LOCATION ODEM TXEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, hyperthermic Cumulic Haplustolls
TYPICAL PEDON: Odem fine sandy loam, rangeland on a northeast-facing, convex, 0.7 percent slope in rangeland at an elevation of 8.5 m (28 ft). Colors are for dry soil unless otherwise stated.)
A--0 to 41 cm (0 to 16 in); dark gray (10YR 4/1) fine sandy loam, very dark gray (10YR 3/1) moist; weak fine and very fine granular structure; slightly hard, friable; many fine roots; many fine and medium pores; neutral; diffuse smooth boundary. (5 to 24 in thick)
Bw1--41 to 102 cm (16 to 40 in); dark gray (10YR 4/1) fine sandy loam, very dark gray (10YR 3/1) moist; moderate coarse prismatic structure parting to weak fine subangular blocky; slightly hard; friable; few fine roots; few fine and medium pores; slightly alkaline; gradual smooth boundary. (combined thickness of the Bw horizons is 142 to 193 cm [56 to 75 in] thick)
Bw2--102 to 203 cm (40 to 80 in); grayish brown (10YR 5/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, friable; few thin strata and bedding planes of loamy fine sand mainly in the lower part; few fine pores; strongly effervescent; moderately alkaline.
TYPE LOCATION: San Patricio County, Texas.; from the intersection of U.S. Highway 181 and U.S. Highway 77 in Sinton; 7.3 miles north on U.S. Highway 77 to entrance of Rob and Bessie Welder Wildlife Refuge; 1.7 miles east on entrance road to intersection; 1.6 miles south and east on paved ranch road to Y intersection; left and northeast 0.9 miles to intersection; northwest and north 0.4 mile on gravel road past windmill to intersection; 400 feet west and 50 feet south in rangeland. This point is about 0.5 mile west of Venado Tank, and 0.3 mile south of Aransas River. Woodsboro USGS quad; Latitude is 28 degrees, 07 minutes, 34 seconds N; Longitude is 97 degrees, 22 minutes, 30 seconds W; NAD 83
RANGE IN CHARACTERISTICS: Solum thickness ranges from 152 cm to more than 203 cm (60 to more than 80 in). Thickness of the mollic epipedon ranges from. Clay content of the 10 to 40 inch particle-size control section ranges from 10 to 18 percent.
Soil Moisture: An ustic soil moisture regime. The soil moisture control section is dry in some or all parts for more than 90 cumulative days in normal years. Soil moisture conditions are driest from July through August. September through November is the wettest.
Mean annual soil temperature: 22 to 23.5 degrees C (72 to 74 degrees F).
Thickness of the mollic epipedon: 51 to 140 cm (20 to 55 in)
Particle-size control section (weighted average)
Clay content: 10 to 18 percent
A Horizon
Hue: 10YR
Value: 3 to 5
Chroma: 1 to 3
Texture: loamy fine sandy, fine sandy loam, or loam
Effervescence: none or very slight
Reaction: slightly acid to moderately alkaline
Bw1 Horizon
Hue: 10YR
Value: 3 to 5
Chroma: 1 to 3
Texture: loamy fine sandy, fine sandy loam, or loam
Effervescence: none or very slight
Reaction: neutral to moderately alkaline
Bw2 Horizon
Hue: 10YR
Value: 4 to 7
Chroma: 1 to 3
Texture: loamy fine sandy, fine sandy loam, or loam (Some pedons have thin strata of various textures ranging from sandy clay loam to sand)
Effervescence: none or very slight
Reaction: neutral to moderately alkaline
C Horizon (where present)
Hue: 10YR
Value: 5 to 7
Chroma: 1 to 3
Texture: loamy fine sandy, fine sandy loam, or loam (Some pedons have thin strata of various textures ranging from sandy clay loam to sand)
Effervescence: none or very slight
Reaction: neutral to moderately alkaline
COMPETING SERIES: There are no other series in this family. Similar soils include the
Bosque (TX),
Cyril (OK),
Degola (TX),
Ramadero (TX), and
Sinton (TX) series.
Bosque and Cyril soils: have mean annual soil temperatures of less than 72 degrees F
Bosque, Degola, Ramadero, and Sinton soils: have more than 18 percent clay in their particle-size control section.
GEOGRAPHIC SETTING:
Parent material: loamy alluvial sediments of Holocene age
Landscape: coastal plain
Landform: natural levee
Slope: generally less than 1 percent but range up to about 3 percent
Mean annual air temperature range: 21 to 23 degrees C (70 to 73 degrees F).
Mean annual precipitation range: 584 to 918 mm (23 to 36 in)
Precipitation Pattern: The majority of the yearly amount occurs during the fall and spring months. The summer months are normally dry with infrequent coastal showers. The late summer months are subject to periods of high intense rainfall as a result of tropical disturbances.
Frost-free period: 275 to 300 days
Elevation: 7.6 to 91 m (25 to 300 ft)
Thornthwaite annual P-E indices: 31 to 44
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing
Aransas (TX) series and the
Sinton (TX) series.
Aransas soils: have a clayey particle-size control section; are on a lower position on the floodplain
Sinton soils: have more than 18 percent clay in the particle-size control section; occur on a similar to slightly lower position on the floodplain.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately rapid. Runoff is negligible. These soils are inundated with floodwaters for very brief to brief periods on the average of 1 to 40 times in 100 years.
USE AND VEGETATION: Used for cropland, improved pastures, and rangeland. Cotton, grain sorghum, and corn are the main crops grown. Native vegetation consists of occasional hackberry and anacua trees, few scattered invading mesquite and huisache trees. Range grasses are seacoast bluestem, balsamscale, sideoats grama, knotroot panicum, and threeawn. (Ecological site name: Loamy Bottomland 25-44" Pz
Ecological site number: R150AY534TX)
DISTRIBUTION AND EXTENT: Rio Grande Plain (MLRA 83A) and Gulf Coast Prairies (MLRA 150A) of Texas. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: San Patricio County, Texas; 1971.
REMARKS: These soils were previously included with the Zavala series.
Diagnostic horizons and features in this pedon are:
Mollic epipedon - the zone from the surface of the soil to a depth of approximately 102 cm (40 in). (A, Bw1 horizons)
ADDITIONAL DATA: Lab data available on pedons from Goliad County from local lab.
TAXONOMIC VERSION: Keys to Soil Taxonomy, Tenth Edition, 2006