LOCATION VENUS                   TX

Established Series
Rev. ALN-WRE-GSM-GLL-CLN
12/2016

VENUS SERIES

The Venus series consists of very deep, well drained, moderately permeable soils that formed in loamy calcareous alluvial sediments. These nearly level to moderately sloping soils occur mainly on stream terraces and footslopes of hills and ridges. Slope ranges from 0 to 8 percent. Mean annual air temperature is about 19 degrees C (66 degrees F), and the mean annual precipitation is about 864 mm (34 in).

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Udic Calciustolls

TYPICAL PEDON: Venus loam--in cropland.
(Colors are for dry soil unless otherwise stated.)

Ap--0 to 15 cm (0 to 6 in); dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine granular and fine subangular blocky structure; hard, friable; many wormcasts; few fragments of shells and fine slightly pitted calcium carbonate concretions; violently effervescent; moderately alkaline; abrupt smooth boundary.

A--15 to 36 cm (6 to 14 in); dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; hard, friable, crumbly; common granular wormcasts; few fine slightly pitted calcium carbonate concretions and fragments of shells; violently effervescent; moderately alkaline; gradual smooth boundary. Combined thickness of the A horizon is 25 to 51 cm (10 to 20 in)

Bk1--36 to 76 cm (14 to 30 in); grayish brown (10YR 5/2) loam, dark grayish brown (10YR 4/2) moist; moderate fine subangular blocky and granular structure; hard, friable, crumbly; common wormcasts; few fine slightly pitted calcium carbonate concretions and fragments of shells; many films and threads and a few soft masses of calcium carbonate; 18 percent calcium carbonate equivalent; few quartz gravel; violently effervescent; moderately alkaline; gradual boundary. Thickness is 15 to 56 cm (6 to 22 in)

Bk2--76 to 127 cm (30 to 50 in); very pale brown (10YR 7/3) loam, pale brown (10YR 6/3) moist; moderate very fine and fine granular structure; hard, friable, very crumbly; common filled worm channels; common fine, slightly pitted calcium carbonate concretions; many films and threads and common soft masses of calcium carbonate; 19 percent calcium carbonate equivalent; few quartz gravel; violently effervescent; moderately alkaline; gradual boundary. Combined thickness of the Bk horizon is 35 to 127 cm (14 to 50 in)

BCk--127 to 152 cm (50 to 60 in); very pale brown (10YR 7/3) fine sandy loam, pale brown (10YR 6/3) moist; weak fine subangular blocky structure; hard, friable; few lenses of fine quartz and limestone gravel; common soft bodies of calcium carbonate; 20 percent calcium carbonate equivalent; violently effervescent; moderately alkaline.

TYPE LOCATION: Erath County, Texas; From the intersection of Farm Road 1189 and U.S. Highway 281 in of Morgan Mill, 7.9 miles northeast on Farm Road 1189, 2.2 miles north and east on county road, and 320 yards south in cropland.
USGS topographic quadrangle: Bluff Dale NE;
Latitude: 32 degrees, 29 minutes, 15.5 seconds N;
Longitude: 98 degrees, 5 minutes, 1.8 seconds W;
Datum: NAD83

RANGE IN CHARACTERISTICS:
Soil moisture: Udic ustic moisture regime.
Solum thickness: 150 to 200 cm (60 to 80 in)
Mollic epipedon: 25 to 50 cm (10 to 20 in)
Coarse fragments: 0 to 10 percent by volume, siliceous gravel

Particle-size control section (weighted average)
Total clay content: 18 to 35 percent
Silicate clay content: 18 to 30 percent
Calcium carbonate equivalent: 15 to 40 percent

A horizon
Hue: 7.5YR to 2.5Y
Value: 4 or 5, 2 or 3 moist
Chroma: 2 or 3, dry and moist
Texture: Loam, sandy clay loam, or clay loam
Calcium carbonate concretions: 0 to 2 percent by volume
Calcium carbonate equivalent: 10 to 40 percent
Effervescence: slight to violent
Reaction (pH): slightly alkaline or moderately alkaline (7.4-8.4)

Bk horizon
Hue: 7.5YR to 2.5Y
Value: 4 to 7, 3 to 6 moist
Chroma: 3 to 6, dry and moist
Texture: Loam, sandy clay loam, or clay loam
Visible secondary carbonates: 5 to 20 percent by volume, concretions, films, threads, and masses
Calcium carbonate equivalent: 15 to 40 percent
Effervescence: strong to violent
Reaction (pH): slightly alkaline or moderately alkaline (7.4-8.4)

BCk horizon
Hue: 7.5YR to 2.5Y
Value: 5 to 8, 4 or 6 moist
Chroma: 3 to 6, dry and moist
Texture: Fine sandy loam, loam, sandy clay loam, or clay loam; Some pedons are underlain by layers of sand and gravel at depths of about 1.2 to 2.4 m (4 to 8 ft)
Coarse fragments: 0 to 30 percent by volume, limestone and/or siliceous gravel
Calcium carbonate equivalent: 10 to 60 percent
Effervescence: strong to violent
Reaction (pH): slightly alkaline or moderately alkaline (7.4-8.4)

COMPETING SERIES: There are no other series in the same family. Similar series are the Bolar, Lewisville, Nuvalde, Rumley, Topsey, and Sunev series.
Bolar, Rumley, Topsey, and Sunev soils: have more than 40 percent calcium carbonate equivalent in the particle-size control section, in addition Bolar soils have bedrock at a depth of 51 to 102 cm (20 to 40 in).
Lewisville and Nuvalde soils: have a fine-silty particle-size control section

GEOGRAPHIC SETTING:
Parent material: thick beds of unconsolidated calcareous, loamy alluvial sediments of Pleistocene age.
Landscape: hills and dissected plateaus
Landform: Stream terraces and footslopes of hills and ridges. Some areas adjacent to the stream channel may be rarely to occasionally flooded for very brief periods in the spring and fall months
Slope: 0 to 8 percent, but are dominantly 1 to 5 percent
Precipitation Pattern: The majority of the yearly amount occurs during the fall and spring months. The winter and summer months are normally drier.
Mean annual precipitation: 711 to 1,016 mm (28 to 40 in)
Thornthwaite annual P-E Index: 44 to 64
Mean annual air temperature: 16.7 to 20.0 degrees C (62 to 68 degrees F)
Frost free days 220 to 250
Elevation: 137.1 to 640.1 m (450 to 2,100 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Altoga, Bosque, Karnes, and Lewisville series.
Altoga soils: have a fine-silty particle-size control section, an ochric epipedon, and occur on similar positions.
Bosque soils: occur on flood plains and have a mollic epipedon more than 50 cm (20 in) thick
Karnes soils: have an ochric epipedon and occur on similar positions
Lewisville soils: have a fine-silty particle-size control section and occur on similar positions

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is negligible on slopes less than 1 percent, low on 1 to 5 percent slopes, and medium on 5 to 8 percent slopes.

USE AND VEGETATION: Mostly cultivated, mainly to small grains. Original vegetation was tall and mid grass and widely spaced live oak and other hardwoods.

DISTRIBUTION AND EXTENT: Areas are in Texas and possibly in Oklahoma. LRR-I and J. Mostly in the MLRA 85-Grand Prairie and MLRA 81C-Edwards Plateau, Eastern part. The series is of large extent.

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

SERIES ESTABLISHED: Bexar County, Texas; 1964.

REMARKS: Classification was changed 11/89 from Typic Calciustolls to Udic Calciustolls.

Edited 12/2016 (RFG-TRD): Added CCE to the range in characteristics. Updated competing series, geographic setting, and associated soils sections.

Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: 25 to 100 cm (10 to 40 in)
Mollic epipedon: 0 to 36 cm (0 to 14 in) (Ap and A horizons)
Calcic horizon: 36 to 152 cm (14 to 60 in) (Bk1 and Bk2 horizons)

ADDITIONAL DATA: Lab data available from NSSL; Bell County, Texas No. 81P1582-1588, 18207-18216.

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014.

---

National Cooperative Soil Survey
U.S.A.