LOCATION MAY TX

Established Series
Rev. GLL
01/2017

MAY SERIES

The May series consists of very deep, well drained, moderately permeable soils formed in loamy alluvium. These nearly level and gently sloping soils occur along stream terraces. Slope ranges from 0 to 3 percent. Mean annual precipitation is about 762 mm (30 in), and mean annual air temperature is about 18.9 degrees C (66 degrees F).

TAXONOMIC CLASS: Fine-loamy, siliceous, active, thermic Udic Haplustalfs

TYPICAL PEDON: May fine sandy loam--cultivated.
(Colors are for dry soil unless otherwise stated.)

Ap--0 to 13 cm (0 to 5 in); grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine subangular blocky and granular structure; slightly hard, friable; neutral; abrupt smooth boundary. Thickness is 8 to 20 cm (3 to 8 in)

A--13 to 41 cm (5 to 16 in); grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine subangular blocky and granular structure; slightly hard, friable; few fine siliceous pebbles; neutral; clear smooth boundary. Combined thickness of the A horizon is 20 to 51 cm (8 to 20 in)

Bt1--41 to 76 cm (16 to 30 in); brown (10YR 4/3) sandy clay loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; hard, firm; thin discontinuous clay films on faces of peds; slightly alkaline; gradual wavy boundary. Thickness is 20 to 51 cm (8 to 20 in)

Bt2--76 to 107 cm (30 to 42 in); yellowish brown (10YR 5/4) sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; hard, firm; thin discontinuous clay films on faces of peds; slightly alkaline; clear wavy boundary. Combined thickness of the Bt horizon is 51 to 114 cm (20 to 45 in)

BC--107 to 127 cm (42 to 50 in); yellowish brown (10YR 5/4) sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak very fine subangular blocky structure; hard, friable; moderately alkaline; calcareous; gradual wavy boundary. Thickness is 0 to 30 cm (0 to 12 in)

Ck--127 to 152 cm (50 to 60 in); light yellowish brown (10YR 6/4) sandy clay loam, yellowish brown (10YR 5/4) moist; massive; hard, friable; common films and threads and a few soft masses of calcium carbonate; moderately alkaline; calcareous.

TYPE LOCATION: Erath County, Texas; from the county courthouse in Stephenville, Texas, about 14 miles north on Texas Highway 108 to the Hannibal store, then north on Highway 108, 0.9 mile, then west by northwest 2.9 miles on a county road to its intersection with a north-south county road, then 5.8 miles west on a county road and 0.4 mile south of road in a cultivated field.
USGS topographic quadrangle: Reddy Mountain, Texas;
Latitude: 32 degrees, 22 minutes, 54.62 seconds N;
Longitude: 98 degrees, 27 minutes, 40.32 seconds W;
Datum: WGS84.
UTM Easting 550680.86 m, UTM Northing 3582888.64 m, UTM Zone 14.

RANGE IN CHARACTERISTICS:
Solum thickness: 102 to 178 cm (40 to 70 in)
Depth to argillic horizon: 20 to 51 cm (8 to 20 in)
Depth to secondary calcium carbonate: 91 to 157 cm (36 to 62 in)

Particle-size control section (weighted average)
Clay content: 18 to 33 percent

A horizon
Hue: 10YR,
Value: 4 through 6
Chroma: 2 through 4; where moist value and chroma are 3 or less, organic matter is less than 1 percent
Texture: fine sandy loam or very fine sandy loam
Reaction (pH): slightly acid through mildly alkaline (6.1 to 7.8)

Bt horizon
Hue: 7.5YR and 10YR
Value: 4 through 6
Chroma: 2 through 6
Colors are brown, dark grayish brown, or yellowish brown
Texture: sandy clay loam, clay loam, or fine sandy loam
Clay content: 18 to 33 percent
Redox concentrations: few to common reddish or yellowish mottles in the lower part in some pedons
Reaction (pH): neutral or mildly alkaline (6.6 to 7.8)

BC or BCk horizon
Color: shades of brown
Redox concentrations: mottles in shades of yellow or brown in some pedons
Texture: sandy clay loam, loam, or fine sandy loam
Clay content: 15 to 33 percent
Effervescence: none to strong
Identifiable secondary carbonate: none to common; soft masses, threads or films
Reaction (pH): mildly alkaline or moderately alkaline

Ck horizon
Color: shades of brown, gray, or white with or without mottles or streaks or these colors
Texture: sandy clay loam, loam, or fine sandy loam.
Clay content: 10 to 30 percent
Identifiable secondary carbonate: few to many; soft masses, threads, and films
Effervescence: slight to violent
Reaction (pH): mildly alkaline or moderately alkaline

COMPETING SERIES: These are the Gholson, Lavender, and Personville series in the same family. Similar soils are the Cisco, Duffau, Konawa, Menard, and Weatherford series.
Gholson soils: occur in areas with a MAAT of 18.9 degrees C (66 degrees F) or higher and Thornthwaite P-E Index of 50 or more.
Lavender and Personville soils: are 152 cm or less deep to lithic limestone bedrock.
Cisco and Menard soils: have argillic horizons with redder hues and occur in a slightly drier soil moisture regime.
Konawa soils: have mixed mineralogy and has base saturation of the argillic horizon that ranges from 50 to 75 percent.
Duffau soils: do not have carbonates and have an argillic horizon with redder hues that have clay content that does not decease by more than 20 percent (relative) from the maximum within 152 cm of the soil surface.
Weatherford soils: are 152 cm or less deep to paralithic sandstone bedrock and has base saturation of the argillic horizon that ranges from 50 to 75 percent.

GEOGRAPHIC SETTING:
Parent material: loamy alluvium
Landscape: hills and river valleys
Landform: stream terraces
Slope: 0 to 3 percent
Mean annual precipitation: 711 to 965 mm (28 to 38 in)
Thornthwaite P-E Index: 40 to 50
Mean annual air temperature: 17.2 to 18.9 degrees C (63 to 66 degrees F)
Frost-free period: 210 to 240 days
Elevation: 213.4 to 609.6 m (700 to 2000 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bosque, Cisco, Duffau, Nimrod, Pedernales, and Windthorst series.
Bosque soils: have mollic epipedons and are lower in the landscape on flood plains.
Cisco and Duffau soils: occur higher in the landscape on stream divides and along upland drainageways.
Nimrod soils: have sandy epipedons 20 to 40 inches thick and are higher in the landscape on stream divides and low ridges.
Pedernales and Windthorst soils: have reddish clayey argillic horizons and are higher in the landscape on hillsides and stream divides.

DRAINAGE AND PERMEABILITY: Well drained; Permeability is moderate; Runoff is negligible on less than 1 percent slopes and low on 1 to 3 percent slopes. Most of the May soils occur in positions that receive extra water from adjacent higher areas.

USE AND VEGETATION: Mainly cultivated; grain sorghum, peanuts, and truck crops are the principal crops. Native vegetation is mid and tall grasses and post oak, live oak, and mesquite trees.

DISTRIBUTION AND EXTENT: North and central Texas; MLRAs 84B - West Cross Timbers, 80B - Texas North-Central Prairies, and fringe areas of 85 - Grand Prairie. The series is of moderate extent.

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

SERIES ESTABLISHED: Brown County, Texas; 1939.

REMARKS:
Edited 11/2013 (RFG-LAD): Converted to tabular format and added metric measurements. Updated competing series, geographic setting, and associated soils sections.

Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: 41to 91 cm (16 to 36 in) (Bt horizons)
Ochric epipedon: 0 to 41 cm (0 to 16 in) (A horizons)
Argillic horizon: 41 to 107 cm (16 to 42 in) (Bt horizons)

Taxanomic Version: Keys to Soil Taxonomy, 12th Edition, 2014.

National Cooperative Soil Survey
U.S.A.