LOCATION WAHLSTEN MNEstablished Series
TAXONOMIC CLASS: Coarse-loamy, isotic, frigid Oxyaquic Dystrudepts
TYPICAL PEDON: Wahlsten stony loam on a convex slope of 4 percent on a bedrock-controlled ridge under a mixed conifer forest. (Colors are for moist soil unless otherwise stated.)
A--0 to 3 inches; black (10YR 2/1) stony loam, very dark gray (10YR 3/1) dry; weak medium granular structure; very friable; many fine roots; 4 percent gravel, 4 percent cobbles, 10 percent stones; strongly acid; abrupt smooth boundary. (2 to 4 inches thick)
Bw1--3 to 9 inches; dark yellowish brown (10YR 4/4) stony loam; weak fine subangular blocky structure; friable; many fine roots; 5 percent gravel, 5 percent cobbles, 10 percent stones; strongly acid; clear smooth boundary.
Bw2--9 to 17 inches; dark yellowish brown (10YR 4/4) gravelly loam; moderate medium subangular blocky structure; friable; many fine roots; 15 percent gravel, 5 percent cobbles, 2 percent stones; strongly acid; clear wavy boundary. (Combined thickness of the Bw horizons is 8 to 28 inches.)
2Cd--17 to 37 inches; yellowish brown (10YR 5/4) very gravelly sandy loam; massive; firm; few 2-3 millimeter wide vertical fractures; common fine roots mainly in fractures; common medium prominent strong brown (7.5YR 5/6) Fe concentrations; 25 percent gravel, 10 percent cobbles, 1 percent stones; moderately acid; abrupt smooth boundary. (5 to 20 inches thick)
3R--37 inches; graywacke bedrock.
TYPE LOCATION: St. Louis County, Minnesota; about 5 miles southwest of the city of Tower; about 225 feet south and 1300 feet west of the northeast corner of sec. 16, T. 61 N., R. 16 W. USGS Lost Lake Quadrangle; latitude 47 degrees 46 minutes 18 seconds N. and longitude 92 degrees 22 minutes 40 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: The depth to bedrock ranges from 20 to 40 inches. The depth to dense till ranges from 15 to 35 inches. Rock fragment content averages 10 to 35 percent, by volume, in the control section.
The A horizon has hue of 10YR, value of 2 or 3, and chroma of 1 or 2. It is loam, silt loam, or fine sandy loam in the fine-earth fraction. Rock fragment content averages 5 to 25 percent by volume with 2 to 10 percent gravel, 0 to 10 percent cobbles, 0 to 10 percent stones and 0 to 5 percent boulders. Reaction is very strongly acid to slightly acid.
The Bw horizon has hue of 10YR or 7.5YR, value of 4 or 5, and chroma of 4 to 6. It is loam, fine sandy loam, or sandy loam in the fine-earth fraction. Rock fragment content averages 5 to 25 percent by volume with 2 to 15 percent gravel, 0 to 10 percent cobbles, 0 to 10 percent stones and 0 to 5 percent boulders. Reaction is very strongly acid to slightly acid.
Some pedons have a BC horizon.
The 2Cd horizon has hue of 2.5Y or 10YR, value of 5 or 6, and chroma of 2 to 4. Texture is sandy loam or coarse sandy loam in the fine earth fraction. Rock fragment content averages 15 to 45 percent by volume with 10 to 35 percent gravel, 5 to 25 percent cobbles, 0 to 10 percent stones and 0 to 5 percent boulders. Reaction is moderately acid to slightly acid. Fractures occur in this horizon.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Wahlsten soils are on linear or convex surfaces of bedrock-controlled uplands. Slopes range from 1 to 8 percent. They formed in a mantle of friable loamy material and dense glacial till over bedrock. The till was deposited by the Rainy Lobe. The bedrock is Precambrian igneous, metamorphic, or sedimentary rocks of the Canadian Shield. Mean annual air temperature is 36 to 40 degrees F. Mean annual precipitation is 27 to 30 inches. Frost-free days range from 90 to 120. Elevation above sea level ranges from 1400 to 1900 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bugcreek, Conic, Eaglesnest, Eveleth, Insula and Quetico soils. Bugcreek soils are very poorly drained. Conic soils are well drained. Eaglesnest and Eveleth soils do not have bedrock above a depth of 80 inches. The well drained Insula soils are shallow to bedrock. The well drained Quetico soils are very shallow to bedrock.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained. Runoff is low to moderately low. Saturated hydraulic conductivity is .01 to 1.41 micrometers per second (.0015 to .20 inches per hour). A perched zone of saturation is at a depth of 2.0 feet from the period from April to June in normal years.
USE AND VEGETATION: Most areas are forested. Principal trees are aspen, paper birch, balsam fir, white spruce, red pine and jack pine. Native vegetation is mixed coniferous and deciduous forest.
DISTRIBUTION AND EXTENT: Northeast Minnesota, MLRA-93. Minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: St Louis County, Minnesota (Virginia subset) 2006.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - the zone from 0 to 3 inches (A horizon); Cambic horizon - the zone from 3 to 17 inches (Bw horizons); Densic contact - the zone from 17 to 37 inches; Lithic contact - 37 inches; Oxyaquic subgroup based on saturation above a depth of 40 inches.
This soil can be challenged for a Spodosol. At the present time there is insufficient lab data to verify a spodic horizon. Lab data will be obtained in the future.
ADDITIONAL DATA: Soil Interpretation Record number MN0822.