Forest Glacial Marshes of Central Minnesota

Series Description

 

Wetlands occurring in upland depressions of the hardwood forest landscapes (Northern Hardwood Forest Ecoregion) were considered in this series identified as Forest Glacial Marshes. The wetlands of this series have seasonal to semi-permanent hydrologic regimes. All basins selected were formed on glacial till or outwash and have calcareous waters. The Northern Hardwood Forest Ecoregion includes many types of land uses, including the rapidly urbanizing Minneapolis/St. Paul metropolitan area, agricultural and rural lands on the exurban fringe, and remnant forested landscapes in public lands, preserves, and regional parks.

Plant communities of these wetlands are typically emergent marsh communities with a wet meadow transitional zone. Sedges (Carex spp.), cattails (Typha spp.), arrowheads (Sagittaria spp.), and a variety of additional forbs and graminoids are common to these wetlands. Flood tolerant woody species, such as white ash (Fraxinus americana), willows (Salix spp.), and dogwoods (Cornus spp.), are occasionally present as well.

Considerable effort was put into site selection for this series, considering the complex surficial geology of the Minneapolis/St. Paul metropolitan area and adjacent counties, and complex land use impacts associated with urbanizing landscapes. Basin sizes ranged from 1.5 to 14 acres, and watershed areas ranged from 20 acres in relatively undisturbed landscapes, to as much as 750 acres for highly connected urban basins. Wetlands that were tiled or drained by ditches were dropped from consideration in this study because agricultural drainage is the main gradient of the Prairie Glacial Marsh series. Urban wetlands in this series exhibit high volumes of stormwater runoff, and often have modified inlets and outlets for flood control purposes. Other urban impacts include past filling and basin modifications, road encroachment on wetland basins, and reduction of watershed area due to landscape fragmentation and development.

Sites chosen for this study met the following criteria:

How sites were selected to form a land-use gradient:

Since this series includes a highly urbanized region, the main land use gradient is stormwater impacts related to the amount of impervious surfaces in the watersheds. Three sites, Eden Prairie Industrial (EP), Rosemount (RO), and Maplewood (MA) receive high stormwater inputs. The Maplewood site is surrounded by parking lots of a shopping mall. The Willow Ridge (WR) and Inver Grove Heights sites (IG) are somewhat less impacted but still are within a residential context. The Hennepin Park (HP) site is encompassed by parkland, but is significantly impacted by adjacent residential development. The remaining sites have less urbanized use in their immediate vicinity. Kelly Farm (KF), Kenna (KE), and Lashier (LA) are adjacent to agriculture (with pasturing at Kelly Farm), but have not been tilled or drained. Ordway Prairie (OP), and Grey Eagle (GE) are surrounded by prairie or second growth forest. All have some impacts from past agriculture. Moe Woods (MW), Crawford Woods (CW), and Wolsfeld Woods (WW) are the least impacted sites in this series, with apparently little past use and surrounding land that has likewise not been historically converted. Forty-three sites were considered for inclusion in this series. Twenty eight sites were not selected because they either were too large or were partially drained by tiles or ditches. Many of the sites located were suggested by city planners, Soil and Water Conservation District staff, US Fish and Wildlife staff, Minnesota Department of Natural Resources staff, and by staff of the Pollution Control Agency.

To view information on an individual site, select location (dot or code) on map:

Forest Glacial Marshes

Select Other Information for this Series

Indices of Biotic Integrity

Land Use and Environment Data

Biological Survey Data

Publications for this Series

Lehtinen, R.L., S.M. Galatowitsch, and J.R. Tester. Consequences of habitat loss and fragmentation for wetland amphibian assemblages. Accepted for publication in Wetlands

Whited, D.C. et al. The importance and influence of landscape characteristics on patterns of biodiversity in depressional wetlands. In review, Landscape Ecology

Galatowitsch, S.M. et al. The vegetation of wet meadows in relation to their land use. In Review, Environmental Monitoring and Assessment.

 

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