LOCATION BIG IRON MIEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aquic Glossudalfs
TYPICAL PEDON: Big Iron silt loam, on a one percent north-facing slope in a forested area at an elevation of 223 meters. (Colors are for moist soil unless otherwise stated.)
Oi--0 to 2 centimeters; slightly decomposed hardwood loose leaf litter and twigs; strongly acid.
A--2 to 8 centimeters; black (7.5YR 2.5/1) silt loam, very dark gray (10YR 3/1) dry; moderate medium granular structure; friable; many very fine to coarse roots; about 1 percent gravel; very strongly acid; abrupt smooth boundary. (0 to 20 centimeters thick)
E--8 to 10 centimeters; brown (7.5YR 5/3) silt loam, light brown (7.5YR 6/3) dry; moderate fine and medium subangular blocky structure; friable; common very fine to coarse roots; about 2 percent gravel; very strongly acid; clear broken boundary. (0 to 30 centimeters thick)
Bw--10 to 28 centimeters; brown (7.5YR 4/4) loam; moderate medium subangular blocky structure; friable; common very fine to coarse roots; few medium prominent yellowish red (5YR 5/6) masses of iron accumulation; about 3 percent gravel; very strongly acid; clear wavy boundary. (13 to 25 centimeters thick)
E/B--28 to 43 centimeters; brown (7.5YR 5/3) loam (E), pinkish gray (7.5YR 7/2) dry; occupies about 70 percent of the horizon surrounding isolated remnants of reddish brown (5YR 4/4) silt loam (B); weak thick platy structure; firm; few very fine to coarse roots; common medium prominent yellowish red (5YR 5/8) masses of iron accumulation; about 6 percent gravel; very strongly acid; clear wavy boundary. (Glossic horizon is 13 to 38 centimeters thick)
Bt--43 to 119 centimeters; reddish brown (2.5YR 4/4) silt loam; weak very thick platy structure; firm; few fine and medium roots between peds; many distinct red (2.5YR 4/6) clay films on faces of peds; common medium prominent yellowish red (5YR 5/6) masses of iron accumulation; few coarse prominent brown (7.5YR 4/2) iron depletions; about 5 percent gravel; neutral; gradual wavy boundary.
BCd1--119 to 168 centimeters; reddish brown (2.5YR 4/4) loam; weak coarse subangular blocky structure; firm; few distinct red (2.5YR 4/6) clay films on faces of peds; few distinct red (2.5YR 4/6) sand coats on faces of peds; about 10 percent gravel; slightly alkaline; gradual wavy boundary. (23 to 51 centimeters thick)
BCd2--168 to 203 centimeters; reddish brown (2.5YR 4/4) gravelly silt loam; weak coarse angular blocky structure; firm; about 30 percent gravel; neutral.
TYPE LOCATION: Major Land Resource Area (MLRA 92) Superior Lake Plain, Ontonagon County Michigan Subset; about 3.5 miles southeast of Silver City; 2300 feet north and 150 feet west of the southeast corner of Section 15, T51N, R42W, USGS White Pine, MI, topographic quadrangle.; lat. 46 degrees 49 minutes 24 seconds N. and long. 89 degrees 30 minutes 4 seconds W., NAD 1927.
RANGE IN CHARACTERISTICS:
Depth to the densic layer (physically root restrictive): 102 to 152 centimeters
Gravel content (A, E, Bw, E/B, Bt horizons): 0 to 10 percent
Gravel content (BCd horizon): 0 to 30 percent
Cobble content - 0 to 5 percent throughout
Reaction (A, E, Bw, and E/B horizons): very strongly acid to moderately acid Reaction (Bt and BCd horizons): strongly acid to strongly alkaline.
Some pedons have free carbonates below 152 centimeters.
A horizon
Hue: 5YR or 7.5YR
Value: 2 or 3
Chroma: 1 or 2
Texture: silt loam, loam or fine sandy loam
E horizon
Hue: 5YR or 7.5YR
Value: 4 or 5
Chroma: 2 or 3
Texture: silt loam, loam or fine sandy loam
Bw horizon
Hue: 5YR or 7.5YR
Value: 3 or 4
Chroma: 3 or 4
Texture: loam, silt loam or fine sandy loam
E part of the E/B and B/E horizons
Hue: 5YR or 7.5YR
Value: 4 to 7
Chroma: 2 or 3
Texture: fine sandy loam, loam or silt loam
B part of the E/B and B/E horizons
Hue: 2.5YR, 5YR or 7.5YR
Value: 4 or 5
Chroma: 3 to 6
Texture: loam, silt loam or fine sandy loam
Bt horizon
Hue: 2.5YR or 5YR
Value: 4 or 5
Chroma: 3 or 4
Texture: silt loam, loam, or clay loam
BCd horizon
Hue: 2.5YR or 5YR
Value: 3 to 5
Chroma: 3 to 6
Texture: silt loam, loam or gravelly analogs
Some pedons have a C horizon
Hue: 2.5YR or 5YR
Value: 3 to 5
Chroma: 4 to 6
Texture: loam, silt loam or gravelly, very gravelly or cobbly analogs
COMPETING SERIES: These are the
Alstad,
Dusler,
Keewatin,
Kert,
Meadland,
Milladore,
Nary,
Point,
Rietbrock and
Withee soils.
Alstad - do not have a densic layer at 102 to 152 centimeters and have 15 to 30 percent medium, coarse or very course sand in the series control section.
Dusler, Meadland, Milladore, Point and Withee - do not have a densic layer at depths of 102 to 152 centimeters
Keewatin - have hues of 2.5Y and 10YR and Ex horizons
Kert - have a paralithic contact within a depth of 51 to 102 centimeters
Nary have hues of 2.5Y and 10YR and are water saturated at depths of 76 to 107 centimeters from April to June in years with normal precipitation
Rietbrock - have a lithic contact at depths of 102 to 152 centimeters
GEOGRAPHIC SETTING:
Parent material - poorly-mixed basal till derived from local siltstone and sandstone bedrock
Landform - ground moraines
Slope - 0 to 8 percent
Mean annual precipitation - 790 to 860 millimeters
Mean annual air temperature - 4 to 7 degrees C.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Belding,
Flintsteel,
Gull Point,
Loggerhead, and
Watton soils.
Members of the typical drainage sequence (catena) include Flintsteel and Watton.
Belding - are on similar landscape positions but are in the Alfic Epiaquods Subgroup
Flintsteel - are on higher or steeper landscape positions and in the Oxyaquic Glossudalfs Subgroup
Gull Point - are in drainageways and in the Typic Argiaquolls Subgroup
Loggerhead - are on slightly higher landscape positions and in the Alfic Oxyaquic Haplorthods Subgroup
Watton - are on higher or steeper landscape positions and in the Haplic Glossudalfs Subgroup
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage a perched seasonal zone of water saturation exists 15 to 61 centimeters below the surface from October to May (somewhat poorly drained). Surface runoff - low to medium depending on slope.
Saturated hydraulic conductivity - moderate in the A, E, Bw, and E/B, horizons; moderately slow in the Bt horizon; and very slow in the BCd horizon.
USE AND VEGETATION: Most areas are forested. The major species are sugar maple, red maple, green ash, quaking aspen, eastern hemlock, basswood, yellow birch, white spruce and balsam fir. Some areas are used for pasture and hay production or are idle.
DISTRIBUTION AND EXTENT:
Physiographic Division
--Laurentian Upland
Physiographic Province
--Superior Upland
Land Resource Region
--Northern Lake States Forest and Forage region (LRR K)
Major Land Resource Area
--Superior Lake Plain (MLRA 92)
--Superior Stony and Rocky Loamy Plains and Hills, Eastern Part (MLRA 93B)
The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Major Land Resource Area 92 Superior Lake Plain; Ontonagon County Michigan Subset, January 2007. Proposed in Ontonagon County, Michigan, 2001. The source of the name is the Big Iron River in Ontonagon County.
REMARKS: Diagnostic horizons and features in the typical pedon include:
Ochric epipedon - 0 to 10 centimeters (Oi, A and E horizons)
Glossic horizon - 28 to 43 centimeters (E/B horizon)
Argillic horizon - 43 to 119 centimeters (Bt horizon)
Densic layer contact - 119 centimeters
Aquic feature - redox depletions with chroma of 2 below 43 centimeters
ADDITIONAL DATA: Refer to lab sample number S99MI-131-004 for Primary Characterization Data from NSSL, Lincoln, NE.