LOCATION MEGUIN TXEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, hyperthermic Fluventic Haplustolls
TYPICAL PEDON: Meguin silty clay loam, linear, on 0.5 percent slope in pasture at an elevation of 16 m (53 ft)(Colors are for dry soil unless otherwise stated.)
A1--0 to 14 cm (0 to 6 in); dark gray (10YR 4/1) silty clay loam, very dark gray (10YR 3/1), moist; weak fine and medium subangular blocky structure and weak medium granular structure; slightly hard, friable; common fine roots and many very fine roots; common fine tubular and many fine and medium interstitial pores; strong effervescence; neutral; clear smooth boundary.
A2--14 to 45 cm (6 to 18 in); dark gray (10YR 4/1) silty clay loam, very dark gray (10YR 3/1), moist; moderate medium subangular blocky structure; slightly hard, friable; many very fine roots; common fine tubular and many very fine tubular pores; 1 percent shell fragments; strong effervescence; neutral; gradual smooth boundary. (Combined thickness of the A horizon is 20 to 51 cm [8 to 20 in])
Bw1--45 to 74 cm (18 to 29 in) light yellowish brown (10YR 6/4)loam, yellowish brown (10YR 5/4), moist; weak medium and coarse subangular blocky structure; slightly hard, very friable; common fine roots and many very fine roots; many very fine tubular pores; 1 percent fine distinct yellowish brown (10YR 5/6) masses of oxidized iron with sharp boundaries lining pores; 1 percent shell fragments; violent effervescence; moderately alkaline; clear smooth boundary.
Bw2--74 to 104 cm (29 to 41 in); pale brown (10YR 6/3)loam, brown (10YR 5/3), moist; moderate medium and coarse subangular blocky structure; slightly hard, friable; many very fine roots; common fine tubular and many very fine tubular pores; 1 percent fine faint dark yellowish brown (10YR 4/4) masses of oxidized iron with clear boundaries in matrix; 1 percent shell fragments; strong effervescence; slightly alkaline; gradual wavy boundary.
Bw3--104 to 126 cm (41 to 50 in); light brownish gray 10YR 6/2)clay loam, grayish brown (10YR 5/2), moist; weak medium subangular blocky structure; slightly hard, friable; common very fine roots; common very fine tubular pores; 2 percent fine and medium distinct dark yellowish brown (10YR 4/6) masses of oxidized iron with clear boundaries in matrix; 1 percent shell fragments; violent effervescence; moderately alkaline; gradual wavy boundary.
Bw4--126 to 155 cm (50 to 61 in); light gray (10YR 7/2) clay loam, grayish brown (10YR 5/2), moist; moderate medium and coarse subangular blocky structure; hard, firm; common very fine roots; common very fine tubular pores; 1 percent fine distinct dark yellowish brown (10YR 3/4) masses of oxidized iron with sharp boundaries lining pores and 1 percent fine black (10YR 2/1) iron-manganese masses with sharp boundaries in matrix surrounding redox concentrations; strong effervescence; slightly alkaline; clear wavy boundary. (Combined thickness of the Bw horizons is 99 to 152 cm [39 to 60 in])
Bssb--155 to 203 cm (61 to 80 in); gray (10YR 5/1) clay,dark gray (10YR 4/1), moist; weak medium wedge structure parting to moderate medium subangular blocky structure; very hard, very firm; common very fine roots; common very fine tubular pores; 15 percent prominent slickensides (pedogenic) on all faces of peds; 1 percent fine distinct dark yellowish brown (10YR 3/4) iron-manganese masses with sharp boundaries on faces of peds; 1 percent fine carbonate nodules; strong effervescence; slightly alkaline.
TYPE LOCATION: Goliad, Texas; from the intersection of Farm Road 1351 and Riverdale Road; 0.7 mile west on Farm Road 1351 to private ranch road; 0.8 mile north on private ranch road, 200 feet east in range. USGS quad Charco; Latitude is 28 degrees, 39 minutes, 45.50 seconds N; Longitude is 97 degrees, 33 minutes, 8.00 seconds W. NAD83.
RANGE IN CHARACTERISTICS:
Soil Moisture: An ustic soil moisture regime. The soil moisture control section remains dry in some or all parts for 90 or more but less than 180 cumulative days in normal years. Moist soil conditions occur mostly during the months of April through June and October through November. July through September and January through March are the driest months.
Mean annual soil temperature: 22.2 to 22.8 degrees C (72 to 73 degrees F).
Depth to cambic horizon: 45 to 155 cm (18 to 61 in)
Particle-size control section (weighted average)
Clay content: 25 to 30 percent
CEC/clay ratio: 0.60 to 0.70
A Horizon
Hue: 10YR
Value: 3 or 4
Chroma: 1 to 3
Texture: sandy clay loam, clay loam, or silty clay loam (A few areas have a clayey overwash)
Clay content: 21 to 35 percent
Calcium carbonate equivalent: 5 to 20 percent
Effervescence: slight or strong
Reaction: slightly or moderately alkaline
Bw Horizon
Hue: 10YR
Value: 4 to 7
Chroma: 2 to 4
Texture: loam, sandy clay loam, clay loam, or silty clay loam
Clay content: 27 to 35 percent
Effervescence: slight to violent
Reaction: slightly or moderately alkaline
Bssb Horizon
(where present)
Hue: 10YR
Value: 4 or 5
Chroma: 1 to 4
Texture: clay loam, silty clay loam, clay, or silty clay
Clay content: 30 to 55 percent
Calcium carbonate equivalent: 5 to 20 percent
Identifiable secondary carbonate: 0 to 2 percent
Effervescence: slight or strong
Reaction: slightly or moderately alkaline
COMPETING SERIES: There are no competing series. Similar soils are Asher, Ashport, Bridgeport, Degola, Goodcreek, Gowen, Grigston, Lamkin, and Sinton series.
Asher, Ashport, Goodcreek, and Lamkin soils: are in the thermic temperature regime.
Bridgeport and Grigston soils: are in the mesic temperature regime.
Degola and Sinton soils: are cumulic and fine-loamy.
Gowen is cumulic, fine-loamy and in the thermic temperature regime.
GEOGRAPHIC SETTING:
Parent material: calcareous loamy alluvium of Quaternary Age
Landform: crevasse filling on river valley
Slope: 0 to 1 percent
Mean annual air temperature range: 21 to 23 degrees C (70 to 73 degrees F).
Mean annual precipitation range: 711 to 914 mm (28 to 36 in)
Precipitation Pattern: Precipitation falls mostly during the months of April through June and October through November. July through September and January through March are the driest months.
Frost-free period: 248 to 285 days
Elevation: 46 to 122 m (150 to 400 ft)
Thornthwaite annual P-E indices: 38 to 48
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Buchel, Odem, Sinton, and Zunker series.
Buchel soils: are clayey throughout and are on a backswamp landform.
Odem soils: are noncalcareous, have less clay throughout, and are on a natural levee landform.
Sinton soils: have more than 50 cm (20 in) of mollic epipedon and are on a similar landform.
Zunker soils: have a lighter colored surface layer, have less clay throughout, and are on a point bar landform.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is negligible. Flooding occurs from 5 to more than 50 times in 100 years for very brief to brief periods. Flooding typically occurs during the months of April through June.
USE AND VEGETATION: Used for mostly crop production and livestock grazing. Major crops grown include grain sorghum, wheat, or corn. The majority of the livestock grazing areas are planted to coastal bermudagrass. Native vegetation id dominantly bluestems, fourflower trichloris, vine mesquite, big sandbur, switchgrass, Texas wintergrass, and hackberry trees. The ecological site is Loamy Bottomland (083AY573TX).
DISTRIBUTION AND EXTENT: South Central Texas; LRRI (Southwest Plateaus and Plains Range and Cotton Region); MLRA 83A (Northern Rio Grande Plain); the series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Goliad County, Texas, 2007.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 25 to 100 cm (10 to 40 in). (A2, Bw1, and Bw2 horizons)
Mollic epipedon: 0 to 45 cm (0 to 18 in). (A1 and A2 horizons)
Cambic horizon: 104 to 203 cm (41 to 80 in). (Bw3, Bw4, and Ab horizons)
Buried horizon: 155 to 203 cm (61 to 80 in). (Ab horizon)
Redoximorphic concentrations: In the zone from 45 to 203 cm (18 to 203 in). (Bw1, Bw2, Bw4, and Ab horizons)
Vertic features: The presence of slickensides at 155 to 203 cm (61 to 80 in). (Bssb horizon)
ADDITIONAL DATA: NSSL Data from type location S07TX175001.
TAXONOMIC VERSION: Keys to Soil Taxonomy, Tenth Edition, 2006