LOCATION MOLLVILLE TX+LAEstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, active, thermic Typic Glossaqualfs
TYPICAL PEDON: Mollville loam--woodland. (Colors are for moist soil unless otherwise stated.)
Oe--2 to 0 inches; humus and oak leaves with light gray (10YR 7/1) grains of silt loam; very strongly acid.
A--0 to 5 inches; dark gray (10YR 4/1) loam; weak medium granular structure; slightly hard, friable; many fine roots; very strongly acid; clear wavy boundary. (2 to 8 inches thick)
Eg--5 to 11 inches; light brownish gray (10YR 6/2) loam, light gray (10YR 7/1) dry; weak medium subangular blocky structure; slightly hard, friable; many fine roots; very slightly saline; strongly acid; clear irregular boundary. (4 to 14 inches thick)
Btg/E1--11 to 23 inches; grayish brown (10YR 5/2) sandy clay loam; about 20 percent of horizon is vertical intrusions, spots, and streaks of light gray (10YR 7/2) albic materials (E); moderate medium prismatic structure parting to moderate medium subangular blocky; very hard, very firm; few fine roots; many prominent dark grayish brown clay films; many medium prominent strong brown (7.5YR 5/6) masses of iron accumulation; very slightly saline; strongly acid; clear wavy boundary. (8 to 30 inches thick)
Btg/E2--23 to 42 inches; prominently variegated gray (10YR 5/1), grayish brown (10YR 5/2) and strong brown (7.5YR 5/6) sandy clay loam; about 5 percent of the horizon is vertical intrusions, streaks, and spots of light gray (10YR 7/2) albic materials (E); moderate medium subangular blocky structure; very hard, very firm; few fine roots; common prominent clay films; very slightly saline; strongly acid; clear wavy boundary. (8 to 30 inches thick)
Btg--42 to 47 inches; prominently variegated light brownish gray (10YR 6/2), grayish brown (10YR 5/2) and strong brown (7.5YR 5/6) clay loam; few streaks of albic materials; moderate medium subangular blocky structure; very hard, very firm; few fine roots; common faint clay films; very slightly saline; slightly acid; clear wavy boundary. (0 to 15 inches thick)
BCtg--47 to 54 inches; prominently variegated light gray (10YR 7/2) and strong brown (7.5YR 5/6) sandy clay loam; moderate medium subangular blocky structure; hard, firm; few fine roots; few faint clay films; very slightly saline; neutral; clear wavy boundary. (0 to 10 inches thick)
2Cg--54 to 80 inches; gray (10YR 6/1) loamy fine sand; single grained; few fine roots; slightly alkaline.
TYPE LOCATION: Panola County, Texas; 5 miles east of east loop around Carthage on Hills Lake Road; 8 miles south on dirt road; 2 miles west of oil well; 125 feet north of pipeline.
RANGE IN CHARACTERISTICS:
Solum thickness: 40 to more than 80 inches; typically, when the solum is less than 60 inches thick the soil is underlain by a sandy 2C horizon.
Clay content in the Control Section: 20 to 35 percent
Redoximorphic features: Iron accumulations in shades of brown, yellow or red are in all layers below the A horizon.
Other distinctive soil features: The combined thickness of the epipedon is 6 to 20 inches. About 20 to 40 percent of the sand fraction is coarser than very fine sand. The soil is dry in the moisture control section for 50 cumulative days or more in most years.
Concentrated minerals: Salinity ranges from nonsaline to slightly saline and the sodium adsorption ratio ranges from 2 to 10 throughout the argillic horizon.
A horizon:
Color--Hue of 10YR, value of 3 to 5, and chroma of 1 or 2
Redoximorphic features--None
Texture--Fine sandy loam, very fine sandy loam, loam or silt loam
Other features--None
Reaction--Very strongly acid to moderately acid, unless limed
Eg horizon:
Color--Hue of 10YR, value of 4 to 8, and chroma of 1 or 2
Redoximorphic features--Iron accumulations in shades of brown or yellow, and iron depletions in shades of gray range from few to common.
Texture--Fine sandy loam, very fine sandy loam, loam or silt loam
Other features--None
Reaction--Very strongly acid to moderately acid, unless limed
Btg/E horizon:
Color--Hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 1 or 2 in the Bt parts; and hue of 10YR, value of 5 to 8, and chroma of 1 or 2 in the E parts. The faces of some peds have darker coats than these colors.
Redoximorphic features--Iron accumulations in shades of brown, yellow or red range from few to many.
Texture--Loam, sandy clay loam or clay loam
Other features--The E parts consist of albic material in the form of vertical intrusions, streaks or pockets that occupy 5 to about 35 percent of the horizon. Some subhorizon at least 2 inches in thickness has more than 15 percent intrusions of albic materials however.
Reaction--Very strongly acid to moderately acid
BCtg/E horizon: (where present)
Color--Hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 1 or 2 in the BCt parts; and hue of 10YR, value of 5 to 8, and chroma of 1 or 2 in the E parts. The faces of some peds have darker coats than these colors.
Redoximorphic features--Iron accumulations in shades of brown, yellow or red range from few to many.
Texture--Loam, sandy clay loam or clay loam
Other features--The E parts consist of albic material in the form of vertical intrusions, streaks or pockets that occupy 5 to about 35 percent of the horizon.
Reaction--Very strongly acid to slightly alkaline
Btg or BCtg horizon: (where present)
Color--Hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 1 or 2. The faces of some peds have darker coats than these colors.
Redoximorphic features--Iron accumulations in shades of brown, yellow or red range from few to many.
Texture--Loam, sandy clay loam or clay loam
Other features--Streaks of albic materials range from none to few.
Reaction--Strongly acid to slightly alkaline
2C or Cg horizon: (where present)
Color--Hue of 10YR or 2.5Y, value of 5 to 7, and chroma of 1 to 4
Redoximorphic features--None to common streaks and iron accumulations in shades of yellow, brown or red, or the layer is variegated with these colors.
Texture--Loamy fine sand or fine sandy loam, or it is stratified with these textures. The average clay content ranges from 3 to about 12 percent.
Other features--None
Reaction--Strongly acid to slightly alkaline
COMPETING SERIES: These are the Colita, Vimville, and Waller series in the same family, and the Derly, Evadale, Gessner, Lelavale, Mollco, and Wrightsville series in closely related families. Colita soils have a paralithic contact at a depth of 40 to 60 inches. Derly, Evadale, and Wrightsville soils have a fine textured control section. Gessner soils have a coarse-loamy control section. Lelavale soils are in closed depressions, are ponded from October through June in normal years, and are in a semiactive activity class. Mollco soils are ponded for more than 4 months in normal years and are in a superactive activity class. Vimville soils have a glossic horizon that extends to more than 60 inches deep and they do not have a substratum with less than 15 percent clay. Waller soils have an albic horizon more than 14 inches thick, and an ochric epipedon more than 20 inches thick.
GEOGRAPHIC SETTING: Mollville soils are typically on first level terraces. However, they are on third or higher level terraces on some larger river systems. Slopes are less than 1 percent with a plain or concave surface. The soils formed in sandy and loamy alluvial sediments. The surfaces typically have been reworked by wind. The climate is humid temperate. The mean annual precipitation ranges from 42 to 56 inches, mean annual temperature is from 64 to 68 degrees F., frost free days range from 220 to 260, the elevation ranges from 150 to 450 feet above sea level, and Thornthwaite P-E index exceeds 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the closely related Wrightsville series, and the Attoyac, Bernaldo, Besner, Bienville, Bonn, Cart, Derly, Hainesville, Latch, Spurger, and Verdun series. Attoyac soils are above on slightly higher terrace positions and they are well drained. Bernaldo soils are on similar or slightly higher terrace positions and are well drained. Besner and Cart soils are on adjoining mounds and are well drained. Bienville, Latch, and Hainesville soils are on slightly higher terrace positions adjoining low ridges or mounds, and they have a sandy surface layer. Bonn and Verdun soils are on similar positions and have a natric horizon. Derly and Wrightsville soils are on similar positions and have a fine textured control section. Spurger soils are on similar positions, are moderately well drained, and have a clayey control section.
DRAINAGE AND PERMEABILITY: Poorly drained; low rate of runoff; slow permeability. The soil is ponded during the winter and spring mainly for brief to long durations after heavy or prolonged rainfall. A saturated zone with its upper boundaty at 0 to 12 inches is perched above the Btg horizon for brief to long periods for a cumulative duration of 2 to 4 months during normal years.
USE AND VEGETATION: Mainly hardwood forest of water oak, sweetgum, blackgum, and post oak.
DISTRIBUTION AND EXTENT: Western Coastal Plain (MLRA 133B) in eastern Texas and possibly Arkansas, Louisiana, and Oklahoma. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Panola County, Texas; 1971.
REMARKS: Mollville soils that are on the Sabine River Terrace, mainly on the first or second terrace level, have a sandy 2C horizon. Mollville soils on third and higher level terraces, and on some other terrace systems in the western parts of MLRA 133B typically have a loamy subsoil to a depth of 80 inches. A loamy substratum phase was recognized for the soils that do not have a sandy 2C horizon. It was decided in 2002 that a separate series (Vimville?) is needed for the loamy substratum phase for all future updates in MLRA 133B. The allowance for loamy textures with up to 35 percent clay in the 2C horizon was removed from the Mollville series range in characteristics in 2002. The series was updated in 2004 to allow redox features in the Eg horizon.
Diagnostic horizons and features recognized in the type location pedon include:
Ochric epipedon -- 0 to 11 inches (A and Eg horizons).
Albic horizon ---- 5 to 11 inches (Eg horizon).
Glossic horizon -- 11 to 23 inches (Btg/E1 horizon).
Argillic horizon - 11 to 54 inches (Btg/E, Btg, and BCtg horizons).
Intrusions of albic material - 11 to 47 inches (Btg/E and Btg horizons).
ADDITIONAL DATA: Partial Data by TAMU Characterization Lab (S82TX-365- 2) from type location indicate 11 percent exchangeable sodium percentage (ESP).