LOCATION ROBERTSDALE AL+FL GA
Established Series
Rev. MGM: LFR, SP, GRB
09/2013
ROBERTSDALE SERIES
The Robertsdale series consists of very deep, somewhat poorly drained, slowly permeable soils on nearly level or slightly depressed upland areas of the Southern Coastal Plain Major Land Resource Area (133A). They formed in loamy marine and fluviomarine sediments. Near the type location, the average annual temperature is about 67 degrees F., and the average annual precipitation is about 67 inches. Slopes range from 0 to 2 percent.
TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, thermic Plinthaquic Paleudults
TYPICAL PEDON: Robertsdale fine sandy loam, in an area of nearly level cropland (Colors are for moist soil).
Ap--0 to 6 inches; very dark gray (10YR 3/1) fine sandy loam; weak medium platy structure parting to weak medium granular; friable; common fine iron concretions; moderately acid; abrupt smooth boundary. (2 to 9 inches thick)
EBc--6 to 12 inches; light yellowish brown (2.5Y 6/4) fine sandy loam; weak coarse subangular blocky structure; friable; common fine iron concretions; common faint clay bridging of sand grains; few small areas of clean sand grains; few fine faint yellowish brown (10YR 5/8) and strong brown (7.5YR 5/6) masses of iron accumulation; very strongly acid; clear wavy boundary. (3 to 12 inches thick)
Btc--12 to 21 inches; pale brown (10YR 6/3) loam; weak coarse subangular blocky structure; friable; common fine and medium iron concretions; few faint clay films on ped faces; areas in shades of brown have sand grains bridged with clay; many distinct clean sand grains in areas having shades of gray; about 4 percent, by volume, plinthite; common medium distinct strong brown (7.5YR 5/6) and few medium faint yellowish brown (10YR 5/8) masses of iron accumulation; common medium distinct light gray (2.5Y7/2) iron depletions; strongly acid; gradual wavy boundary. (3 to 14 inches thick)
Btvg1--21 to 29 inches; light gray (2.5Y 7/2) sandy clay loam; coarse prismatic structure, parting to weak coarse subangular blocky; firm; common fine and medium iron concretions; few faint clay films on faces of peds; sand grains strongly bridged with clay; about 20 percent, by volume, plinthite nodules; many medium and coarse distinct yellowish brown (10YR 5/6) masses of iron accumulation; strongly acid; gradual wavy boundary.
Btvg2--29 to 43 inches; light gray (2.5Y 7/2) sandy clay loam; coarse prismatic structure parting to weak coarse blocky; firm; common fine vesicular pores lined with clay; common fine and medium hard iron concretions; few faint clay films on faces of peds; few uncoated sand grains in the light gray matrix; about 15 percent, by volume, plinthite nodules; many medium distinct yellowish brown (10YR 5/8) masses of iron accumulation; common medium faint gray (10YR 6/1) iron depletions; strongly acid; clear wavy boundary.
Btvg3--43 to 68 inches; 40 percent yellowish brown (10YR 5/6), 40 percent red (2.5YR 4/8) and 20 percent light gray (10YR 7/1) sandy clay loam; weak coarse prismatic parting to coarse platy structure parting to weak medium blocky; very firm; seams between prisms filled with light gray (10YR 7/1) fine sandy loam; many distinct vesicular pores lined with clay; common medium and coarse iron concretions; few faint clay films on faces of peds; about 10 percent, by volume, plinthite nodules; the areas of yellowish brown and red are iron accumulations and the areas of light gray are iron and clay depletions; moderately acid; clear wavy boundary. (Combined thickness of the Btvg horizons ranges from 35 to more than 76 inches in thickness)
Cg--68 to 74 inches; 34 percent red (10R 4/8), 33 percent brownish yellow (10YR 6/8) and 33 percent light gray (10YR 7/1) light clay loam; massive; friable; the areas in red and brownish yellow are iron accumulations and the areas in light gray are iron depletions; moderately acid.
TYPE LOCATION: Baldwin County, Alabama. Approximately 1.0 mile south and 1 mile east of the south edge of Robertsdale, about 230 feet north on gravel road, and about 25 feet east the of center of the road in the SW1/4, SW1/4, Sec. 8, T. 6 S., R. 4 E.
RANGE IN CHARACTERISTICS: Solum thickness and depth to bedrock is more than 60 inches. Reaction ranges from very strongly acid to moderately acid except where the surface has been limed. Silt content in the control section ranges from 20 to 50 percent.
The A or Ap horizon has hue of 10YR, value of 2 through 4, and chroma 1 or 2. Redoximorphic features in shades of gray or brown range from none to common. Iron concretions up to 7.5 cm in diameter range from 4 to 12 percent, by volume. Texture is fine sandy loam or loam.
The EB and Btc horizons have hue of 10YR or 2.5Y, values 5 or 6, and chroma 3 through 6. Redoximorphic features in in shades of gray and brown range from few to many. Iron concretions up to 7.5 cm in diameter range from 4 to 12 percent, by volume. Texture is loam, sandy clay loam or clay loam.
The Btc horizon has hue of 10YR or 2.5Y, value of 5 or 6 and chroma of 3 to 6. Redoximorphic features in shades of yellow, brown and gray range from few to many. The amount of plinthite ranges from 0 to 4 percent, by volume. Iron concretions up to 2.5 cm in diameter make up 5 to 25 percent, by volume. Texture is loam, sandy clay loam, silty clay loam or clay loam.
The Btcg horizon has hue of 10YR or 2.5Y, value of 5 or 6 and chroma of 1 or 2. Iron accumulations in shades of yellow, brown and red range from few to many. Some pedons have no dominant color and are multicolored in shades of gray, yellow, brown, and red. The amount of plinthite ranges from 0 to 4 percent, by volume. Iron concretions up to 2.5 cm in diameter make up 5 to 25 percent, by volume. Texture is loam, sandy clay loam, silty clay loam or clay loam.
The Btvg horizon has hue of 10YR to 5Y, value of 4 to 7, and chroma of 1 or 2. Iron accumulations in shades of yellow, brown and red range from common to many. Some pedons have no dominant color and are multicolored in shades of gray, yellow, brown and red. Content of plinthite ranges from 5 to 30 percent, by volume. Iron concretions up to 2.5 cm in diameter range from 5 to 25 percent, by volume. Texture is sandy clay loam, loam, or clay loam.
The Btvx horizon, where present, is generally below a depth of 60 inches and has the same range of colors and texture as the Btvg horizon.
The Cg horizon, where present, has no dominant color and is variegated in shades of red, brown, yellow and gray. Texture is sandy clay loam, clay loam or sandy clay.
COMPETING SERIES: The
Clarendon series is the only known competing series. The
Saucier series is in a closely related family. The moderately well drained Clarendon soils are on higher positions and have less than 5 percent hard iron concretions and less than 20 percent silt in the control section. The moderately well drained Saucier soils are on higher positions and have less than 5 percent hard iron concretions in the control section.
GEOGRAPHIC SETTING: Robertsdale soils are on nearly level and slightly depressed areas of the Southern Coastal Plain. They formed in loamy marine and fluviomarine sediments. The climate is humid subtropical. Slopes range from 0 to 2 percent. Near the type location, the mean annual air temperature is about 67 degrees F., and the average annual precipitation is about 67 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the
Atmore,
Bama,
Benndale,
Escambia,
Grady,
Harleston,
Irvington,
Malbis and
Poarch series. The poorly drained Atmore soils are on similar to lower positions and have coarse-loamy control sections. The well drained Bama and Benndale soils are on higher adjacent positions and have less than 5 percent, by volume, plinthite. The well drained Bama and Benndale soils are on higher positions and have less than 5 percent, by volume, plinthite in their control sections. In addition, Bama soils have red subsoils. Escambia soils are on similar positions and have coarse-loamy subsoils. Grady soils are in similar to lower positions have less than 5 percent plinthite, by volume and have clayey control sections. The moderately well drained Harleston soils are on higher positions have less than 5 percent, by volume, plinthite and have coarse-loamy control sections. The moderately well drained Irvington soils are on higher positions. The moderately well and well drained Malbis and Poarch soils are on higher positions. In addition, Poarch soils have coarse-loamy control sections.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow permeability.
USE AND VEGETATION: Most areas of Robertsdale soils are used for cropland. Some areas are used for pasture and woodland. Native vegetation consists of slash pine, longleaf pine, loblolly pine, sweetgum along with other hardwoods with an understory dominated by gallberry and wiregrass.
DISTRIBUTION AND EXTENT: Alabama, Florida, Georgia, Mississippi, Texas, and possibly Louisiana. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama.
SERIES ESTABLISHED: Baldwin County, Alabama; 1961.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - the zone from 0 to 12 inches (Ap and EBc horizons).
Argillic horizon - the zone from 12 to 68 inches (Btc, Btvg1, Btvg2 and Btgv3 horizons).
Plinthic horizon - the zone from 21 to 68 inches (Btvg1, Btvg2 and Btgv3 horizons).
Aquic feature - Robertsdale soils are saturated to near the surface in late winter and the spring.
Robertsdale soils were formerly identified as a flat phase within the Irvington series and placed in the Red-Yellow Podzolic great soil group with a fragipan. The classification is changed to Plinthaquic Paleudults. Silt content is specified as being over 20 percent.
Robertsdale soils are in MLRA 133A.
ADDITIONAL DATA: There is no record of soil laboratory data for the Robertsdale series in the database at this time.
National Cooperative Soil Survey
U.S.A.