LOCATION GALLION LA+AR OKEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Typic Hapludalfs
TYPICAL PEDON: Gallion silt loam - cultivated field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 10 inches; brown (7.5YR 4/2) silt loam; weak fine and medium granular structure; friable; many fine pores; moderately acid; abrupt smooth boundary. (4 to 14 inches thick)
Bt1--10 to 22 inches; yellowish red (5YR 4/6) silty clay loam; compound weak coarse prismatic and moderate medium and coarse subangular blocky structure; firm, hard; many very fine pores; few faint dark reddish brown (5YR 3/6) clay films, mostly on vertical prism faces and in root holes; slightly acid; gradual smooth boundary. (6 to 16 inches thick)
Bt2--22 to 33 inches; yellowish red (5YR 4/6) silt loam; compound weak coarse prismatic and weak coarse subangular blocky structure; firm, hard; many very fine pores; common faint dark reddish brown (5YR 3/6) clay films on major peds and in root channels and pores; few fine black Fe-Mn concretions; slightly acid; clear smooth boundary. (6 to 16 inches thick)
BC--33 to 44 inches; yellowish red (5YR 4/6) silt loam; weak medium and coarse subangular blocky structure; friable, slightly hard; common faint clay films in pores; few fine black Fe-Mn concretions; mildly alkaline; clear wavy boundary. (6 to 20 inches thick)
C1--44 to 49 inches; reddish brown (5YR 4/4) very fine sandy loam, with lenses of loam or silt loam about 2 inches thick; weak medium and coarse subangular blocky structure; friable; many fine pores; slightly acid; abrupt smooth boundary.
C2--49 to 60 inches; yellowish red (5YR 4/6) silt loam and very fine sandy loam in 2 to 3 inch strata; weak medium subangular blocky structure; very friable; many fine pores; common fine lime concretions; calcareous; moderately alkaline.
TYPE LOCATION: Red River Parish, Louisiana; about 2.7 miles west of U. S. Highway 84 on farm road at Westdale to a point 300 feet west of Watson Bayou and 400 feet north of road, NW1/4NE/4, sec. 29, T. 14 N., R. 11 W.
RANGE IN CHARACTERISTICS: Solum thickness is 40 to 60 inches.
The A or Ap horizon has hue of 7.5YR or 10YR, value of 4 or 5, and chroma of 2 to 4. Texture is very fine sandy loam, silt loam or silty clay loam. Reaction ranges from moderately acid to neutral.
The Bt horizon has hue of 5YR or 7.5YR, value of 3 to 5, and chroma of 3 to 5. Texture is silt loam, clay loam, loam or silty clay loam. Reaction ranges from medium acid to mildly alkaline.
The BC horizon has the same color range as the B2t horizon. Texture is very fine sandy loam, loam, silt loam, clay loam, or silty clay loam. Reaction ranges from moderately acid to moderately alkaline. Carbonate concretions are present in the BC horizon of some pedons.
The C horizon has the same color and textural range as the B horizon. It is typically stratified. Reaction ranges from slightly acid to moderately alkaline. Carbonate concretions are present in the C horizon of some pedons.
COMPETING SERIES: These are the Dubbs, Memphis, Rilla and Siwell series in the same family and the Coushatta and Dexter series in similar families. Dubbs and Memphis soils have Bt horizons with hues of 7.5YR and 10YR. Rilla Soils are more acid and have prominent silt coatings on major ped faces. Siwell soils have clayey 2C horizons. Coushatta soils are more alkaline and lack argillic horizons. Dexter soils are more acid and have less than 60 percent base saturation.
GEOGRAPHIC SETTING: Gallion soils are on nearly level to gently sloping natural levees along the Red River and the present and abandoned channels of the Arkansas River. Slope gradients range from 0 to 5 percent. The soils formed in reddish silty alluvium of mixed mineralogy. The climate is warm and humid. Mean annual rainfall ranges from 38 to 60 inches and mean annual temperature ranges from 57 to 66 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Buxin, Caspiana, Latanier, and Moreland series. Buxin and Moreland soils are clayey throughout. Caspiana soils have a mollic epipedon. Latanier soils have clayey over loamy control sections.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability.
USE AND VEGETATION: Most areas are cleared and used for cotton, soybeans, corn, or pasture. Native vegetation was mixed hardwood forest.
DISTRIBUTION AND EXTENT: Louisiana, Arkansas, and possibly eastern Oklahoma and northeastern Texas. This series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Little Rock, Arkansas
SERIES ESTABLISHED: Bossier Parish, Louisiana; 1959.
REMARKS: These soils formerly were included in the Dexter series.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon...................0 to 10 inches (Ap)
Argillic horizon............10 to 44 inches (Bt1,Bt2)