region K Area 91B larger picture

Wisconsin and Minnesota Sandy Outwash

Eastern half of area in Superior Upland Province of Laurentian Upland.
Western half of area in Western Lake Section of the Central Lowland Province of the Interior Plains.

Area in Wisconsin is 60%
Area in Minnesota is 40%

Total Land Area 4,100 square miles (10,650 square kilometers)

Towns/cities include:
Spooner, Grantsburg, Solon Springs, Siren, Wisconsin
North Branch, Princeton, Zimmerman Minnesota

Far northern part includes parts of Chequamegon National Forest. All of Crex Meadows Wildlife Area in this part.


Precambrian and Cambrian sandstone bedrock underlies most glacial deposits. Bedrock consists of Keweenawan sandstone in northern part and Cambrian sandstone with dolomite and shale in southern part. In most areas, bedrock covered by Pleistoncene deposits as deep as 330 feet (100 meters). Bedrock exposures occur in some areas along St. Croix River. Most Pleistocene deposits are late Wisconsin in age.

Much of area nearly level to gently sloping with some steeper escarpments along streams, rivers and lake borders. Area characterized by outwash plains, some pitted or collapsed, and by small moraines, dunes, lake plains, swamps, bogs and marshes. Lakes are common and streams generally form a dendritic pattern.

Topography -

Elevation ranges from about 800 feet (245 meters) to 1,500 feet (455 meters). Local relief typically a few meters.


Average annual preciptitation is 25 - 34 inches (635 to 865 millimeters)
66% of rainfall occurs as convective thunderstorms during growing season.
Average annual temperature is 38 - 46 degrees F (3 to 8 degrees C)
Freeze free period averages around 150 days (ranges 120 - 180 days) Can be as short as 90 days in northern part.

Major Hydrologic Unit Areas

Name Code Extent*
St. Croix (0703) 69%
Mississippi Headwaters (0701) 20%
Western Lake Superior (0401) 11%

* this is the percent of area drained by each named hydrologic unit

The St. Croix, Namekagon, Rum, and Yellow Rivers are major rivers that drain this MLRA.

The St. Croix River is a National Scenic River, and the Rum River is a National Wild and Scenic River.


Estimated withdrawls in this MLRA:
Public supply surface water 6.3% ground water 6.4%
Livestock surface water 0.3% ground water 0.2%
Irrigation surface water 1.2% ground water 5.5%
Other surface water 74.8% ground water 5.3%

Total Average Daily Withdrawls:
Total daily withdrawls average 570 million gallons per day (2,155 million liters per day)
17% ground water sources
83% surface water sources

Surface water and ground water very abundant and readily available. Normal precipitation years inadequate for crops and pasture on sandy soils. Dry years result in serious crop reduction yields.

Drainage of soils on lowlands needed for field crops and tame pasture plants commonly grown in area. Irrigation widely used for high-value crops.

Glacial deposits primary source of ground water. Quality of water is good. Level of total dissolved solids less than 150 ppm (milligrams per liter). Main components are calcium, magnesium and bicarbonate ions. Locally, dissolved mineral content can be high if high limestone content of glacial deposits. Some areas have high iron concentrations.

Surface water sources are lakes and streams. Water quality generally good. Most lakes and streams clear, but those that receive deposits of organic material from wetland vegetation are tinted brown

Ground water yields from all aquifers range from 100 to more than 1,000 gallons per minute (380 to more than 3,785 liters per minute).

Good quality ground water available from sedimentary rocks in Minnesota part of area.
Aquifers include St Peter and Prairie du Chien sandstone and dolomite Ironton-Galsevill sandstone and the Mount Simon-Hinckley sandstone.
Water from these aquafirs averages 250 to 350 ppm (milligrams per liter) total dissolved solids. All have calcium-magnesium-bicarbonate type water that is hard. The St. Peter aquifer is not as utilized because good aquifers occur above it.

Surface water pollution minimal due to relative undeveloped areas. Locally, extensive cottage and home building along lakes/streams is potental problem. Effluent from sewage disposal can pollute water and cause weeds and algae growth, especially severe in seepage lakes with little water exchange.

Area has three lake types, Spring Lakes fed by groundwater, and have high mineral from ground water sources. Has similar reaction as ground water reaction.
Seepage lakes generally do not have an inlet or outlet by may have an intermittent outlet. Water level maintained by water table or well sealed bottom. Very low mineral content. Generally acidic (PH less than 7).
Drainage Lakes have an outlet and at least one inlet. Main water source is runoff from streams. Lower mineral content than Spring Lakes, but higher than seepage lake mineral content. Have greatest range in reation. Some drainage lakes are alkaline (PH higher than 7).

80% of lakes have PH less than 7.0


  • Soils have a frigid soil temerature regime.
  • Udic or aquic soil moisture regime and mixed or isotic mineralogy.
  • Soils on uplands are very deep, excessively drained to somewhat poorly drained and sandy.
  • Soils on lowlands are very deep, poorly drained or very poorly drained, and sandy or mucky.
  • Dominant Soils:

  • Alfisols
  • Entisols
  • Histosols
  • Spordosols
  • Great Group Series Location
    Udipsamments Cantlin, Graycalm, Grayling, Menahga, Mahtomedi, Grettum, Friendship, Wurtsmith, Zimmerman, Shawano, Crex, Lino series formed in sandy outwash or windblown sediments
    Hapludalfs Karlsborg, Meenon, Perida series formed in sandy outwash or windblown sediments over lacustrine clay on old glacial lake plains
    Hapludalfs Dairyland, Bigisland series
    Psammaquents Newson series formed in sandy outwash in depressions on outwash plains
    Endoaquods Kinross, Au Gres series formed in sandy outwash in depressions on outwash plains
    Haplosaprists Markey, Seelyeville,Dawson, Loxley series formed in sapric material in marshes and in bogs
    Udipsamments Winterfield series formed on floodplains
    Fluvaquents Totagatic series formed in sandy alluvium
    Haplosaprists Bowstring series formed in sapric material

    Fauna and Flora

    Mixed coniferous-deciduous forest. Jack pine and scrub (Hill's) oak are dominant trees. Barrens are common. Poorly drained soils support black spruce, tamarack, speckled alder, willow and sedges.

    Major wildlife species include white-tailed deer, black bear, wolf, ruffed grouse, sharp-tailed grouse. Red fox, bobcat, coyote, fisher, mink, otter, and beaver.

    Land Use

    20% - Cropland - private
    7% - Grassland - private
    3% - - Federal
    43% - Forest - private
    3% - - Federal
    11% - Urban development - private
    6% - Water - private
    1% - - Federal
    6% - Other - private

    Nearly 50 percent of this area is forested. Two-thirds of the forestland consists of national and State forests and large, privately owned holdings, and one-third consists of small, privately owned holdings. The forestland is primarily in the eastern part of the MLRA, and it supports a pulp and timber industry and is used for recreational activities.

    28% mostly in western part used for agriculture. Irrigated corn, soybeans and vegetable crops (potatoes, snap beans and peas) and forage and feed grains for dairy cattle and other livestock are principal crops. Cranberries are grown on some wet soils.

    Major resource concerns are water quality, nutrient management, improper grazing management and wind erosion.

    Substantial acreage in southern part urban and expanding rapidly.

    Major resource concerns are water erosion, wind erosion, wetness, soil fertility, soil tilth, water quality.

    Conservation practices include crop rotation, crop residue management. Cover crops are sometimes planted with low-residue canning crops. Nutrient management and pest management are important for water quality concerns especially on irrigated cropland. Prescribed grazing and pasture and hayland planting improve pastures and grazing management. Forest stand improvement and forest trails and landings reduce impact of timber management activities on water quality.

    Return to the Regional Land Use Main Page Here