LOCATION GOODSON MOEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, mesic Oxyaquic Hapludalfs
TYPICAL PEDON: Goodson gravelly silt loam on a south-facing, convex, 6 percent slope in pasture at an elevation of 1,075 feet. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 9 inches; very dark grayish brown (10YR 3/2) gravelly silt loam, grayish brown (10YR 5/2) dry; moderate fine granular structure; friable; many fine roots; 20 percent subrounded chert gravel; slightly acid; clear smooth boundary. (6 to 9 inches thick.)
Bt1--9 to 15 inches; brown (10YR 4/3) silty clay loam; common fine distinct dark yellowish brown (10YR 4/4) and few fine prominent yellowish red (5YR 4/6) lithic-chromic mottles; moderate very fine subangular blocky structure; firm; many fine roots; many distinct clay films on faces of peds; 5 percent subrounded chert gravel; strongly acid; gradual smooth boundary. (5 to 10 inches thick.)
2Bt2--15 to 22 inches; brown (7.5YR 5/4) clay, common fine distinct strong brown (7.5YR 4/6) and few fine prominent yellowish red (5YR 4/6) lithic-chromic mottles; moderate very fine subangular blocky structure; firm; many fine roots; many distinct clay films on faces of peds; 5 percent subrounded chert gravel; very strongly acid; gradual smooth boundary.
2Bt3--22 to 32 inches; brownish yellow (10YR 6/6) silty clay; few fine distinct dark yellowish brown (10YR 4/6) lithic-chromic mottles; strong fine subangular blocky structure; very firm; common fine roots; common distinct clay films on faces of peds; 5 percent subrounded chert gravel; moderately acid; gradual smooth boundary. (Combined thickness of the 2Bt is 15 to 25 inches.)
3Bt4--32 to 37 inches; brownish yellow (10YR 6/6) and gray (10YR 6/1) silty clay loam; strong medium subangular blocky structure; very firm; few fine roots; common distinct clay films on faces of peds; 10 percent siltstone channers; slightly alkaline; clear wavy boundary.
3Bt5--37 to 44 inches; light olive gray (5Y 6/2) silty clay loam; medium coarse subangular blocky structure; firm; few fine roots; common faint clay films on faces of peds; many medium distinct olive yellow (2.5Y 6/6) masses of iron accumulation in ped interiors; moderately alkaline; gradual smooth boundary. (Combined thickness of the 3Bt is 12 to 31 inches)
3Cr--44 to 54 inches; shale-siltstone
TYPE LOCATION: Polk County, Missouri; about 2 miles north of Huron, Missouri; 2050 feet west and 350 feet north of the southeast corner of sec. 33, T. 35N., R. 22W.; USGS Polk quadrangle; latitude 37 degrees 44 minutes 6 seconds N. and longitude 93 degrees 21 minutes 55 seconds W..
RANGE IN CHARACTERISTICS:
The mean annual soil temperature at 20 inches is 56 to 59 degrees F.
Depth to a paralithic contact and to the base of the argillic horizon is 40 to 60 inches.
A horizon:
Value: 2 or 3 moist and 3, 4 or 5 dry
Chroma: 1 to 3
Fine-earth: silt loam or silty clay loam
Rock fragments: 5 to 35 percent gravel
Reaction: neutral to strongly acid
BA and Bt horizons:
Value: 4 or 5
Chroma: 3 or 4
Fine-earth: silt loam, or silty clay loam
Rock fragments: 0 to 30 percent gravel
Reaction: neutral to strongly acid
2Bt horizon:
Hue: 2.5YR to 5YR
Value: 4 to 6
Chroma: 3 to 8
Mottles: Hue 2.5YR to 10YR: Value 4 to 6: Chroma 3 to 8
Fine-earth: silty clay or clay
Rock fragments: 0 to 10 percent gravel
Reaction: slightly acid to very strongly acid
3Bt horizon:
Matrix colors in the lower argillic are variable due to the litho-chromic influence of the shale parent material.
Redoximorphic features
Hue: 2.5YR to 2.5Y
Value: 4 to 6
Chroma: 4 to 8
Fine-earth: silty clay loam, silty clay or clay
Rock fragments: 0 to 20 percent channers
Reaction: moderately alkaline to neutral
COMPETING SERIES: These are the Alsup, Losantville, Miamian, Morrisville, Shircliff, Skrainka, and Useful series. Alsup soils do not have mollic colors in the surface layer. Losantville soils have free carbonates at a depth of 8 to 20 inches and are more than 60 inches to a paralithic contact. Miamian soils are more than 60 inches to a paralithic contact and have free carbonates from 18 to 40 inches. Morrisville soils have a lithic contact at 40 to 60 inches and free carbonates in the lower part of the series control section. Shircliff soils are more than 60 inches to a paralithic contact and have free carbonates from 30 to 60 inches. Skrainka soils do not have mollic colors in the surface layer and are more than 60 inches to a paralithic contact. Useful soils have a lithic contact at 40 to 60 inches.
GEOGRAPHIC SETTING: These soils are on upland ridgetops and side slopes. Slope ranges from 1 to 15 percent. The soils formed in colliuvium or loess and the underlying residuum from shale or interbedded shale and siltstone. Chert fragments are commonly a part of the colluvium. Mean annual temperature ranges from 55 to 58 degrees, and mean annual precipitation ranges from 40 to 46 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alsup, Bona, Creldon, Hoberg, Ocie and Viraton soils. Bona soils are clayey-skeletal, are very deep to a lithic or paralithic contact and are on ridgetops and side slopes above the Goodson soils. Alsup soils have a light colored surface layer and are on similar positions to the Goodson soils. Creldon and Hoberg soils have a fragipan and are on more level areas above the Goodson soils. Ocie soils are loamy-skeletal over clayey and are on side slopes below the Goodson soils. Viraton soils are fine-loamy, have a fragipan and are below the Goodson soils on broad level areas.
DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff is medium to high. Permeability is moderately slow. In undisturbed areas, a perched water table has an upper limit of 2.5 to 4.0 feet during December to March in most years.
USE AND VEGETATION: Most areas are in grasses and legumes. Some small grain crops are grown on the more gentle slopes. Native vegetation is tall grasses.
DISTRIBUTION AND EXTENT: Ozark Border area (MLRA 116B) of southwest Missouri. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Little Rock, Arkansas
SERIES ESTABLISHED: Polk County, Missouri, 1995.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon - the zone from the surface of the soil to a depth of 9 inches (Ap horizon).
Argillic horizon - the zone from a depth of 9 inches to 44 inches (Bt, 2Bt abd 3Bt horizons).
Paralithic contact - soft shale-siltstone at 44 to 51 inches (2Cr horizon).
In southwestern Missouri, these soils formed in materials weathered exclusively from shales and siltstones from the Northview formation.
ADDITIONAL DATA: University of Missouri Soil Characterization Laboratory reference number M9016774; Polk County pedon number 89MO167074.
Interpretations for the typical pedon are stored in the Missouri NASIS data set in DMU description 167 70017.