LOCATION LOCO               OK
Established Series
Rev. LEK:JWF:ELC
04/2003

LOCO SERIES


The Loco series consists of shallow, well drained, moderately permeable soils that formed in interbedded gray clayey shale and siltstone of the Permian age. These soils are on convex
ridgetops of uplands in the Central Rolling Red Prairies. Slopes
are dominantly 5 to 8 percent but range from 3 to 8 percent.

TAXONOMIC CLASS: Loamy, mixed, superactive, thermic, shallow Typic Haplustolls

TYPICAL PEDON: Loco silty clay loam, on a convex 5 percent
slope, in native grass.
(Colors are for dry soil unless otherwise
stated.)

A--0 to 6 inches; dark grayish brown (10YR 4/2) silty clay
loam, very dark grayish brown (10YR 3/2) moist; moderate medium
and fine granular structure; slightly hard, friable; many roots;
many wormcasts; calcareous; moderately alkaline; gradual smooth boundary. (4 to 8 inches thick)

Bw--6 to 17 inches; light brownish gray (2.5Y 6/2) silty clay loam, grayish brown (2.5Y 5/2) moist; strong medium and fine subangular blocky structure; hard, friable; many roots; common wormcasts; few soft fragments of siltstone; few soft bodies and
films of calcium carbonate; calcareous; moderately alkaline;
gradual wavy boundary. (7 to 12 inches thick)

Cr--17 to 26 inches; gray (5Y 6/1) clayey shale, gray (5Y
5/1) moist; massive; extremely hard, firm; level bedded,
fractured; few roots in seams and fractures; many films and soft bodies of calcium carbonate; calcareous; moderately alkaline.

TYPE LOCATION: Garvin County, Oklahoma; approximately 4 miles
north and 2 1/2 miles west of Pernell; 900 feet north, 2,100 feet east of the southwest corner of sec. 19, T. 2 N., R. 3 W.

RANGE IN CHARACTERISTICS: Solum thickness and depth to bedrock ranges from 10 to 20 inches. The soil is calcareous and
moderately alkaline in all horizons.

The A horizon has hue of 10YR or 2.5Y, value of 4 or 5, and
chroma of 2 or 3. Texture is loam, silt loam, or silty clay
loam.

The Bw horizon has hue of 10YR to 5Y, value of 5 to 7, and chroma
of 2 to 4. Texture is silt loam or silty clay loam and the clay content ranges from 18 to 35 percent. Soft bodies of calcium carbonate range from few to many.

The Cr horizon has hue of 2.5Y or 5Y, value of 6 or 7, and chroma
of 1 to 4. The Cr horizon is calcareous clayey shale that is
easily dug with a spade. Some pedons have interbedded siltstone.

COMPETING SERIES: These are Lucien series in the same family and Acme, Cordell, Cornick, Cottonwood, Darnell, Ector, Grainola, Lenapah, Lueders, Owens, Quinlan, Shidler, Talpa, and Vernon
series in similar families. Acme and Cornick soils lack cambic horizons, are dry for longer periods and are underlain with
gypsum. In addition, Cornick soils are less than 10 inches
thick. Cordell and Quinlan soils lack a mollic epipedon and have
Bw horizons with hue of 5YR or redder. In addition, Cordell
soils have a lithic contact. Cottonwood and Darnell soils lack mollic epipedons. In addition, Darnell soils has siliceous mineralogy. Ector, Lueders, and Talpa soils have lithic
contacts. In addition, Ector and Lueders soils have
loamy-skeletal control sections. Grainola, Owens, and Vernon
soils have a fine control section and lack a mollic epipedon. In addition, Grainola and Vernon soils are more than 20 inches
thick. Lenapah and Shidler soils have a lithic contact. In addition, Lenapah soils have a fine control section. Lucien
soils have a Bw horizon with hue of 7.5YR or redder and are
neutral to medium acid in reaction.

GEOGRAPHIC SETTING: Loco soils are on gently sloping to sloping convex upland ridgetops of the Central Rolling Red Prairies.
Slopes range from 3 to 8 percent. These soils formed in material weathered from interbedded gray clayey shale and soft siltstone. Mean annual precipitation ranges from 32 to 36 inches. Mean
annual temperature ranges from 60 to 63 degrees F. Thornthwaite annual P-E indices range from 48 to 58.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Zaneis series.
Zaneis soils are more than 20 inches thick and occur on adjacent
side slopes.

DRAINAGE AND PERMEABILITY: Loco soils are well drained. Runoff
is medium to rapid, and permeability is moderate.

USE AND VEGETATION: Used as rangeland for beef cattle. Native vegetation is mainly tall and mid grasses.

DISTRIBUTION AND EXTENT: Central Rolling Red Prairies of south central Oklahoma. The series is of minor extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Garvin County, Oklahoma; 1982.

REMARKS: Loco soils were formerly included in the Lucien and Kip series.

ADDITIONAL DATA: Oklahoma State University Lab. No. 77-OK-25-1.


National Cooperative Soil Survey
U. S. A.