LOCATION ROTAN TX

Established Series
Rev. CLG:JCW:GLL
11/2015

ROTAN SERIES

The Rotan series consists of deep, well drained, moderately slowly permeable soils that formed in calcareous loamy alluvium of the Quaternary age. These soils are on nearly level to very gently sloping terraces. Slope ranges from 0 to 3 percent. Mean annual precipitation is about 660 mm (26 in), and mean annual air temperature is about 17.8 degrees C (64 degrees F).

TAXONOMIC CLASS: Fine, mixed, superactive, thermic Pachic Paleustolls

TYPICAL PEDON: Rotan clay loam-cultivated.
Colors are for dry soil unless otherwise stated.

Ap--0 to 15 cm (0 to 6 in); brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; weak fine granular structure; hard, friable; slightly alkaline; abrupt smooth boundary. Thickness is 10 to 30 cm (4 to 12 in)

BA--15 to 36 cm (6 to 14 in); dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; hard, friable, sticky; common fine and very fine pores; few faint clay films on peds; slightly alkaline; clear wavy boundary. Thickness is 10 to 36 cm (4 to 14 in)

Bt1--36 to 64 cm (14 to 25 in); dark grayish brown (10YR 4/2) clay, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; very hard, firm, very sticky; common fine and very fine pores; nearly continuous clay films on peds; few films of calcium carbonate on peds; calcareous; moderately alkaline; clear wavy boundary. Thickness is 15 to 38 cm (6 to 15 in)

Bt2--64 to 122 cm (25 to 48 in); brown (7.5YR 4/4) clay, dark brown (7.5YR 3/4) moist; moderate medium blocky structure; very hard, firm, very sticky; few very fine pores; nearly continuous clay films on peds; common films and threads of calcium carbonate; calcareous; moderately alkaline; gradual wavy boundary. Thickness is 23 to 76 cm (9 to 30 in)

Btk1--122 to 173 cm (48 to 68 in); reddish yellow (7.5YR 8/6) clay loam, reddish yellow (7.5YR 6/6) moist; weak medium blocky structure; very hard, friable; sticky; few faint clay films on peds; contains about 25 percent visible soft masses and concretions of calcium carbonate; calcareous; moderately alkaline; gradual smooth boundary. Thickness is 20 to 76 cm (8 to 30 in)

Btk2--173 to 203 cm (68 to 80 in); reddish yellow (5YR 7/6) clay loam, yellowish red (5YR 5/6) moist; weak medium blocky structure; hard, firm; sticky; about 5 percent visible soft masses and concretions of calcium carbonate; few siliceous pebbles; few faint clay films on peds; calcareous; moderately alkaline.

TYPE LOCATION: Taylor County, Texas; from intersection of Farm Road 707 and Interstate 20 in the northern edge of Tye, one mile east along northern access road to Interstate 20, then 1 mile north on unnumbered paved county road to intersection with an unpaved county road, then 0.2 mile east on county road and 100 feet north into cultivated field.
USGS topographic quadrangle: Abilene West, TX;
Latitude: 32 degrees, 28 minutes, 29.55 seconds N;
Longitude: 99 degrees, 51 minutes, 19.27 seconds W;
Datum: WGS 84.
UTM Zone 14, UTM Easting 419625 m, UTM Northing 3593396 m.

RANGE IN CHARACTERISTICS:

Thickness of the mollic epipedon: 51 to 102 cm (20 to 40 in)
Depth to secondary calcium carbonate: 25 to 71 cm (10 to 28 in)
Depth to calcic horizon: 76 to 152 cm (30 to 60 in)

A Horizon
Hue: 7.5YR, 10YR
Value: 4 to 5
Chroma: 2 to 3
Texture: loam, clay loam, or silty clay loam
Reaction (pH): mildly alkaline to moderately alkaline (7.4 to 8.4)

Bt Horizon (above a calcic horizon)
Hue: 5YR, 7.5YR, 10YR
Value: 4 to 5
Chroma: 2 to 4
Texture: silty clay loam, clay loam, silty clay or clay
Total clay content: 35 to 45 percent
Structure: subangular blocky to angular blocky
Calcium carbonate equivalent: 0 to 10 percent
Effervescence: none to strong
Reaction (pH): mildly alkaline to moderately alkaline (7.4 to 8.4)

Btk Horizon
Hue: 5YR, 7.5YR, 10YR
Value: 5 to 8
Chroma: mainly 4 to 8, but may range down to 1
Texture: silty clay loam, clay loam, silty clay or clay
Total clay content: 27 to 45 percent
Identifiable secondary carbonate: 10 to 50 percent, masses and concretions
Calcium carbonate equivalent: 10 to 40 percent
Effervescence: strong to violent
Reaction (pH): moderately alkaline (7.9 to 8.4)

Btk Horizon (below a calcic horizon)
Hue: 2.5YR, 5YR, 7.5YR
Value: 5 to 7
Chroma: 6
Texture: silty clay loam, clay loam, silty clay or clay
Total clay content: 27 to 45 percent
Effervescence: strong to violent
Reaction (pH): moderately alkaline (7.9 to 8.4)

COMPETING SERIES: These are the Bethany and Darrouzett series in the same family. Similar soils include the Abilene, Dodson, Frankirk, Hollister, Roark, Rowena, and Sagerton series
Abilene, Dodson, and Roark soils: have argillic horizons that decrease in clay content within 152 centimeters (60 in), or have chromas of 4 or less throughout the Bt horizon
Bethany soils: do not have a calcic horizon and occur in a moister climate
Darrouzett soils: do not have a calcic horizon within 150 cm and occur in a drier climate
Frankirk and Sagerton soils: have mollic epipedons less than 51 centimeters (20 inches) thick
Hollister and Rowena soils: have vertic properties and do not have an argillic horizon

GEOGRAPHIC SETTING:
Parent material: calcareous alluvium presumably deposited during the Quaternary age
Landscape: Dissected plains
Landform: terraces
Slope: 0 to 3 percent
Mean annual precipitation: 508 to 737 mm (20 to 29 in)
Thornthwaite P-E Index: 28 to 44
Mean annual air temperature: 16.7 to 18.3 degrees C (62 to 65 degrees F)
Frost free days: 200 to 230
Elevation: 304.8 to 762.0 m (1000 to 2500 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Abilene, Hollister, Rowena, and Sagerton series and the Miles and Roscoe series.
Abilene and Sagerton soils: occur on similar positions
Hollister and Rowena soils: occur on similar to slightly lower positions
Miles soils: have less than 35 percent clay in the particle-size control section, do not have mollic epipedons, and occur on slightly higher convex positions.
Roscoe soils: have vertic properties, do not have argillic horizons, and occur on lower slightly concave positions.

DRAINAGE AND PERMEABILITY: Well drained; Permeability is moderately slow; Runoff is low on less than 1 percent slope and medium on 1 to 3 percent slopes.

USE AND VEGETATION: Mainly in cotton, grain sorghum, and wheat. Native vegetation is blue grama, sideoats grama, Arizona cottontop, buffalograss, and vine mesquite and mesquite trees.

DISTRIBUTION AND EXTENT: Rolling Plains of northwest Texas and probably southwestern Oklahoma. The series is moderately extensive.

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

SERIES ESTABLISHED: Stonewall County, Texas; 1970.

REMARKS: This series was formerly included with Abilene and Rowena soils.

Edited 11/2015 (RFG-ROG): Changed to tabular format. Added metric measurements. Updated competing series, geographic setting, and associated soils sections.

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon 0 to 64 cm (0 to 25 in)
Argillic horizon 36 to 203 cm (14 to 80 in)
Calcic horizon - 122 to 203 cm (48 to 80 in)

National Cooperative Soil Survey
U.S.A.