General information

Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.

Figure 1. Mapped extent

Areas shown in blue indicate the maximum mapped extent of this ecological site. Other ecological sites likely occur within the highlighted areas. It is also possible for this ecological site to occur outside of highlighted areas if detailed soil survey has not been completed or recently updated.

MLRA notes

Major Land Resource Area (MLRA): 099X–Erie-Huron Lake Plain

This area is in the Eastern Lake Section of the Central Lowland Province of the Interior Plains (USDA-NRCS, 2022). It is a nearly level glacial lake plain with a few scattered ridges of sand that represent past shorelines and moraines. The Saginaw, Clinton, and Huron Rivers empty into the Great Lakes in the part of the area in Michigan. The southern half of this area is covered with glacial deposits of till, lake sediments, and outwash from the Wisconsin and older glacial periods. The area also has some low moraines. Mississippian- to Silurian-age shale, limestone, and dolomite rocks are at or near the surface close to Lake Erie and Lake Huron. Sandstone comes near the surface in the Thumb area east of Saginaw Bay, and a sandstone headland exists on a short stretch of Lake Huron shoreline. An extensive swamp in proximity the Maumee River prevented overland travel prior to its drainage by early settlers. Remnant marshes are near the Lake Erie shore.

The dominant soils in this MLRA are Alfisols, Inceptisols, Mollisols, and Spodosols. The soils in the area dominantly have a mesic soil temperature regime, an aquic soil moisture regime, and mixed or illitic mineralogy. Most soils in MLRA 99 are very deep, generally somewhat poorly drained to very poorly drained, and loamy or clayey. Epiaqualfs (Blount, Hoytville, Nappanee, and Shebeon series) and Glossudalfs (Capac series) formed in till (some of which is dense) on till plains, moraines, and lake plains. Epiaquepts formed in loamy till on till plains and moraines (Kilmanagh series) and in lacustrine deposits on lake plains (Lenawee and Paulding series). Endoaquepts formed in lacustrine deposits on lake plains (Latty and Toledo series) and in loamy till on moraines (Parkhill series). Endoaquolls formed in outwash deposits on outwash plains and lake plains, in drainageways (Granby series), and in loamy till on till plains and moraines (Tappan series). Endoaquods (Pipestone series) formed in outwash deposits on outwash plains, lake plains, and beach ridges. Epiaquods (Wixom series) formed in sandy sediments over till or lacustrine deposits on till plains, outwash plains, and lake plains.

Broad flat areas of somewhat poorly drained soils support Landfire (2017) systems: North-Central Interior Beech-Maple Forest, with wetter patches of North-Central Interior Wet Flatwoods, and Central Interior and Appalachian Swamp. Sandy beach ridges and thin sand flats have Landfire (2017) systems: North-Central Interior Dry-Mesic Oak Forest and Woodland and Great Lakes Wet-Mesic Lakeplain Prairie. Central Interior and Appalachian Floodplain Systems occur adjacent to rivers that flow through the area. To the north, oak systems decline in coverage. Thin sandy flats in the north have Laurentian-Acadian Pine-Hemlock-Hardwood Forest. The north and south are best separated as ecological inference areas due to floristic and dominant vegetation contrasts which also correspond to generally lower summer and winter temperatures northward. This north-south break is approximated by the drainage divide between the Lake Huron and Lake Erie/Lake St. Clair basins.

Nearly three-fourths of this MLRA is in farms. About three-fifths of the area is cropland. The rest of the farmland is mostly in small farm woodlots, but some of the farmland is used for permanent pasture or other purposes. Cash crops are important. Corn, winter wheat, soybeans, and hay are the major crops. Sugar beets and canning crops also are important. Some fruit and truck crops are grown on the coarse textured soils. Dairying is an important enterprise on some farms near the larger cities. Almost one-fifth of the area is used for urban development. Shiawassee National Wildlife Refuge, Cedar Point National Wildlife Refuge, Oak Openings Preserve Metropark (Ohio) are among the more notable conservation lands.

Summary of existing land use (South):
Upland Forest (7%)
Hardwood (6%)
Agricultural (60%)
Developed (28%)

Summary of existing land use (North):
Upland Forest (14%)
Hardwood (13%)
Agricultural (58%)
Developed (13%)
Swamps and Marshes (13%)

Classification relationships

The USFS ecoregion classification (Cleland et al., 2007) for the majority of MLRA 99 is the Humid Temperate, Hot Continental Division, Midwest Broadleaf Forest Province 222, Lake Whittlesey Glaciolacustrine Plain Section 222U. The ecoregion subsection composition is 222Ud (Sandusky Lake Plain) and 222Ue (Saginaw Clay Lake and Till Plain) in the north near Lake Huron and Saginaw Bay. In the south near Lake Erie, the area is composed of subsections 222Ua (Maumee Lake Plain), 222Ub (Paulding Plains), and 222Uc (Marblehead Drift/Limestone Plain). A mix of interlobate deposits extends into MLRA 99 as subsection 222Jf (Lum Interlobate Moraine) of South Central Great Lakes Section 222J. Sandy deposits extend south from adjacent MLRA are part the Warm Continental Division, Laurentian Mixed Forest Province 212, Northern Lower Peninsula Section 212H, subsection 212Hh (Gladwin Silty Lake Plain).

The Saginaw Bay and Lake Huron lake plains is coextensive with EPA ecoregion 57e (Saginaw Lake Plain) (Omernik and Griffith, 2014). The majority of the Lake Erie or Maumee Lake Plain includes EPA ecoregion 57a (Maumee Lake Plain), extending east to include 57d (Marblehead Drift/Limestone Plain). Large inclusions of sand are delineated as ecoregion 57b (Oak Openings). A significant area of higher clay is designated as 57c (Paulding Plains).

Ecological site concept

The central concept of the Lake Plain Flats is loamy to clayey wave reworked till or fine lacustrine deposits often, but not exclusively with a seasonally high water table (somewhat poorly drained) due to a often dense layer of very low saturated hydraulic conductivity near the surface. Site is generally found in extensive flats. Vegetation is usually rich and mesophytic due to the high base parent material, high available water holding capacity, and slow drainage. However, the generally low precipitation and periodic drought made the area subject to fire and formation of prairies and savannas.

Associated sites

Similar sites

Table 1. Dominant plant species