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Great Lakes Lakeshore Prairie

EVT 7411Great Lakes Wet-Mesic Lakeplain Prairie

CES202.027GNRHerbRiparian

Summary

This system is found on the lakeplain near the southern central Great Lakes of the United States and Canada. Stands occur on level, sandy glacial outwash, sandy glacial lakeplains, and deposits of dune sand in silty/clayey glacial lakeplains. The soils are sands and sandy loams, loams with poor to moderate water-retaining capacity, typically occurring over less permeable silty clays . There is often temporary inundations after heavy rains or in the spring, followed by dry conditions throughout much of the remaining growing season. The vegetation of this system is dominated by graminoid species typically 1-2 m high. Trees and shrubs are very rare. There is very little bare ground. Andropogon gerardii, Calamagrostis canadensis, Carex spp. (Carex aquatilis, Carex bicknellii, Carex buxbaumii, Carex pellita), Panicum virgatum, Spartina pectinata, Schizachyrium scoparium, and Sorghastrum nutans are the most abundant graminoid species. Many of the sites that this system formerly occupied are now urban and/or agricultural. Areas around Chicago and Detroit were likely in this system but are heavily converted now and few sites remain. Remnant sites have been impacted by woody encroachment of native and non-native species.

Source: NatureServe Explorer

Vegetation

The vegetation of this system is dominated by graminoid species typically 1-2 m high. Trees and shrubs are very rare. There is very little bare ground. Andropogon gerardii, Calamagrostis canadensis, Carex spp. (Carex aquatilis, Carex bicknellii, Carex buxbaumii, Carex pellita (= Carex lanuginosa)), Panicum virgatum, Spartina pectinata, Schizachyrium scoparium, and Sorghastrum nutans are the most abundant graminoid species. Many of the sites that this system formerly occupied are now urban and/or agricultural. Areas around Chicago and Detroit were likely in this system but are heavily converted now and few sites remain. Remnant sites have been impacted by woody encroachment of native and non-native species.

Source: NatureServe Explorer

Environment

Stands occur on level, sandy glacial outwash, sandy glacial lakeplains, and deposits of dune sand in silty/clayey glacial lakeplains. The soils are sands, sandy loams, and loams with poor to moderate water-retaining capacity and typically occur over less permeable silty clays. The shallow, less permeable silty clays and the flat landscape combine to favor temporary inundations after heavy rains or in the spring. The coarser surface soils then dry out throughout much of the remaining growing season. These occurred in a patchy landscape of both drier oak woodland/savanna and more mesic beech-maple forest. Pin oak depressions were common in these prairies.

Source: NatureServe Explorer

Dynamics

The cycle of soils being temporarily inundated and then drying out during the growing season is important for this system. Great Lakes water levels also affected this system with longer-term increases and decreases creating wetter and drier baseline conditions, respectively. Graminoids and forbs can thrive under these conditions but woody species are inhibited. The dry conditions and abundance of herbaceous vegetation creates conditions well-suited for burning and fires further reduced woody vegetation. Drier sites and those in a drier landscape burned more frequently. Fires were most likely in dry years after a productive year(s) when biomass was higher. Fire regime was probably related to the adjacent oak savannas but likely a little less frequent. Water levels were highly variable and boundaries of this system probably shifted across the landscape in response to fire, Great Lakes water levels, and wetter or drier climatic cycles.

Source: NatureServe Explorer

Threats

The primary threat to this system is drainage followed by conversion to agriculture or urban/infrastructure development. This system was concentrated in highly developed areas of the Midwest near what is now metropolitan Detroit, Chicago, Milwaukee, and northern Indiana. From the early 1800s to the 1990s, more than 99% of presettlement Great Lakes Wet-Mesic Lakeplain Prairie (CES202.027) was destroyed (Comer et al. 1995b). Expanding urban infrastructure and alterations to drainage patterns continue to threaten remaining sites. In addition to the direct effects of conversion of this system, landscape fragmentation from conversion of this or other related natural systems affects remaining stands by further reducing the opportunities for landscape-level fires, increasing the opportunities for exotic species to invade from nearby populations, and reducing the amount of suitable habitat that can be converted to this system as part of the natural fluid response to fire, Great Lakes water levels, and precipitation. Invasive species that threaten the diversity and vegetative structure in lakeplain wet-mesic prairie include Elaeagnus umbellata, Frangula alnus (= Rhamnus frangula), Lythrum salicaria, Phalaris arundinacea, Phragmites australis, Rhamnus cathartica, Rosa multiflora, Typha angustifolia, and Typha x glauca (Kost et al. 2007).

Source: NatureServe Explorer

Distribution

This system is found near the southern central Great Lakes of the United States and Canada, from southeastern Wisconsin and northeastern Illinois to southern Michigan and southwestern Ontario. This does not go farther east than northwestern Ohio (glacial Lake Maumee).

Source: NatureServe Explorer

Ecologically Associated Plant Species

Plant species that characterize this ecosystem type, organized by vegetation stratum. These are species ecologically associated with the ecosystem, not confirmed present in any specific area.

Herb (field)

Andropogon gerardi, Calamagrostis canadensis, Carex aquatilis, Carex bicknellii, Carex buxbaumii, Carex pellita, Eleocharis wolfii, Panicum virgatum, Platanthera leucophaea, Schizachyrium scoparium, Sorghastrum nutans, Spartina pectinata

Source: NatureServe Ecological System assessment

Ecologically Associated Animals (6)

Animal species ecologically associated with this ecosystem type based on NatureServe assessment. These are species whose habitat requirements overlap with this ecosystem, not confirmed present in any specific roadless area.

Reptiles (4)

Common Name	Scientific Name	G-Rank
Kirtland's Snake	Clonophis kirtlandii	G2
North American Racer	Coluber constrictor	G5
Eastern Milksnake	Lampropeltis triangulum	G5
Dekay's Brownsnake	Storeria dekayi	G5

Amphibians (1)

Common Name	Scientific Name	G-Rank
American Toad	Anaxyrus americanus	G5

Butterflies & Moths (1)

Common Name	Scientific Name	G-Rank
Blazing Star Stem Borer	Papaipema beeriana	G3?

Source: NatureServe Ecological System assessment

At-Risk Species Associated with this Ecosystem (3)

Species with conservation concern that are ecologically associated with this ecosystem type. G-Rank indicates global conservation status: G1 (critically imperiled) through G5 (secure). ESA status indicates U.S. Endangered Species Act listing.

Common Name	Scientific Name	G-Rank	ESA Status
Kirtland's Snake	Clonophis kirtlandii	G2	--
Blazing Star Stem Borer	Papaipema beeriana	G3?	--
Eastern Prairie White-fringed Orchid	Platanthera leucophaea	G2G3	Threatened

Source: NatureServe Ecological System assessment

Component Associations (4)

Plant community associations that occur within this ecological system. Associations are the finest level of the U.S. National Vegetation Classification (USNVC) and describe specific, repeating assemblages of plant species. Each association represents a distinct community type that may be found where this ecosystem occurs.

Name	G-Rank
Andropogon gerardii - Calamagrostis canadensis - Pycnanthemum virginianum - Oligoneuron ohioense Wet Meadow	G2	NatureServe
Andropogon gerardii - Sorghastrum nutans - Schizachyrium scoparium - Aletris farinosa Grassland	G2	NatureServe
Quercus alba - Quercus velutina - Quercus palustris / Carex pensylvanica Grassy Woodland	G2	NatureServe
Spartina pectinata - Carex spp. - Calamagrostis canadensis Lakeplain Wet Meadow	G2	NatureServe

State Conservation Ranks (5)

Subnational conservation status ranks (S-ranks) assigned by Natural Heritage Programs in each state where this ecosystem occurs. S1 indicates critically imperiled at the state level, S2 imperiled, S3 vulnerable, S4 apparently secure, and S5 secure. An ecosystem may be globally secure but imperiled in specific states at the edge of its range.

State	S-Rank
IL	SNR
IN	SNR
MI	SNR
OH	SNR
WI	SNR

Methodology and Data Sources

Ecosystem classification: Ecosystems are classified using the LANDFIRE 2024 Existing Vegetation Type (EVT) layer, mapped to NatureServe Terrestrial Ecological Systems via a curated crosswalk. Each EVT is linked to the USNVC (U.S. National Vegetation Classification) hierarchy through pixel-level co-occurrence analysis of LANDFIRE EVT and NatureServe IVC Group rasters across all roadless areas.

Vegetation coverage: Coverage percentages and hectares are derived from zonal statistics of the LANDFIRE 2024 EVT raster intersected with roadless area boundaries.

Ecosystem narratives and community species: Sourced from the NatureServe Explorer API, representing professional ecological assessments of vegetation composition, environmental setting, dynamics, threats, and characteristic species assemblages.

IVC hierarchy: The International Vegetation Classification hierarchy is sourced from the USNVC v3.0 Catalog, providing the full classification from Biome through Association levels.

Component associations: Plant community associations listed as components of each NatureServe Ecological System. Association data from the NatureServe Explorer API.

State ranks: Conservation status ranks assigned by NatureServe member programs in each state where the ecosystem occurs.