Natural Resources
Conservation Service
Ecological site F091XY005WI
Wet Sandy and Loamy Lowland
Last updated: 9/27/2023
Accessed: 12/21/2024
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.
MLRA notes
Major Land Resource Area (MLRA): 091X–Wisconsin and Minnesota Sandy Outwash
The Wisconsin and Minnesota Sandy Outwash MLRA is the most extensive glacial outwash system in the northern half of Wisconsin. The total land area of the Wisconsin portion is just under 1.4 million acres (2,170 sq miles). The northern half is a former spillway for Glacial Lake Duluth. The flowing meltwater from the draining lake has left behind thick deposits of drift and carved a terraced river valley now occupied by the St. Croix and Bois Brule Rivers.
The northeastern section – the Bayfield hills – is a collapsed outwash plain where drift deposits are thick. Lacustrine materials from Glacial Lake Duluth line the northeastern tip. Moving southwest, the landscape transitions into a large pitted outwash plain. This is an area of extensive kettle holes, and, where the underlying till is less permeable, kettle lakes with some interspersed morainic hills and ridges. The glacial drift deposits are thinner in the southwestern section, although there is still no documented surface bedrock within this MLRA.
The St. Croix and Bois Brule rivers share a channel that lines much of the northwestern border of this MLRA. In some places, the underlying reddish-brown sandy loam till of the Copper Falls Formation is exposed along cut riverbanks, though most of it is covered by a mantle of outwash. Glacial lakes deposited pockets of fine-textured lacustrine materials, most of which were washed away or buried by glacial outwash and meltwater flowing through the channel. East of the channel, some of the silty and clayey lakebed deposits are found near the surface, where they impede drainage and contribute to the formation of extensive wetlands.
Historically, the area supported extensive jack pine (Pinus banksiana), scrub, and oak forests and barrens. The northern portion also supported stands of red pine (Pinus resinosa) and eastern white pine (Pinus strobus) as well. Marsh and sedge meadow, wet prairies, and lowland shrubs dominated the extensive wetland complexes in the southern tip of this MLRA (Finley, R., 1976).
Classification relationships
Relationship to Established Framework and Classification Systems:
Biophysical Settings (Landfire, 2014): This ES is largely mapped as Laurentian-Acadian Herbaceous Wetlands, Laurentian-Acadian Northern Hardwoods Forest, Laurentian Oak Barrens, Laurentian Pine Barrens, and Boreal Hardwood Forest
Wetland Forest Habitat Type Classification System for N. Wisconsin (Kotar and Burger, 2017) and Habitat Types of N. Wisconsin (Kotar, 2002): The sites of this ES keyed out to four habitat types: Fraxinus nigra/Onoclea (FnOn); Larix-Acer rubrum/Ilex (LArIx); Picea mariana-Larix/Nemopanthus (PmLNe); Acer saccharum/Sanguinaria-Impatiens (ASaI)
WDNR Natural Communities (WDNR, 2015): This ES is most similar to Northern Hardwood Swamp described by the WDNR, but may coincide with and overlap some of the WDNR wetland communities in different states depending on past hydrology.
Hierarchical Framework Relationships:
Major Land Resource Area (MLRA): Wisconsin and Minnesota Sandy Outwash (91X)
USFS Subregions: Bayfield Sand Plains (212Ka)
Small sections occur in the Mille Lacs Uplands (212Kb) and Hayward Stagnation Moraines (212Xf) subregions
Wisconsin DNR Ecological Landscapes: Northwest Sands, Northwest Lowlands
Ecological site concept
The Wet Sandy and Loamy Lowland ecological site is scattered throughout MLRA 91X but is most common in the southwest portion in depressions and drainageways on outwash and lake plains. These sites are characterized by very deep, very poorly or poorly drained soils that formed primarily in alluvium, outwash, and lacustrine deposits. Some sites have underlying dense loamy till. Sites are subject to occasional to frequent ponding in the spring and fall. Soils remain saturated for long periods during the growing season and meet hydric soil requirements. Soils range from very strongly acid to neutral. These sites are differentiated from other ecological sites by their drainage and texture. They have coarser texture than the Wet Clayey Lowlands and poorer drainage than other sandy and loamy sites. Clayey textures often have higher pH and available water capacity than sandy and loamy materials.
Associated sites
| F091XY001WI |
Poor Fen Poor Fen sites consist of deep organic deposits from primarily herbaceous origin. They are poorly or very poorly drained and are strongly to extremely acid. These sites occur in depressions that receive little stream or groundwater discharge. They are wetlands. They may be found adjacent to Wet Sandy and Loamy Lowland sites lower on the drainage sequence. |
|---|---|
| F091XY002WI |
Mucky Swamp Mucky Swamp sites consist of deep, highly decomposed organic matter, primarily of herbaceous origin. Some sites have mineral soil contact. They occur on drainageways, depressions, and floodplains that receive stream or groundwater discharge. They are very poorly drained and are neutral to strongly acid. They may be found adjacent to Wet Sandy and Loamy Lowland sites lower on the drainage sequence. |
| F091XY007WI |
Moist Sandy and Loamy Lowland These soils formed in sandy outwash, sandy lacustrine deposits, sandy eolian deposits, or loess that is sometimes underlain by sandy or loamy till. Soils are very deep and somewhat poorly drained. They are slightly drier and occur higher on the drainage sequence than Wet Sandy and Loamy Lowlands. |
| F091XY011WI |
Sandy Upland These soils formed primarily in sandy outwash or sandy eolian deposits, but some sites formed in sandy lacustrine or loamy alluvium underlain by sandy outwash. Soils are very deep and are moderately well or somewhat excessively drained. They are neutral to extremely acid and lack a spodic horizon. They are drier and occur higher on the drainage sequence than Wet Sandy and Loamy Lowlands. |
| F091XY012WI |
Loamy Upland These soils formed in loamy lacustrine, loamy alluvium, loamy till, sandy outwash, sandy eolian, or loess deposits. Some sites have underlying lacustrine deposits, till, or basalt bedrock. They are moderately well or well drained. They are drier and occur higher on the drainage sequence than Wet Sandy and Loamy Lowlands. |
| F091XY015WI |
Dry Upland These sites formed in sandy outwash or eolian deposits. Soils are very deep, excessively drained, and lack a spodic horizon. They are much drier and occur higher on the drainage sequence than Wet Sandy and Loamy Lowlands. |
Similar sites
| F091XY003WI |
Floodplain These sites occur in depressions and flats on floodplains. They form in sandy to silty alluvium and are somewhat poorly to very poorly drained. They are subject to flooding. Their vegetative communities may be very similar to those found on Wet Sandy and Loamy Lowlands. |
|---|---|
| F091XY006WI |
Wet Clayey Lowland These sites occur on depressions and drainageways on outwash plains and lake plains. They form in clayey lacustrine deposits overlain by sandy lacustrine or sandy outwash deposits. Like Wet Sandy and Loamy Lowlands, they are subject to some flooding. These are wetland soils. The vegetative communities they support may sometimes also be found on Wet Sandy and Loamy Lowlands. |
| F091XY002WI |
Mucky Swamp Mucky Swamps consist of deep, highly decomposed organic matter, primarily of herbaceous origin. Some sites have mineral soil contact. They occur on drainageways, depressions, and floodplains that receive stream or groundwater discharge. They are very poorly drained and are neutral to strongly acid. They host vegetative communities that are sometimes similar to those found on Wet Sandy and Loamy Lowlands. |
| F091XY007WI |
Moist Sandy and Loamy Lowland These soils formed in sandy outwash, sandy lacustrine deposits, sandy eolian deposits, or loess that is sometimes underlain by sandy or loamy till. Soils are very deep and somewhat poorly drained. The vegetative communities they support are somewhat similar to those found on Wet Sandy and Loamy Lowlands but with a preference for slightly drier conditions. |
Table 1. Dominant plant species
| Tree |
(1) Abies balsamea |
|---|---|
| Shrub |
Not specified |
| Herbaceous |
(1) Carex |
Click on box and path labels to scroll to the respective text.
Ecosystem states
State 1 submodel, plant communities
| 1.1A | - | Large-scale canopy disturbance, mortality in canopy layer. |
|---|---|---|
| 1.1C | - | Large-scale natural disturbance or tree harvesting, causing swamping of the site. |
| 1.2A | - | Slow accumulation of living and dead sphagnum moss layer. |
| 1.2B | - | Large-scale natural disturbance or tree harvesting, causing swamping of the site. |
| 1.3A | - | Colonization by trees with tolerance for prolonged ponding. |