LOCATION GOOD THUNDER MNEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Aquertic Argiudolls
TYPICAL PEDON: Good Thunder silty clay loam with on a 2 percent slope in a cultivated field. (Colors are for moist soils unless otherwise indicated.)
Ap--0 to 7 inches; black (10YR 2/1) silty clay loam, dark gray (10YR 4/1) dry; weak medium and fine subangular blocky structure; friable; slightly acid; abrupt smooth boundary.
A--7 to 15 inches; black (10YR 2/1) silty clay loam, very dark gray (10YR 3/1) and dark gray (10YR 4/1) dry; moderate medium and fine angular blocky structure; friable; moderately acid; clear wavy boundary. (Combined thickness of the A horizon ranges from 8 to 18 inches)
Bt1--15 to 21 inches; very dark grayish brown (10YR 3/2) silty clay; light brownish gray (2.5Y 6/2) and light gray (2.5Y 7/2) (dry) ped exteriors; moderate medium and coarse prismatic parting to moderate medium angular blocky structure; firm; few faint very dark brown (10YR 2/2) clay films on faces of peds and in pores; moderately acid; clear wavy boundary.
Bt2--21 to 32 inches; dark grayish brown (10YR 4/2) silty clay; moderate coarse prismatic structure parting to fine and medium angular blocky; firm; common distinct very dark grayish brown (2.5Y 3/2) clay films on faces of peds and in pores; strongly acid; clear wavy boundary.
Bt3--32 to 37 inches; light olive brown (2.5Y 5/3) silty clay loam moderate coarse prismatic structure; firm; common distinct black (10YR 2/1) clay films on faces of peds and root channels; many fine distinct light olive brown (2.5Y 5/6) Fe concentrations; slightly acid; gradual wavy boundary. (Combined thickness of the Bt horizons is 18 to 38 inches)
C1--37 to 64 inches; yellow (10YR 7/6) silt loam; friable; few organic stains in root channels; weak fine platy varves; strongly effervescent; slightly alkaline; abrupt wavy boundary.
C2--64 to 80 inches; light yellowish brown (2.5Y 6/4) silt loam; friable; weak fine platy varves; strongly effervescent; slightly alkaline.
TYPE LOCATION: Blue Earth County, Minnesota; about 1 mile west of Good Thunder; 2650 feet west and 2300 feet south of the northeast corner of Sec. 8, T. 106 N., R. 27 W.; USGS Good Thunder quadrangle: latitude 44 degrees 00 minutes 05 seconds N. and longitude 94 degrees 05 minutes 58 seconds W.; NAD27.
RANGE IN CHARACTERISTICS: The depth to free carbonates ranges from 28 to 50 inches. The mollic epipedon ranges from 8 to 22 inches thick and may include the upper part of the B horizon. The sand content is less than 15 percent in the series control section. Rock fragments are typically not present in the profile.
The Ap or A horizon has a hue of 10YR, value of 2 or 3, chroma of 1 or 2. It is silty clay loam or silty clay. Reaction is moderately acid to neutral. Some pedons have an E horizon.
The Bt horizons have hues of 10YR or 2.5Y, value of 3 to 6, and a chroma of 2 to 4. The upper 20 inches of the Bt horizon averages between 35 and 50 percent clay. B/A clay ratios range from 1.2 to 1.4. It is silty clay or silty clay loam. It is strongly acid to neutral.
Some pedons have a Bk horizon.
The C horizon has a hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 2 to 8. It silt loam or silty clay loam. Reaction is slightly alkaline or moderately alkaline. The horizon typically has fine varves of very fine sandy loam or loamy very fine sandy loam 1 to 2 mm thick. The CaCO3 content is typically 10 to 20 percent.
COMPETING SERIES: These are the Adair, Arisburg, Arispe, Chase, Greenton, Grundy, Lagonda, Lamoni, Mahaska, Martin, Maybery, Pawnee, Rutland, Seymour, Shorewood, Tina and Wymore soils. The Adair, Lamoni, Mayberry, and Shorewood soils have glacial till or reworked glacial till in the lower third of the series control section with more than 15 percent sand content. The Arisburg, Arispe, Grundy, Mahaska, Seymour and Tina soils do not have free carbonates above a depth of 50 inches. Chase soils have a mollic epipedon greater than 36 inches in thickness. The Greenton, Martin and Rutland soils have clay or silty clay textures in the C horizon. The Lagonda soils have a lithologic discontinuity of loess over till derived sediment in the control section. Wymore soils formed in deep loess and typically have less than 10 percent CaCO3 equivalent in the lower third of the series control section.
Adair, Lagonda, Lamoni and Shorewood soils have a 2C horizon or C horizon of glacial till with rock fragments. Arisburg, Arispe, Grundy, Mahaska, Seymour and Tina soils do not have free carbonates in the lower third of the series control section. Chase soils have mollic epipedons that are over 36 inches thick. Greenton soils formed in loess with underlying material of residuum from shale and thinly bedded limestone. Martin soils have a mollic epipedon greater than 24 inches thick. Mayberry soils have hues of 7.5YR and 5YR in the upper Bt horizon. Rutland soils have a lithologic discontinuity at the contact of the loess and clayey glacial till or lacustrine sediments. Wymore soils have an argillic horizon that starts at depths of less than 15 inches.
GEOGRAPHIC SETTING: Good Thunder soils have plane or convex slopes on glacial lake plains. Slopes range from 0 to 6 percent. They formed in lacustrine materials of Wisconsin age. Mean annual air temperature ranges from 45 to 50 degrees F. Mean annual precipitation ranges from 25 to 32 inches. Frost-free days range from 124 to 165. Elevation above sea level ranges from 900 to 1200 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Minnetonka, Barbert, and Lura soils which are members of a hydrosequence with Good Thunder soils. The poorly drained Minnetonka soils are on lower positions in the landscape. The Barbert and Lura soils are very poorly drained and are in depressions.
DRAINAGE AND PERMEABILITY: Moderately well drained. Permeability is moderately slow or slow in the upper part, and moderately slow or moderate in the lower part. Surface runoff is low on lesser slopes and medium on steeper slopes. A perched water table is 2.5 to 3.5 feet from April to June in normal years.
USE AND VEGETATION: Most areas of these soils are cultivated. Corn and soybeans, are the principal crops, although some hay is grown. Native vegetation is mixed tall grass prairie and hardwoods.
DISTRIBUTION AND EXTENT: South central and southeastern Minnesota. These soils are of minor extent in MLRA-103.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES PROPOSED: Waseca County, Minnesota, 6/2000. The name is from a small town in the Blue Earth County, Minnesota.
REMARKS: In 1975 this soil was correlated as Shorewood silty substratum in Blue Earth County, Minnesota. Diagnostic horizons and features recognized in this pedon are: mollic epipedon - 0 to 15 inches (Ap); argillic horizon - 15 to 32 inches (Bt1, Bt2 and Bt3 horizons); aquertic subgroup-a LE of 6.0 cm or more from the surface to 100 cm.
ADDITIONAL DATA: Refer to MAES central file code no.3785 for this pedon, and 1604, 6089, 6090, and 3853 for results of laboratory analysis of similar pedons.