LOCATION CRAIG OK+MOEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, mixed, active, thermic Mollic Paleudalfs
TYPICAL PEDON: Craig silt loam - rangeland.
(Colors are for moist soil unless otherwise
stated.)
A11-- 0-7 inches, very dark brown (10YR 2/2) silt loam,
dark gray (10YR 4/1) dry; moderate medium and fine granular structure; hard, friable; many fine roots; common fine pores;
medium acid; gradual smooth boundary. (6 to 12 inches thick)
A12-- 7-12 inches, very dark grayish brown (10YR 3/2) silt loam, grayish brown (10YR 5/2) dry; weak fine granular structure; hard, friable; common fine roots and pores; few medium fragments
of chert; strongly acid; gradual smooth boundary. (0 to 10 inches thick)
A2-- 12-16 inches, dark grayish brown (10YR 4/2) silt
loam, light brownish gray (10YR 6/2) dry; weak medium granular structure; hard, friable; common fine roots and pores; few medium fragments of chert; strongly acid; gradual wavy boundary. (3 to 5 inches thick)
B1-- 16-21 inches, brown (10YR 5/3) silt loam, pale brown (10YR 6/3) dry; weak medium subangular blocky structure; hard, friable; few fine roots and pores; 10 percent medium fragments of chert; common 2 to 8 mm dark concretions; strongly acid; gradual
wavy boundary. (3 to 12 inches thick)
B21t-- 21-25 inches, dark yellowish brown (10YR 4/4) very cherty clay loam; yellowish brown (10YR 5/4) dry; moderate very
fine blocky structure; hard, friable; few fine roots and pores; 60
to 70 percent by volume of chert fragments from 2 mm to 100 mm in diameter; thin patchy clay films on faces of peds and chert fragments; common 2 to 5 mm dark concretions; strongly acid;
gradual wavy boundary. (4 to 16 inches thick)
B22t-- 25-42 inches, yellowish red (5YR 5/6) very cherty
clay loam; common fine, medium, and coarse reddish and brownish mottles on the chert fragments; weak very fine blocky structure; hard, friable; few fine roots and pores; 75 to 85 percent by
volume chert fragments from 2 mm to 100 mm; thin patchy clay films
on faces of peds, on chert fragments, and in pores; strongly acid; gradual wavy boundary. (10 to 30 inches thick)
B3-- 42-60 inches, yellowish red (5YR 5/6) very cherty
clay loam; common reddish and brownish mottles; structure is
obscured by the chert; hard, friable; fractured chert ranges from
2 mm to 100 mm in diameter and occupies about 85 percent of the volume; strongly acid.
TYPE LOCATION: Craig County, Oklahoma; about 5 miles southeast of Vinita; about 3150 feet south and 50 feet east of the northwest corner of sec. l2, T. 24 N., R. 20 E.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to more than 80 inches. The depth to horizons containing more than 35 percent chert by volume ranges from 15 to 30 inches. The soil
ranges from medium acid through very strongly acid throughout.
The A1 horizon is black (10YR 2/1), very dark brown (10YR 2/2),
very dark gray (10YR 3/1), very dark grayish brown (10YR 3/2), or dark brown (10YR 3/3). It is loam, silt loam, cherty loam, or
cherty silt loam. Coarse fragments more than 3 inches diameter
range from 0 to 5 percent of the volume and coarse fragments less than 3 inches diameter range from 0 to 35 percent of the volume.
The A2 horizon is dark gray (10YR 4/1), dark grayish brown (10YR 4/2), brown (10YR 4/3, 5/3), gray (10YR 5/1), or grayish brown
(10YR 5/2). Texture and coarse fragments are similar to those in
the A1 horizon.
The B1 horizon is very dark grayish brown (10YR 3/2), dark brown (10YR 3/3; 7.5YR 3/2), dark yellowish brown (10YR 3/4, 4/4), dark grayish brown (10YR 4/2), brown (10YR 4/3, 5/3; 7.5YR 4/2, 4/4,
5/2, 5/4), grayish brown (10YR 5/2), or yellowish brown (10YR
5/4). It is loam, silt loam, clay loam, silty clay loam, cherty loam, cherty silt loam, cherty clay loam, or cherty silty clay
loam. Coarse fragments more than 3 inches diameter range from 0
to 5 percent of the volume and coarse fragments less than 3 inches diameter make up 1 to 50 percent of the volume.
The B2t horizon is brown (10YR 4/3, 5/3; 7.5YR 4/4, 5/4), dark yellowish brown (10YR 4/4), yellowish brown (10YR 5/4, 5/6),
strong brown (7.5YR 5/6), reddish brown (5YR 4/3, 4/4, 5/3, 5/4),
or yellowish red (5YR 4/6, 5/6). The lower B2t horizon also
includes yellowish brown (10YR 5/8), pale brown (10YR 6/3); light yellowish brown (10YR 6/4), brownish yellow (10YR 6/6, 6/8),
strong brown (7.5YR 5/8), light brown (7.5YR 6/4), reddish yellow (7.5YR 6/6, 6/8), or yellowish red (5YR 4/8, 5/8). The B2t
horizon is cherty silty clay loam, cherty clay, cherty silty clay, very cherty silty clay loam, very cherty clay loam, very cherty
clay, or very cherty silty clay. The upper 20 inches clay
percentage ranges from 35 to 45. Coarse fragments more than 3
inches diameter range from 5 to 10 percent of the volume and
coarse fragments less than 3 inches diameter range from 35 to 90 percent of the volume
The B3 horizon is strong brown (7.5YR 5/6, 5/8), reddish yellow (7.5YR 6/6, 6/8; 5YR 6/6, 6/8), yellowish red (5YR 4/6, 4/8, 5/6, 5/8), red (2.5YR 4/6, 4/8, 5/6, 5/8), or light red (2.5YR 6/6,
6/8). It is very cherty clay loam or very cherty clay. Coarse fragments more than 3 inches diameter range from 5 to 10 percent
of the volume and coarse fragments less than 3 inches diameter
range from 65 to 90 percent of the volume.
An R layer of cherty limestone occurs at depths ranging from 5
feet to 30 feet below the surface.
COMPETING SERIES: These are the
Boxville,
Braxton,
Eldon,
Eldorado, and
Riverton series. Boxville and
Braxton soils have clayey control sections. Eldon soils have
messic temperatures. Eldorado and Riverton soils have
loamy-skeletal control sections.
GEOGRAPHIC SETTING: The Craig soils are on uplands. Slope gradients r from 0 to 5 percent, mainly less than 3 percent. The Craig soils
are formed in residuum weathered from cherty limestones. The
average annual precipitation ranges from about 37 to 47 inches,
the annual Thornthwaite P-E indices from 64 to about 80, and the average annual air temperature ranges from 57 degrees to about 62 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Eldorado series, and the Bates, Dennis, and Parsons series. Bates, Dennis, and Parsons soils contain little or no chert.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff;
moderately slow permeability.
USE AND VEGETATION: Some areas cultivated to small grains and sorghums. Some areas are in native range of tall prairie grasses
or in improved pasture. The native vegetation is tall grass
prairie.
DISTRIBUTION AND EXTENT: Northeastern Oklahoma and possibly in southwestern Missouri, northwestern Arkansas, and southeastern Kansas. The series is minor in extent.
MLRA OFFICE RESPONSIBLE: Salina, Kansas
SERIES ESTABLISHED: Craig County, Oklahoma; 1931.
REMARKS: The Craig soils were formerly classified in the Brunizem great soil group.