LOCATION OSKA KS+MOEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Argiudolls
TYPICAL PEDON: Oska silty clay loam, 4 percent slopes in pastureland. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 13 centimeters; dark brown (7.5YR 3/2) silty clay loam, brown (7.5YR 4/2) dry; moderate medium subangular blocky structure parting to moderate fine granular; slightly hard friable, slightly sticky and slightly plastic; many very fine and fine roots throughout; moderately acid; abrupt smooth boundary.
BA--13 to 28 centimeters; dark brown (7.5YR 3/2) silty clay, brown (7.5YR 4/2) dry; moderate medium subangular blocky structure parting to moderate fine granular; slightly hard friable, slightly sticky and slightly plastic; many very fine and fine roots throughout; moderately acid; clear smooth boundary. (15 to 25 centimeters thick)
Bt1--28 to 51 centimeters; dark brown (7.5YR 3/4) silty clay, brown (7.5YR 4/4) dry; moderate medium subangular blocky structure parting to moderate fine subangular blocky; very hard firm, very sticky and very plastic; many very fine and fine roots throughout; common very fine tubular pores; few faint discontinuous dark brown (7.5YR 3/3) clay films on faces of peds; 3 percent subangular mixed gravel; moderately acid; clear smooth boundary.
Bt2--51 to 79 centimeters; dark reddish brown (5YR 3/4) silty clay, reddish brown (5YR 4/4) dry; strong medium subangular blocky structure parting to strong fine subangular blocky; very hard firm, very sticky and very plastic; many very fine and fine roots throughout; many very fine tubular pores; many distinct discontinuous dark reddish brown (5YR 3/3) clay films throughout and few prominent discontinuous dark reddish brown (5YR 3/2) organic coats on faces of peds; common fine rounded black (N 2/0) slightly hard iron-manganese concretions between peds; 3 percent subangular mixed gravel and 3 percent subangular mixed cobbles; strongly acid; gradual wavy boundary.
Bt3--79 to 97 centimeters; dark reddish brown (5YR 3/4) silty clay, reddish brown (5YR 4/4) dry; strong medium subangular blocky structure parting to strong fine subangular blocky; very hard firm, very sticky and very plastic; many very fine and fine roots throughout; many very fine tubular pores; many distinct discontinuous dark reddish brown (5YR 3/3) clay films throughout and few prominent discontinuous dark reddish brown (5YR 3/2) organic coats on faces of peds; common fine rounded black (N 2/0) slightly hard iron-manganese concretions between peds; 3 percent subangular mixed gravel and 3 percent subangular mixed cobbles; moderately acid; gradual wavy boundary. (Combined thickness of the Bt horizon is 25 to 81 centimeters thick)
R--97 centimeters; Limestone bedrock
TYPE LOCATION: Douglas County, Kansas; about 1.5 miles south and 4.25 miles west of Lawrence; 274 meters (900 feet) south and 792 meters (2600 feet) west of the northeast corner of sec. 30, T. 13 S., R. 19 E.; USGS Lawrence West quad; lat. 38 degrees 53 minutes 46 seconds N. and long. 95 degrees 20 minutes 37 seconds W.
RANGE IN CHARACTERISTICS:
Mollic epipedon: 20 to 51 centimeters
Depth to lithic contact: 51 to 102 centimeters to bedrock
Depth to argillic horizon: 25 to 38 centimeters
Particle-size control section (weighted average): 41 percent
Clay content: 35 to 60 percent
Sand content: 0 to 10 percent
A horizon:
Hue: 10YR or 7.5YR
Value: 2 or 3, 4 or 5 dry
Chroma: 1 to 3
Texture: silty clay loam and silt loam
Clay content: 20 to 35 percent
Reaction: strongly acid to neutral
BA horizon:
Hue: 10YR, 7.5YR
Value: 2 or 3, 4 or 5 dry
Chroma: 2 or 3
Texture: silty clay loam or silty clay
Clay content: 20 to 50 percent
Reaction: strongly acid to neutral
Bt horizons:
Hue: 7.5YR or 5YR
Value: 3 to 5, 4 to 6 dry
Chroma: 2 to 6
Texture: silty clay or silty clay loam
Clay content: 35 to 60 percent
Reaction: strongly acid to neutral
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Parent material: Residuum derived from limestone and shale.
Landform: nearly level to sloping uplands
Slopes: 1 to 9 percent
Mean annual temperature: 10 to 12 degrees C. (50 to 54 degrees F.)
Mean annual precipitation: 86 to 102 centimeters
Frost-free period: 170 to 190 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Bendena,
Martin,
Morrill,
Pawnee,
Polo, and
Vinland series.
The Bendena, Martin, and Vinland soils are on slopes below Oska soils.
The Martin, Morrill, and Pawnee soils are greater than 102 centimeters to lithic contact.
Pawnee and Polo soils are on higher landscapes than Oska soils. Bendena, and Vinland soils have bedrock at depths less than 51 centimeters.
Morrill soils are on similar landscapes as Oska soils.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: Well drained
Saturated hydraulic conductivity: moderately low
USE AND VEGETATION: About half of the acreage is cultivated.
Sorghum, soybeans, wheat, and alfalfa are the principal crops.
The remainder is range or pasture.
Native vegetation is tall and midgrasses.
DISTRIBUTION AND EXTENT: Northeastern Kansas, Northwestern Missouri; MLRA 106; moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Leavenworth and Wyandotte Counties, Kansas, 1973.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: 28 to 78 centimeters (Bt1 and Bt2 horizons)
Mollic epipedon: 0 to 28 centimeters (Ap and A horizons)
Argillic horizon: 28 to 97 centimeters (Bt1, Bt2, and Bt3 horizons)
Lithic contact: The contact with limestone at 97 centimeters (R horizon)
Pedon used is 94KS045004. Lab data was run at the National Soil Survey Laboratory in Lincoln, Nebraska. Lab samples were 94P6360-6364.
Modified format by LRM in 7/2006
09/2008 GJJ added some metric conversions, and removed English units.
11/2008 JCR Increased clay range of Bt from 50 to 60 percent based on soil characterization data.