marsh (Oneida County), Turtle-Flambeau Flowage (Iron County), Rainbow Flowage and nearby stretches of the Upper Wisconsin River (Oneida County), and Willow Flowage (Oneida County). Development pressures are very high in this Ecological Landscape and there is a need to protect undeveloped shorelines in the near future. Rusty crayfish have significantly impacted lakes in this Ecological Landscape.
The Lower Wolf River Bottomlands (Shawano and Outagamie Counties), Oconto River Marsh (Oconto County), Peshtigo Harbor Marsh (Marinette County) and Green Bay West Shore Wetlands (Oconto County) contain examples of this community. Uplands should be buffered and shorelines should be managed to prevent erosion and sedimentation, and limit input of pollutants (including through pathways associated with the underground aquifers and fractured dolomite bedrock that underlies the Door Peninsula). Disturbance of polluted sediments buried in the bottoms of Green Bay and the larger rivers should be avoided.
The Trade River Wetlands (Polk and Burnett Counties) are an example of this community type. Most problems are associated with the larger developed lakes, where invasive plants (e.g., purple loosestrife) have replaced natives and shoreline habitat has been developed. This type is less common in this Ecological Landscape than elsewhere. Peatlands are the major wetland community types here.
This community type is present in quiet bays of many lakes in this Ecological Landscape, along certain stretches of low gradient streams, and in impoundments such as Gordon Flowage (Douglas County), Phantom Flowage on Crex Meadows State Wildlife Area (Burnett County), Amsterdam Sloughs State Wildlife Area (Burnett County), and the Clam River Flowage (Burnett County). Development pressures on shorelines are very high here and there is a need to protect more undeveloped lakes.
There are continuing impacts from past management decisions (e.g., draining and filling marshes and loss of wild rice). Additional considerations for submergent aquatic communities in the Southeast Glacial Plains Ecological Landscape are listed below.
Submergent aquatic communities are primarily associated with coastal embayments and estuaries on Lake Superior. Inland lakes are scarce in this Ecological Landscape. Additional considerations for submergent aquatic communities in the Superior Coastal Plain Ecological Landscape are listed below.
The Mississippi River corridor, including its associated marshes and floodplain, is of continental importance to migratory waterfowl. The series of dams constructed on the Mississippi in the early part of the Twentieth Century severely disrupted the natural periodicity and magnitude of floods. While marsh habitat has been created in some areas, much of the sediment load that was formerly carried downstream is now deposited in the backwaters, filling them in and shortening the natural life of the aquatic beds. The submergent marsh community is now well-developed in some backwaters of the large rivers (e.g., Mississippi, Wisconsin, Chippewa, and Black Rivers). It provides an important fish nursery. Significant examples due to their size and importance to migratory waterfowl, other birds, turtles, and fish exist at several locations on the Mississippi River. Restoration efforts are taking place in areas such as Lake Onalaska, which is being replanted with wild celery. Wild celery is a favorite food plant of the canvasback duck, which stops here in vast numbers along with many other waterfowl species during migration periods. Good examples of marshes dominated by American lotus occur at Trempealeau National Wildlife Refuge (Trempealeau County) and Bertom Lake (Grant County). Additional considerations for submergent aquatic communities in the Western Coulees and Ridges Ecological Landscape are listed below.
This community is found in backwaters of the St. Croix River, and in some prairie pothole lakes and ponds. Past agricultural practices have detrimentally impacted this community, and soil and water quality are still being affected in negative ways. Sedimentation is damaging aquatic beds and detrimentally impacting migratory waterfowl. Additional considerations for submergent aquatic communities in the Western Prairie Ecological Landscape are listed below.
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St. Louis River Marshes above Oliver. Submergent marsh with Potamogeton nutans.
Photo by Eric Epstein.
White water-lily (Nymphaea odorata) and "island" with beaked bladderwort (Utricularia cornuta) and round-leaved sundew (Drosera rotundifolia). Julian Bay Lagoon.
Photo by Emmet Judziewicz.
Stretches of this free-flowing warmwater stream support lush, diverse beds of submergent aquatic vegetation. Rice Creek, Northern Highland Ecological Landscape.
Photo by Eric Epstein.
Rich beds of aquatic plants including Potamogeton spp. and Elodea sp. Rice Creek, Vilas County.
Photo by Eric Epstein.
Submergent marsh countaining various plants in Bayfield, Wisconsin.
Photo by Brenton Butterfield.
Note: photos are provided to illustrate various examples of natural community types. A single photograph cannot represent the range of variability inherent in a given community type. Some of these photos explicitly illustrate unusual and distinctive community variants. The community photo galleries are a work in progress that we will expand and improve in the future.