LOCATION LITTLESWAN MNEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Aquollic Hapludalfs
TYPICAL PEDON: Littleswan silt loam on a slightly concave slope of 2 percent, in a wooded area, at an elevation of 1280 feet. (Colors are for moist soil unless otherwise stated.)
A--0 to 4 inches; very dark brown (10YR 2/2) silt loam, grayish brown (10YR 5/2) dry; weak medium granular structure; friable; moderately acid; clear smooth boundary. (3 to 9 inches thick)
E--4 to 8 inches; gray (2.5Y 5/1) silt loam, light gray (2.5Y 7/1) dry; moderate coarse angular blocky parting to moderate medium platy structure; friable; moderately acid; clear wavy boundary. (2 to 7 inches thick)
Bt1--8 to 19 inches; grayish brown (2.5Y 5/2) silty clay loam; moderate medium subangular blocky structure; friable; many faint dark gray (2.5Y 4/1) clay films on faces of peds; common fine distinct light olive brown (2.5Y 5/4) iron concentrations; slightly acid; gradual wavy boundary.
Bt2--19 to 25 inches; light yellowish brown (2.5Y 6/3) silty clay loam; moderate coarse subangular blocky parting to moderate medium subangular blocky structure; friable; common distinct gray (2.5Y 5/1) clay films on faces of peds; common medium prominent dark yellowish brown (10YR 4/6) iron concentrations; slightly acid; abrupt wavy boundary. (Combined thickness of the Bt horizons is 8 to 24 inches.)
Btg--25 to 38 inches; grayish brown (2.5Y 5/2) silty clay loam; weak coarse subangular blocky structure; friable; common faint gray (2.5Y 5/1) clay films on faces of peds; common medium prominent strong brown (7.5YR 5/6) iron concentrations; common medium faint light gray (2.5Y 7/2) iron depletions; neutral; gradual wavy boundary. (0 to 20 inches thick.)
Cg1--38 to 70 inches; olive gray (5Y 5/2) silt loam; massive; friable; few fine faint light gray (5Y 7/1) rounded masses of carbonate accumulation; common medium prominent strong brown (7.5YR 5/6) iron concentrations; few fine faint gray (5Y 6/1) iron depletions; slight effervescence; slightly alkaline; gradual wavy boundary.
Cg2--70 to 80 inches; olive gray (5Y 5/2) silt loam; massive; friable; few fine distinct white (5Y 8/1) rounded masses of carbonate accumulation; common fine prominent dark yellowish brown (10YR 4/6) iron concentrations; slight effervescence; slightly alkaline.
TYPE LOCATION: St. Louis County, Minnesota; about 17 miles south of Buhl; 200 feet north and 100 feet east of the southwest corner of Section 8, T. 55 N., R. 19 W., USGS Little Swan, Minnesota Quadrangle; latitude 47 degrees 15 minutes 17 seconds N. and longitude 92 degrees 47 minutes and 20 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: The series control section does not have rock fragments. Depth to free calcium carbonate ranges from 24 to 40 inches. The series control section has more than 50 percent very fine sand or finer.
Some pedons have an Oe or Oa horizon as much as 4 inches thick.
The A horizon has hue of 10YR, value of 2 or 3 and chroma of 1 or 2. Texture is silt loam, loam or very fine sandy loam. Reaction is moderately acid to neutral. Some pedons have an Ap horizon as much as 10 inches thick.
The E horizon has hue of 2.5Y or 10YR, value of 4 or 5 and chroma of 1 or 2. Texture is silt loam, loam or very fine sandy loam. Reaction is moderately acid to neutral.
The Bt horizon has hue of 2.5Y or 10YR, value of 4 to 6 and chroma of 2 or 3. Texture is silty clay loam or silt loam. Reaction is slightly acid to neutral.
The Btg horizon has hue of 2.5Y or 10YR, value of 4 or 5 and chroma of 2. Texture is silty clay loam or silt loam. Reaction is slightly acid to slightly alkaline.
The BC horizon, where present, has hue of 2.5Y or 10YR, value of 4 to 6 and chroma of 2 or 3. Texture is silt loam, silty clay loam, loam or very fine sandy loam. Loamy very fine sand, silt, clay loam or sandy loam may occur as thin strata. Reaction is slightly acid to moderately alkaline.
The Btk or Bk horizons, where present, have hue of 10YR to 5Y, value of 4 to 6 and chroma of 1 to 4. Texture is silt loam, silty clay loam, loam or very fine sandy loam. Loamy very fine sand, silt, clay loam or sandy loam may occur as thin strata. Reaction is neutral to moderately alkaline.
The Cg horizon has hue of 10YR to 5Y, value of 4 to 6 and chroma of 1 to 3. Texture is silt loam, silty clay loam, loam or very fine sandy loam. Loamy very fine sand, silt, clay loam, or sandy loam may occur as thin strata. Reaction is neutral to moderately alkaline.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Littleswan soils are on slightly concave to convex surfaces of glacial lake plains. Slopes range from 1 to 4 percent. They formed in silty glaciolacustrine materials. Mean annual air temperature is 38 to 40 degrees F. Mean annual precipitation is 26 to 28 inches. The frost-free period is 95 to 125 days. Elevation above sea level is 1250 to 1370 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Baudette and Spooner soils. The moderately well drained Baudette and poorly drained Spooner soils form a hydrosequence with the Littleswan soils.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Runoff is low to medium. Saturated hydraulic conductivity is moderate. Littleswan soils have seasonal high saturation at 1 foot at some time from April through June and October through November in normal years.
USE AND VEGETATION: Most areas are forested. Principal trees are aspen, balsam fir, white spruce, black spruce, and jack pine. Some areas are used for hayland or pastureland. Native vegetation is mixed coniferous and deciduous forest.
DISTRIBUTION AND EXTENT: Northeastern Minnesota, MLRA-88. Small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota.
SERIES ESTABLISHED: St. Louis County, Minnesota 2005.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - the zone from 0 to 8 inches (A and E horizons); Albic horizon - the zone from 4 to 8 inches (E horizon); Argillic horizon - the zone from 8 to 38 inches (Bt horizons); Aquic subgroup based on 2 chroma iron depletions in the upper 10 inches of the argillic horizon and aquic conditions for some time in normal years.