LOCATION BRIMSTONE LAEstablished Series
TAXONOMIC CLASS: Fine-silty, siliceous, superactive, thermic Glossic Natraqualfs
TYPICAL PEDON: Brimstone silt loam on a 0.2 percent smooth slope in a cultivated field.(Colors are for moist soil).
Ap--0 to 6 inches; dark grayish brown (10YR 4/2) silt loam; weak
fine granular structure; friable; many fine roots; common fine pores; few dark yellowish brown stains in pores and on faces of peds; very strongly acid ; abrupt smooth boundary. (4 to 7 inches thick)
E--6 to 16 inches; grayish brown (10YR 5/2) silt loam; common
medium faint yellowish brown (10YR 5/4) mottles; weak very coarse prismatic structure; firm, brittle; few fine roots; common fine pores; few patches and streaks of light gray silt; common medium strong brown stains on faces of prisms; medium acid; clear irregular boundary. (6 to 24 inches thick)
E/Btng--16 to 27 inches; about 60 percent tongues of light brownish gray (10YR 6/2) silt loam; firm, brittle (E); about 40 percent grayish brown (10YR 5/2) silt loam; firm, brittle (Bt); common moderately faint yellowish brown (10YR 5/4) mottles; weak coarse prismatic structure; friable; few fine roots; distinct discontinuous clay films on faces of peds; few fine black concretions; common dark gray clay bands and few streaks and pockets of light gray silt in E material; neutral; gradual irregular boundary. (0 to 13 inches thick)
Btng/E--27 to 39 inches; about 65 percent grayish brown (10YR 5/2) silty clay loam (Bt); common medium faint yellowish brown (10YR 5/4) mottles; weak coarse prismatic structure; friable; few fine roots; few discontinuous clay films on faces of peds; about 35 percent light brownish gray (10YR 6/2) silt loam; massive, firm, brittle (E); few medium and fine black concretions; mildly alkaline; gradual irregular boundary. (6 to 16 inches thick)
Btng1--39 to 52 inches; grayish brown (10YR 5/2) silty clay loam; common medium faint yellowish brown (10YR 5/6) mottles; weak coarse prismatic structure parting to weak medium subangular blocky; few fine pores; thin discontinuous clay films on faces of peds; few fine and medium black concretions; few streaks of light gray silt; few medium and coarse calcium carbonate concretions; mildly alkaline; gradual wavy boundary. (10 to 24 inches thick)
Btng2--52 to 70 inches; light olive gray (5Y 6/2) silty clay loam; common medium prominent strong brown (7.5YR 5/8) mottles; weak coarse subangular blocky structure; firm; thin patchy clay films on faces of peds; few medium calcium carbonate concretions; moderately alkaline.
TYPE LOCATION: Calcasieu Parish, Louisiana; 1 mile east of Gillis; 240 feet west of irrigation canal; NE1/4NE1/4, sec. 16, T. 8 S., R. 8 W.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 40 to 100 inches. Exchangeable sodium percentage ranges from 15 to 30 within the upper 6 inches of the natric horizon or within 16 inches of the soil surface. Exchangeable sodium saturation decreases with depth and its typically less than 15 percent below depths of 52 inches.
The Ap horizon has hue of 10YR, value of 3 to 5, and chroma of 1 or 2. Texture is silt loam or very fine sandy loam. Reaction ranges from strongly acid to mildly alkaline.
The E horizon has hue of 10YR or 2.5Y, value of 5 or 6, and chroma of 1 or 2. Texture is silt loam or very fine sandy loam. Reaction ranges from medium acid to moderately alkaline. Tongues of the E horizon extend into the Bt horizons. Dark gray discontinuous clay bands occur in some pedons.
The B horizon has hue of 10YR, 2.5Y, or 5Y, value of 5 or 6, and chroma of 1 or 2. Mottles are in shades of brown or gray. Texture is silt loam or silty clay loam. Reaction ranges from neutral to moderately alkaline. Calcium carbonate concretions range from none to common. Some pedons have BC horizons with characteristics similar to the B horizons.
COMPETING SERIES: There are no other series in this family. Basile, Bonn, Calhoun, Deerford, Diboll, Foley, Fountain, Frost, Guyton, Hillemann, Lafe, McCrory, Peoria, Rosella, Verdun, and Wing series are in similar families. Basile, Calhoun, Fountain, Frost, and Guyton soils lack natric horizons. Bonn, Diboll, and Verdun soils have mixed mineralogy. Deerford, Foley, Hilleman, McCrory, Peoria, and Rosella soils have less than 15 percent exchangeable sodium in the upper part of the B horizon. Lafe and Wing soils have chroma of 3 or more throughout the B horizon.
GEOGRAPHIC SETTING: Brimstone soils are on broad flats of late Pleistocene age terraces. Slope ranges from 0 to 1 percent. The soil formed in loamy alluvium. The mean annual temperature is 68 degrees F, and the mean annual rainfall is about 53 inches near the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Basile and Guyton soils. Other associated soils are the Caddo, Glenmora, Kinder, Messer, and Vidrine soils. The competing Basile and Guyton soils are at lower elevations in local stream floodplains. Caddo, Glenmora, and Kinder soils are on slightly higher parts of the landscape, are more acid, and lack natric horizons. Messer and Vidrine soils are on circular mounds, are more acid, and lack natric horizons.
DRAINAGE AND PERMEABILITY: Poorly drained; runoff is slow; permeability is slow. A seasonal high water table is at depths of 0 to 1.5 feet below the surface from December through April.
USE AND VEGETATION: Most of the Brimstone soil is in woodland, mainly pine and mixed hardwood. A smaller acreage is in cropland. Rice and soybeans are the main crops.
DISTRIBUTION AND EXTENT: South Louisiana and possibly southeast Texas. The soils of this series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Calcasieu Parish, Louisiana 1983.
REMARKS: These soils were formerly included in the Bonn series LAES characterization data available on sample #S78LA-19-7(1-7).
Diagnostic horizons and other features recognized in this pedon are:
Ochric epipedon: 0 to 16 inches, Ap and E horizons.
Albic horizon: 6 to 16 inches, E horizon
Interfingering of albic material into the natric horizon: 16 to 27 inches, E/Btng horizon.
Natric horizon: 16 to 70 inches.