LOCATION PAWNEE NE+KS
Established Series
Rev. SAS, JCR, DJK
11/2010
PAWNEE SERIES
The Pawnee series consists of very deep, moderately well drained soils that formed in till. Pawnee soils are on hillslopes of dissected till plains in Nebraska and Kansas Loess-Drift Hills, MLRA 106. Slopes range from 0 to 12 percent. Mean annual precipitation is about 864 millimeters (34 inches) and the mean annual temperature is about 12 degrees C (54 degrees F).
TAXONOMIC CLASS: Fine, smectitic, mesic Oxyaquic Vertic Argiudolls
TYPICAL PEDON: Pawnee loam on a west-facing, 6 percent slope in a cultivated field at an elevation of 372 meters (1220 feet). (Colors are for moist soil unless otherwise stated.)
Ap--0 to 15 centimeters; very dark brown (10YR 2/2) loam, dark grayish brown (10YR 4/2) dry; moderate fine and very fine granular structure; many fine and medium and few coarse roots throughout; common fine tubular pores; slightly hard, friable; moderately acid; abrupt smooth boundary. (10 to 18 centimeters thick)
A--15 to 25 centimeters; very dark brown (10YR 2/2) clay loam, very dark grayish brown (10YR 3/2) dry; moderate medium granular structure; many fine and medium and few coarse roots throughout; common fine tubular pores; slightly hard, friable; moderately acid; clear smooth boundary. (8 to 15 centimeters thick)
BA--25 to 36 centimeters; dark brown (10YR 3/3) clay loam, dark yellowish brown (10YR 3/4) dry; moderate fine and medium blocky structure; hard, friable; common fine and few medium roots throughout; common fine tubular pores; few fine prominent dark reddish brown (5YR 3/4) iron masses; moderately acid; gradual smooth boundary. (0 to 15 centimeters thick)
Bt1--36 to 61 centimeters; dark grayish brown (10YR 4/2) clay, brown (10YR 4/3) dry; moderate medium and coarse blocky structure; extremely hard, very firm; common fine and few medium roots throughout; common fine tubular pores; thin continuous organic coatings on faces of peds; 2 percent gravel by volume; few fine and medium prominent reddish brown (5YR 4/4) iron masses; slightly acid; gradual smooth boundary.
Bt2--61 to 81 centimeters; brown (10YR 4/3) clay, dark yellowish brown (10YR 4/4) dry; weak coarse blocky structure; extremely hard, very firm; few fine and medium roots throughout; few fine tubular pores; thin continuous organic coatings on faces of peds; 2 percent gravel by volume; common medium faint grayish brown (10YR 5/2), strong brown (7.5YR 5/6) and prominent reddish brown (5YR 5/4) iron masses; neutral; gradual smooth boundary.
Bt3--81 to 114 centimeters; olive brown (2.5Y 4/4) clay, light olive brown (2.5Y 5/4) dry; weak coarse blocky structure; very hard, very firm; few fine and medium roots throughout; few fine tubular pores; thin patchy organic coatings on faces of peds; 2 percent gravel by volume; many medium distinct grayish brown (10YR 5/2) and prominent brown (7.5YR 5/4) iron masses; moderately alkaline; gradual smooth boundary. (Combined thickness of the Bt horizons is 56 to 89 centimeters thick)
BC--114 to 135 centimeters; mixed grayish brown (2.5Y 5/2) and yellowish brown (10YR 5/6) clay, light olive brown (2.5Y 5/4) and dark yellowish brown (10YR 4/4) dry; weak medium blocky structure; very hard, very firm; few fine and medium roots throughout; few fine tubular pores; few medium lime concretions; 2 percent gravel by volume; many medium prominent brown (7.5YR 4/4) iron masses; moderately alkaline; clear smooth boundary. (20 to 25 centimeters thick)
C--135 to 203 centimeters; grayish brown (2.5Y 5/2) clay loam, light olive brown (2.5Y 5/4) dry; massive; small iron and manganese concretions; 2 percent gravel by volume; few medium and large soft masses of lime; many coarse distinct grayish brown (10YR 5/2) iron masses; moderately alkaline.
TYPE LOCATION: Pawnee County, Nebraska; about 6.4 kilometers (4 miles) north of Pawnee City; located about 483 meters (1584 feet) west and 107 meters (350 feet) south of the northeast corner of section 2, T. 2 N., R. 11 E.; Steinauer USGS quadrangle; latitude 40 degrees 10 minutes 26.9 seconds North and longitude 96 degrees 8 minutes 52.1 seconds West, NAD 83.
RANGE IN CHARACTERISTICS:
The soil moisture control section is usually wet in parts for a period from February to April due to a perched water table; dry in all parts for less than 45 consecutive days between June and September; moist throughout the rest of the year; udic moisture regime:
Mean annual soil temperature: 10 to 13 degrees C. (51 to 56 degrees F.)
Depth to argillic horizon: 18 to 48 centimeters
Depth to secondary calcium carbonate: 74 to 137 centimeters
Depth to redoximorphic concentrations: 18 to 33 centimeters
Depth to episaturation: 30 to 91 centimeters from February to April
Thickness of the mollic epipedon: 25 to 48 centimeters, commonly includes the upper part of the B horizon
Thickness of the solum: 102 to 152 centimeters
Particle-size control section (weighted average):
Clay content: 40 to 48 percent
Sand content: 20 to 35 percent
Rock fragments: 0 to 5 percent by volume
Size: gravel
A horizon:
Hue: 10YR
Value: 2 or 3, 3 to 5 dry
Chroma: 1 to 3 moist or dry
Texture: clay loam or loam
Clay content: 22 to 32 percent
Sand content: 15 to 35 percent
Reaction: strongly acid to slightly acid
BA horizon:
Hue: 10YR
Value: 2 to 3, 3 to 4 dry
Chroma: 2 to 3 moist or dry
Texture: clay loam or clay
Clay content: 28 to 42 percent
Sand content: 15 to 35 percent
Reaction: moderately acid to slightly acid
BA horizon may not always be present
Bt horizon:
Hue: 10YR, 2.5Y or 5Y
Value: 3 to 5, 3 to 6 dry
Chroma: 2 to 4 moist or dry
Redoximorphic Concentrations: hue: 7.5YR or 5YR; value: <5; chroma: <6
Texture: clay or clay loam
Clay content: 37 to 48 percent
Sand Content: 18 to 35 percent
Rock fragments: 0 to 5 percent gravel
Reaction: slightly acid to moderately alkaline
Note: Btss horizons are present in some pedons
BC horizon:
Hue: 10YR or 2.5Y or 5Y
Value: 4 to 6 moist, 5 to 8 dry
Chroma: 2 to 6 moist or dry
Redoximorphic Concentrations: hue: 7.5YR or 5YR; value: <5; chroma: <4
Texture: clay or clay loam
Clay content: 32 to 45 percent
Sand Content: 20 to 35 percent
Rock fragments: 0 to 5 percent gravel
Reaction: slightly alkaline or moderately alkaline
C horizon:
Hue: 10YR or 2.5Y or 5Y
Value: 4 to 7, 5 to 8 dry
Chroma: 1 to 6 moist or dry
Redoximorphic Concentrations:
Hue: 10YR, 7.5YR or 5YR
Value: <5
Chroma: <4
Texture: clay loam or clay
Clay content: 27 to 40 percent
Sand content: 25 to 35 percent
Rock fragments: 0 to 5 percent by volume
Reaction: slightly alkaline or moderately alkaline
COMPETING SERIES: These are the,
Baileyville,
Chillicothe and
Cornell soils. Baileyville and Chillicothe soils have less than 10 percent sand content within the series control section. Baileyville and Cornell soils have a lithologic discontinuity within the series control section.
GEOGRAPHIC SETTING:
Parent material: till
Landform: Hillslopes on dissected till plains
Slopes: 0 to 12 percent
Elevation: 244 to 512 meters (800 to 1680 feet)
Mean annual temperature: 11 to 13 degrees C (51 to 56 degrees F)
Mean annual precipitation: 737 to 991 millimeters (29 to 39 inches)
Frost-free period: 163 to 186 days
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Burchard, Mayberry, Shelby and Wymore soils. Burchard and Shelby soils are lower on the landscape and are fine-loamy in the control section. Burchard soils also have carbonates within 75 cm of the surface. Mayberry soils are on similar landscape positions but have redder hues. Wymore soils occur higher on the landscape and formed in loess.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: moderately well drained
Runoff: medium or rapid runoff
Saturated Hydraulic Conductivity: moderately low to low.
Seasonal high water saturation: common 30 to 91 centimeters in the spring.
USE AND VEGETATION: Most of the acreage is cropland with corn, soybeans, grain sorghum, and wheat as the principal crops. Some areas are used for hay and pasture. Native vegetation is tall and mid grass prairie.
DISTRIBUTION AND EXTENT: Southeast Nebraska and northeast Kansas; Land Resource Region M, Central Feed Grains and Livestock Region, Major Land Resource Area 106, Nebraska and Kansas Loess-Drift Hills; Extensive extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Pawnee County, Nebraska, 1920.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 36 to 86 centimeters. (upper 50 centimeters of Bt horizons)
Mollic epipedon: The zone from 0 to 36 centimeters. (Ap, A and BA horizons)
Argillic horizon: The zone from 36 to 114 centimeters. (Bt1, Bt2, Bt3 horizons)
Redoximorphic concentrations: In the zone from 25 to 200 centimeters. (BA, Bt, BC, and C horizons)
Vertic features: The presence of slickensides in some pedons at 36 to 114 centimeters. (Bt horizons)
Episaturation: The zone of saturation at 30 to 91 centimeters. (Bt horizons)
LRR=H
Modified format by LRM in 7/2006 to include metric conversion and change
permeability to saturated hydraulic conductivity.
GJ 5/15/2008 Removed English units, updated competing series, defined mean annual temperature as mean annual air temperature and removed the term glacial from till.
10/2008 JCR Added clay loam as a texture for the Bt and BC based on the
cumulative NSSL lab data for the Pawnee series. Clay content was lowered to 37 for both horizons.
7/2010 DJK Updated OSD to meet MO standards. Landform was changed from uplands to hillslopes on dissected till plains. MAP was changed from 76 cm to 864 mm. West-facing, 6% slope, and elevation of 372 meters was added to the typical pedon. Latitude was changed from 27 seconds to 26.9 and longitude from 5 seconds to 52.1 for type location.
Soil moisture control section information was updated with statements describing an udic moisture regime. Episaturation was changed from March to May to February to April. Sand content of PSCS was lowered from 45 to 35%.
In ROC for the A 3 was added for chroma, clay % changed from 15 to 41 to 22 to 32, sand % changed from 18 to 30 to 15 to 35, and reaction from moderately acid to slightly acid to strongly acid to slightly acid.
BA horizon was added into the ROC. In ROC for the Bt the sand content was change to 20 to 35 percent to match ROC for the control section. In ROC for the BC, value was changed from 5 or 6 moist or dry to 4 to 6 moist, 5 to 8 dry and clay % from 37 to 48 to 32 to 45
In ROC for the C horizon value was change from 5 moist to 4 to 7 moist and 5 or 6 dry to 5 to 8 dry. Textures of SCL and CL were eliminated and C was added. Clay % change from 15 to 40 to 27 to 40 and sand % from 10 to 25 to 25 to 35.
Competing series were edited by adding the statement "within the series control section" and Baileyville also has a litholigic discontinuity.
In geographic setting parent material was changed to clayey till from just till, landform from uplands to hillslopes on dissected till plains, elevation of 244 to 512 meters was added, MAP changed from 64 to 86 cm to 737 to 991 mm, and FFD from 160 to 180 to 163 to 186 days.
Geographically associated soils were updated with Aksarben, Arisburg, Crete, Morrill, and Steinauer being deleted.
Use and Vegetation was updated with crops being added and the statement on being irrigated deleted. The PSCS was changed from 36 to 114 to 36 to 86 cm and upper 50 cm of Bt statement added.
Redoximorphic concentrations bottom depth was changed from on down to actually say 200 cm. The possibility of slickensides being present was added to the vertic features and the sentence about clay percentages was deleted. Under additional data the NSSL pedons that have been correlated to Pawnee were added.
Additional data: Lab data is available for this pedon from the NSSL as pedon numbers: 58NE133001, 58NE133003, 71KS087003, 73NE109001, 80NE097001, 86KS085013, 86KS085014, 86KS085015, 86KS085022, 86KS117001, 86KS131001, 86KS131002, 86KS131003, 87KS131003, 88NE109001, S06KS131-001, and S06NE109-100.
National Cooperative Soil Survey
U.S.A.