LOCATION GERALD MO+KSEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, mesic Aeric Fragiaqualfs
TYPICAL PEDON: Gerald silt loam - on a slope of 2 percent in a cultivated field at an elevation of 1235 feet. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 8 inches; very dark grayish brown (10YR 3/2) silt loam, grayish brown (10YR 5/2) dry; weak fine granular structure; very friable; common fine roots; common worm channels and casts; a few chert gravel; few fine dark manganese concretions; strongly acid; abrupt smooth boundary. (6 to 12 inches thick)
E--8 to 12 inches; grayish brown (10YR 5/2) silt loam; moderate medium and fine platy structure; friable; few fine roots; common worm channels and casts; few chert gravel; common fine dark manganese concretions; strongly acid; abrupt smooth boundary. (3 to 11 inches thick)
Bt1--12 to 16 inches; brown (7.5YR 4/2) silty clay; moderate fine and very fine angular blocky structure; very firm; few fine roots; many prominent dark brown (7.5YR 3/2) clay films on faces of peds; few worm channels and casts; few chert gravel; common medium distinct dark reddish brown (5YR 3/4) masses of iron accumulation; common medium distinct grayish brown (10YR 5/2) silt coats on faces of peds; common fine dark manganese concretions; very strongly acid; clear smooth boundary.
Bt2--16 to 24 inches; dark brown (7.5YR 3/2) clay; moderate and weak coarse prismatic structure parting to moderate medium and coarse angular blocky; very firm; few fine roots; many prominent brown (7.5YR 4/2) clay films on faces of peds; few chert gravel; many medium distinct dark reddish brown (5YR 3/4) masses of iron accumulation; few fine dark manganese concretions; very strongly acid; clear wavy boundary. (Combined thickness of the Bt horizons is 8 to 20 inches.)
2Btx1--24 to 33 inches; light brownish gray (10YR 6/2), yellowish brown (10YR 5/4) and yellowish brown (10YR 5/6) silt loam; weak coarse platy structure; extremely firm; 60 percent brittle; few faint dark gray clay films on faces of peds; 10 percent chert gravel; few fine prominent brown (7.5YR 4/4) masses of iron accumulation; few fine distinct dark gray (10YR 4/1) iron depletions; few fine dark manganese concretions; very strongly acid; gradual wavy boundary.
2Btx2--33 to 44 inches; mottled red (2.5YR 4/6), light brownish gray (10YR 6/2), gray (10YR 6/1) and yellowish red (5YR 4/6) gravelly silty clay loam; weak coarse platy structure; extremely firm; 60 percent brittle; few distinct dark brown and dark gray clay films on faces of peds; 20 percent chert gravel; few fine dark manganese concretions; very strongly acid; clear wavy boundary. (Combined thickness of the 2Btx horizons is 15 to 36 inches.)
2Bt--44 to 72 inches; dark red (2.5YR 3/6) very gravelly clay; moderate fine and medium angular blocky structure; very firm; many distinct dark red clay films on faces of peds; 55 percent chert gravel; common fine distinct gray (10YR 6/1) and light brownish gray (10YR 6/2) iron depletions; few fine dark manganese concretions; very strongly acid.
TYPE LOCATION: Lawrence County, Missouri; about 3 1/2 miles southwest of Mount Vernon; 2,440 feet south and 1,850 feet east of the northwest corner, sec. 4, T. 27 N., R. 27 W; Stotts City, Missouri USGS quadrangle, lat. 37 degrees 0 minutes 53 seconds N. and long. 93 degrees 4 minutes 54 seconds W.
RANGE IN CHARACTERISTICS: Thickness of the solum and depth to bedrock are more than 60 inches. Rock fragment content above the fragipan commonly is less than 5 percent but may range to 15 percent; in the fragipan 5 to 75 percent and below the fragipan 15 to 75 percent.
The Ap or A horizon has hue of 10YR or 7.5YR; value of 2 or 3, 4 or 5 dry; and chroma of 2 or less. It is moderately acid to very strongly acid, and is higher where limed.
The E horizon has hue of 10YR or 7.5YR, value of 4 to 6, and chroma of 2 or less. It is slightly acid to very strongly acid.
The Bt horizon has hue of 10YR to 5YR, value of 2 to 5, chroma of 1 to 4 and is mottled. Low chroma clay films cover the faces of peds where ped interiors have higher chroma. It is silty clay, clay or silty clay loam or their gravelly or cobbly analogues. It is slightly acid or very strongly acid.
The 2Btx has mottled colors of red, gray and brown. It is silt loam or silty clay loam or the gravelly or cobbly analogues. It is typically very strongly acid to moderately acid, but can range as high as slightly alkaline. Some pedons have a 2Ex or 2E horizon immediately above the 2Btx horizon.
The 2Bt horizon has color similar to the fragipan. It is clay, silty clay or silty clay loam or the gravelly and cobbly to extremely gravelly or cobbly analogues. It is very strongly acid to neutral.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Gerald soils are on nearly level uplands and formed in a thin mantle of loess or loamy colluvium over residuum from cherty limestone. Slopes range from 0 to 5 percent. The mean annual temperature ranges from 58 to 62 degrees F, and mean annual precipitation ranges from 37 to 42 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bado, Creldon, Carytown, Eldon, and Keeno soils. Bado soils are on upland depressional areas. Creldon soils commonly are on more sloping positions. Carytown and Eldon soils do not have fragipans. Carytown soils are on depressions and Eldon soils are on more sloping ridgetops. Keeno soils are better drained, have more rock fragments and are on steeper slopes.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Runoff is high to very high. Permeability is very slow. The saturated hydraulic conductivity is low. A seasonal high water table is perched above the fragipan during the winter and early spring in most years.
USE AND VEGETATION: Most areas are cultivated. Native vegetation is tall grasses.
DISTRIBUTION AND EXTENT: The Ozark Highlands (MLRA 116A), the Springfield Plain (MLRA 116B) and the Cherokee Prairie area (MLRA 112) of southern Missouri and southeast Kansas. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Franklin County, Missouri, 1911.
REMARKS: The classification was changed from an Umbric Fragiaqualf to an Aeric Fragiaqualf based on the 1998 Keys to Taxonomy.
Diagnostic horizons and features recognized in this pedon are:
umbric epipedon - the zone from the surface of the soil to a depth of 8 inches (Ap horizon);
albic horizon - the zone from approximately 8 inches to 12 inches (E horizon);
argillic horizon - the zone from approximately 12 to 72 inches or more (Bt1, 2t2, 2Btx1, 2Btx2, and 2Bt horizons);
fragipan - the zone from approximately 24 to 44 inches (2Btx1 and 2Btx2 horizons).