LOCATION DUBACH LAEstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, thermic Typic Paleudults
TYPICAL PEDON: Dubach fine sandy loam--pasture/hayland, formerly cultivated. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 4 inches; brown (10YR 4/3) very fine sandy loam; weak fine granular structure; very friable; few fine pores; many fine roots; strongly acid; clear smooth boundary. (3 to 8 inches thick)
E1--4 to 8 inches; yellowish brown (10YR 5/4) very fine sandy loam; weak fine subangular blocky structure; very friable; common fine pores; common fine roots;medium acid; clear smooth boundary.
E2--8 to 12 inches; light yellowish brown (10YR 6/4) very fine sandy loam; weak fine subangular blocky structure; very friable; many fine and medium pores; few medium roots; slightly acid; gradual smooth boundary. (Combined thickness of the E horizon is 0 to 10 inches thick)
Bt1--12 to 24 inches; strong brown (7.5YR 5/6) loam; moderate medium subangular blocky structure; friable; many medium pores; common fine and medium roots; common distinct clay films on faces of peds; medium acid; gradual wavy boundary.
Bt2--24 to 33 inches; strong brown (7.5YR 5/6) loam; weak coarse prismatic structure parting to weak medium subangular blocky; firm; many medium pores; common fine and medium roots; common distinct yellowish red (5YR 4/6) clay films on faces of peds; medium acid; gradual wavy boundary.
Bt3--33 to 43 inches; yellowish brown (10YR 5/8) sandy clay loam; few fine prominent red (2.5YR 4/8) mottles; moderate medium subangular blocky structure; fine; few medium pores; few fine and medium roots; common distinct clay films on faces of peds; strongly acid; gradual wavy boundary. (Combines thickness of the Bt horizon is 15 to 65 inches.)
Btv1--43 to 49 inches; yellowish brown (10YR 5/6) loam; common medium prominent yellowish red (5YR 4/6) and common medium distinct light brownish gray (10YR 6/2) mottles; moderate medium subangular blocky structure; firm, somewhat brittle; common medium pores; few fine roots; common distinct clay films on faces of peds; 3 percent nodules of plinthite; few iron-manganese concretions; few black stains in root channels and pores; very strongly acid; gradual wavy boundary.
Btv2--49 to 60 inches; strong brown (7.5YR 5/6) sandy clay loam; many coarse distinct light brownish gray (10YR 6/2) and common prominent red (2.5YR 4/6) mottles; moderate coarse subangular blocky structure; firm, slightly brittle; few fine pores; few fine roots; common distinct clay films on faces of peds; 3 percent nodules of plinthite; few black stains in abandoned root channels and pores; very strongly acid; clear wavy boundary. (Combined thickness of the Btv horizon is 10 to 48 inches.)
B't--60 to 80 inches; yellowish brown (10YR 5/6) sandy clay loam; common medium distinct light brownish gray (10YR 6/2) and common medium distinct strong brown (7.5YR 5/6) mottles; moderate coarse subangular blocky structure; firm, slightly brittle; common medium pores; few medium roots; common distinct clay films on faces of peds; very strongly acid. (0 to 25 inches thick)
TYPE LOCATION: Lincoln Parish, Louisiana; approximately 3.7 miles southwest of Hico; 3,200 feet north, 400 feet east of the southwest corner sec. 25, T. 20 N., R. 4 W.
RANGE IN CHARACTERISTICS: Solum thickness exceeds 80 inches. Calcium content at a depth of 50 inches typically is 0.4 to 1.0 meq/100gm but ranges from less than 0.1 to 2meq/100gm.
The A or Ap horizon has hue of 7.5YR, value of 4 or 5, and chroma of 2 to 4, or hue of 10YR, value of 3 to 5, and chroma of 2 to 4. It is fine sandy loam, loam, or sandy loam and is medium acid or strongly acid.
The E horizon, where present, has hue of 10YR, value of 5 or 6, chroma of 3 to 6. Texture is very fine sandy loam, fine sandy loam, or sandy loam. Reaction is medium acid or strongly acid.
The Bt horizon has hue of 7.5YR or 10YR, value of 5 or 6, chroma of 4 to 8. Texture is loam, sandy clay loam, or clay loam. Reaction is strongly acid or very strongly acid.
The Btv horizon has hue of 7.5YR or 10YR, value of 5 or 6, chroma of 4 to 8. Mottles are in various shades of brown, red, and gray. Nodules of plinthite, by volume, are less than 5 percent. Texture is loam, sandy clay loam, or clay loam. Reaction is strongly acid or very strongly acid.
The B't horizon, where present, has hue of 10YR or 2.5Y, value of 5 or 6, chroma of 4 to 8. Mottles are in shades of brown, red, and gray. Texture is sandy clay loam or clay loam. Reaction is strongly acid or very strongly acid.
COMPETING SERIES: These are the Addielou, Allen, Avilla, Bama, Etowah, Holston, Ironcity (T), Leesburg, Lytle, Minvale, Nella, Noboco, Octavia, Pikeville, Ruston, and Warnock. Addielou has an ochric epipedon more than 20 inches thick. Allen, Avilla, Bama, Etowah, Lytle, Pikeville, and Ruston soils have hue of 5YR or redder in the Bt horizon. Holston, Ironcity, Minvale, and Octavia soils have fragments of sandstone and/or chert in the Bt horizon. Leesburg soils have more than 10 percent coarse fragments. Nella soils have base saturation less than 20 percent and cobbles throughout. Noboco soils do not have plintite nodules in the argillic horizon. Warnock soils have a Btx horizon in the lower part of the argillic horizon.
GEOGRAPHIC SETTING: Dubach soils are on stream terraces of drainageways. The slope is commonly convex and ranges from 1 to 5 percent. The soil formed in loamy sediments. The mean annual temperature ranges from about 60 to 70 degrees F, and the mean annual precipitation ranges from about 45 to 60 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: Cahaba, Gurdon, and Sacul soils. Cahaba soils are on similar landscapes at lower elevations, but clay percentages decrease by more than 20 percent from its maximum amount within 60 inches of the soil surface. Gurdon soils are also on similar landscapes at slightly lower elevations and are somewhat poorly drained and are coarse silty. Sacul soils are on higher elevations on adjacent landscapes. Sacul soils have fine textured Bt horizons.
DRAINAGE AND PERMEABILITY: Dubach soils are well drained. Runoff is slow or moderate. Permeability is moderate in the Bt and Btv horizons and moderately slow in the B't horizon. These soils have a water table at a depth of 3.5 to 5 feet below the surface of the soil from December through March in most years.
USE AND VEGETATION: Almost all areas of Dubach soils are in woodland and pastureland. Loblolly pine is the principal commercial tree. Pasture crops are coastal bermudagrass and Pensacola bahiagrass.
DISTRIBUTION AND EXTENT: Dubach soils are moderately extensive in northwest and north central Louisiana and south central Arkansas.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Lincoln Parish, Louisiana, 1991.
REMARKS: These soils were formerly included in the Malbis series. Malbis soils are on higher and older landscapes. Dubach soils have less than 5 percent plinthite nodules.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon............0 to 12 inches (Ap, E1, E2)
Argillic horizon........12 to 70 inches (Bt, Btv, B't)
Plinthite...3 percent plinthite...43 to 60 inches (Btv)