LOCATION PRATT KS+OKEstablished Series
The Pratt series consists of very deep, well drained, rapidly permeable soils that formed in sandy eolian deposits on dunes on paleo-terraces in river valleys of the Great Bend Sand Plains (MLRA 79). Mean annual temperature is 56 degrees F (13 degrees C), and mean annual precipitation is 29 inches (74 centimeters).
TAXONOMIC CLASS: Sandy, mixed, mesic Lamellic Haplustalfs
TYPICAL PEDON: Pratt fine sand - in a cultivated field. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 8 inches (0 to 20 centimeters); light yellowish brown (10YR 6/4), interior, fine sand, yellowish brown (10YR 5/4), interior, moist; single grain; loose, loose, nonsticky and nonplastic; 5.0 percent clay; moderately acid; clear smooth boundary. (7 to 20 inches thick; 18 to 50 centimeters thick)
Bt--8 to 24 inches (20 to 61 centimeters); brownish yellow (10YR 6/6), interior, loamy fine sand, yellowish brown (10YR 5/6), interior, moist; weak fine and medium subangular blocky structure parting to single grain; soft, very friable, nonsticky and nonplastic; 11 lamellae 3-12 mm thick fine sandy loam 7.5YR 4/4; 9.0 percent clay; few distinct patchy clay bridging between sand grains; in the matrix, common distinct discontinuous clay bridging between sand grains in the lamellae; strongly acid; clear wavy boundary. (15 to 40 inches thick; 38 to 102 centimeters thick)
E&Bt--24 to 64 inches (61 to 163 centimeters); (E) fine sand, yellowish brown (10YR 5/6), interior, and brownish yellow (10YR 6/6), interior, moist, single grain, loose, loose, nonsticky and nonplastic, 3.0 percent clay; (Bt) 3 lamellae 4mm thick yellowish brown (10YR 5/4), interior, loamy fine sand, dark yellowish brown (10YR 4/4), interior, moist, weak fine and medium subangular blocky structure parting to single grain, loose, loose, nonsticky and nonplastic, few distinct discontinuous clay bridging between sand grains; moderately acid; gradual wavy boundary. (20 to 50 inches thick; 50 to 127 centimeters thick)
C--64 to 80 inches (163 to 203 centimeters); light yellowish brown (10YR 6/4), interior, fine sand, yellowish brown (10YR 5/4), interior, moist; single grain; loose, loose, nonsticky and nonplastic; 5.0 percent clay; moderately acid.
TYPE LOCATION: Reno County, Kansas; 7 miles (11.3 kilometers) west of Langdon; 2240 feet (683 meters) east and 400 feet (122 meters) north of the southwest corner, sec. 20, T. 25 S., R. 10 W.; (USGS Turon topographic quadrangle; lat. 37 degrees 51 minutes 16 seconds N. and long. 98 degrees 26 minutes 44.5 seconds W.)
RANGE IN CHARACTERISTICS:
Soil moisture regime: ustic moisture regime bordering on udic
Soil temperature regime: mesic
Mean annual soil temperature: 56 to 58 degrees F (13 to 14 degrees C)
Particle-size control section: 4 to 11 percent clay
Depth to secondary calcium carbonate: typically greater than 80 inches (203 centimeters)
Thickness of the ochric epipedon: 7 to 20 inches (18 to 50 centimeters)
A horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6 (dry) 3 to 5 (moist)
Chroma: typically 2 to 4 but range includes 1
Texture: sand, fine sand, loamy sand, or loamy fine sand
Reaction: strongly acid to neutral
Bt horizon:
Hue: typically 10YR, 7.5YR, range includes 5YR
Value: 4 to 6 (dry) 4 to 5 (moist)
Chroma: 2 to 6
Texture: loamy sand or loamy fine sand
In some pedons this horizon consists of a bridged sandy matrix alternating with lamellae. Textures of these lamellae includes fine sandy loam, loamy fine sand, sandy
loam, or loamy sand.
Reaction: strongly acid to neutral
E & Bt horizon:
Hue: 7.5YR or 10YR (E) 7.5YR (Bt)
Value: 5 to 7 (dry) 4 to 6 (moist) (E) 4 to 5 (dry) 3 to 6 (moist) (Bt)
Chroma: 4 to 6 (E) 3 to 6 (Bt)
Texture: sand, fine sand, or loamy fine sand (E); loamy sand, fine sandy loam, or loamy fine sand (Bt)
Reaction: strongly acid to neutral
C horizon:
Hue: 10YR or 7.5YR
Value: 5 to 7 (dry) 4 to 6 (moist)
Chroma: 3 to 6
Texture: loamy fine sand or fine sand
Calcium carbonate equivalent: 0 to 2 percent
Reaction: slightly acid to neutral
COMPETING SERIES: The Turon (KS) series is the only other series in this family. Turon soils have a buried soil greater than 40 inches (102 centimeters).
GEOGRAPHIC SETTING: Pratt soils
Parent material: sandy eolian deposits
Landform: dunes on paleo-terraces, also on terraces and in some places floodplains.
Slopes: 0 to 15 percent
Elevation: 750 to 2200 feet (228.6 to 670.6 meters)
Mean annual air temperature: 57 to 64 degrees F (14 to 18 degrees C)
Mean annual precipitation: 19 to 32 inches (48 to 81 centimeters)
Wettest months: Mar. - Oct.
Driest months: Nov. - Feb.
Frost-free period: 185 to 225 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Attica, Carbika, Carway , Carwile, Hayes, Langdon, Naron, Shellabarger, Tivin, Tivoli, Turon and Warnut soils. The finer textured Attica, Naron, and Shellabarger soils are on slightly less undulating topography. Hayes, Langdon, Tivin and Tivoli soils are on steeper slopes. The wetter, finer textured Carbika, Carway, Carwile and Warnut soils are in nearby depressions.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is low. Permeability is rapid.
USE AND VEGETATION: Gentler slopes are usually cultivated; grain sorghum is the principal crop with lesser acreage of wheat and alfalfa. Steeper slopes are mostly in native range. Native vegetation is dominated by sand bluestem, indiangrass, and little bluestem.
DISTRIBUTION AND EXTENT: South Central Kansas. LRR H Great Plains Winter Wheat and Range, MLRA 79 Great Bend Sand Plains. The series is of large extent.
MLRA OFFICE RESPONSIBLE: Salina, Kansas
SERIES ESTABLISHED: Pratt County, Kansas, 1910.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon: The zone from 0 to 8 inches (0 to 20 centimeters). (Ap)
argillic horizon: The zone from 8 to 24 inches (20 to 61 centimeters) and containing lamellae. (Bt)
Keys to Soil Taxonomy: Eighth edition, 1998
ADDITIONAL DATA: For additional information refer to Soil Survey Investigation Report No. 4, pages 56 to 59.
Pratt TP 93KS155129
PRATT
LRR=H
2/08/95: Update series for Oklahoma