LOCATION CHATOM                  AL

Established Series
SP, JLL; GRB
12/2014

CHATOM SERIES


The Chatom series consists of very deep, moderately well drained, moderately slow to slowly permeable soils on upland ridges and side slopes of dissected high marine terraces of the Southern Coastal Plain. They formed in thick beds of loamy and clayey Miocene-age sediments. Near the type location, the mean annual precipitation is about 60 inches and the mean annual temperature is about 66 degrees. Slopes range from 2 to 15 percent.

TAXONOMIC CLASS: Fine-loamy, siliceous, subactive, thermic Aquic Hapludults

TYPICAL PEDON: Chatom fine sandy loam, on a gently sloping ridge under a mixed canopy of managed pines and hardwoods at an elevation of approximately 145 feet above sea level (Colors are for moist soil).

Ap--0 to 3 inches; brown (10YR 4/3) fine sandy loam; weak fine blocky structure; very friable, nonsticky, nonplastic; many fine, common medium and few coarse roots; about 7 percent, by volume, pebbles; very strongly acid; clear smooth boundary. (2 to 12 inches thick)

E--3 to 11 inches; light yellowish brown (10YR 6/4) very fine sandy loam; weak medium subangular blocky structure; very friable, common fine and medium, few coarse roots; about 2 percent, by volume, pebbles; strongly acid; clear smooth boundary. (0 to 15 inches thick)

Bt1--11 to 27 inches; yellowish brown (10YR 5/8) sandy clay loam; moderate medium subangular blocky structure; friable, common fine, medium and coarse roots; common medium distinct strong brown (7.5YR 5/6) and few medium prominent yellowish red (5YR 5/6) clay films on faces of peds; strongly acid; clear wavy boundary.

Bt2--27 to 44 inches; brownish yellow (10YR 6/6) sandy clay loam; strong coarse blocky structure parting to moderate medium subangular blocky; firm; few fine, medium and coarse roots; common medium distinct yellowish brown (10YR 5/6) clay films on faces of peds; many sand grains coated and bridged with clay; common medium distinct light brownish gray (10YR 6/2) areas iron and clay depletions; common medium prominent yellowish red (5YR 4/6) masses of iron accumulations; very strongly acid; gradual irregular boundary.

Bt3--44 to 73 inches; 40 percent light gray (10YR 7/2), 30 percent brownish yellow (10YR 6/6), 20 percent pale brown (10YR 6/3) and 10 percent red (2.5YR 4/8) sandy clay loam; strong coarse angular blocky structure parting to moderate medium subangular blocky; firm; few fine and coarse roots; common distinct yellowish brown (10YR 5/6) clay films on faces of peds; many sand grains coated and bridged with clay; the areas of light gray and pale brown are iron depletions and the areas of brownish yellow and red are iron accumulations; very strongly acid; gradual irregular boundary. (Combined thickness of the Bt horizons ranges from 30 to more than 60 inches)

2B/C--73 to 80 inches; 60 percent light gray (10YR 7/2) clay, weak coarse prismatic structure parting to strong medium and coarse angular blocky; very firm (B) and 25 percent brownish yellow (10YR 6/8), 7 percent strong brown (7.5YR 5/6), 5 percent red (2.5YR 4/6) and 3 percent dark reddish brown (2.5YR 3/4) sandy clay loam; massive; very firm (C); the areas of light gray are iron depletions and the areas of brownish yellow, strong brown, red and dusky red are iron accumulations; very strongly acid.

TYPE LOCATION: Washington County, Alabama; near the southeast corner of Chatom city limit; about 75 feet south and 1,250 feet west of the northeast corner of Section 36; T.6N., R. 3 W.; USGS Rutan topographic quadrangle; latitude 31 degrees 26 minutes 59 seconds N.; longitude 88 degrees 13 minutes 53 seconds W.

RANGE IN CHARACTERISTICS: Solum thickness is more than 60 inches. Depth to seasonal high saturation ranges from 22 to 30 inches. Reaction ranges from very strongly acid or strongly acid throughout except where the surface layer has been limed.

The A or Ap horizon has hue of 10YR, value of 3 or 4, and chroma of 2 to 3. Texture is fine sandy loam or sandy loam.

The E horizon, present in most pedons, has hue of 10YR, value of 5 or 6, and chroma of 3 to 6. Texture is loamy fine sand, very fine sandy loam, fine sandy loam or sandy loam.

The upper part of the Bt horizon has hue of 7.5YR or 10YR, value of 5 to 7, and chroma of 3 to 8. Redoximorphic features in shades of brown, yellow and red range from none to common. Texture is loam, sandy clay loam or clay loam.

The lower part of the Bt horizon has hue of 7.5YR to 2.5Y, value of 5 to 7, and chroma of 3 to 8; or it has no dominant matrix color and is multicolored in shades of brown, yellow, red and gray. Redoximorphic features in shades of yellow, brown, red and gray range from few to many. Texture is loam, sandy clay loam, clay loam or clay.

The 2B/C or 2B/Cg horizon, where present, has hue of 7.5YR to 2.5Y, value of 4 to 7, and chroma of 1 to 6; or it has no dominant color and is multicolored in shades of brown, yellow, red and gray. Redoximorphic features in shades of brown, yellow, red and gray range from few to many. Texture is (B) sandy clay loam, clay loam, sandy clay or clay and (C) sandy loam, loam, sandy clay loam, or sandy clay with some small pockets and thin strata of clay.

The 2C or 2Cg horizon, where present, has similar range of colors as the 2B/C horizon. Texture ranges from sandy loam to clay in stratified layers.

COMPETING SERIES: The Slagle series is the only known soil in the same family. The Eunola series is in a closely related family. Slagle and Eunola soils are parallel to the Atlantic Coast and receive considerably less annual precipitation. In addition, Eunola soils are in a semiactive cation exchange activity class.

GEOGRAPHIC SETTING: Chatom soils are on upland ridges and side slopes of the Southern Coastal Plain. They formed in thick beds of loamy and clayey Miocene-age sediments. The climate is humid subtropical. Slopes range from 2 to 15 percent. The average annual precipitation ranges from 58 to 62 inches and the average annual temperature ranges from 62 to 70 degrees.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fruitdale, Gritney, Irvington, Maubila, Rutan and Toinette soils. The well-drained Fruitdale soils are on slightly higher positions. Gritney and Maubila soils have clayey subsoils. The well-drained Rutan soils are coarse-loamy. The somewhat poorly drained Toinette soils have sandy surface and subsurface layers 20 to 40 inches in thickness.

DRAINAGE AND PERMEABILITY: Moderately well drained; moderately slow permeability in the upper solum and moderately slow to slow in the underlying material.

USE AND VEGETATION: Most areas of Chatom soils are used for planted pine. Some areas are used for cropland and pasture. Native vegetation consists of loblolly pine, longleaf pine, sweetgum, red maple, southern red oak, water oak, yellow-poplar and hickory.

DISTRIBUTION AND EXTENT: Southern Coastal Plain of west Alabama and possibly Mississippi and west Florida. This series is of small known extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama.

SERIES PROPOSED: Washington County, Alabama, 2010.

REMARKS: Diagnostic horizons and soil characteristics recognized in this pedon:

Ochric epipedon - the zone from 0 to 11 inches (Ap and E horizons).

Argillic horizon - the zone from 11 to 73 inches (Bt1, Bt2 and Bt3 horizons).

Aquic conditions - the soil has redox depletions and masses within the upper 27 inches of the argillic horizon, with periodic saturation and reduction at some time during the year.

The laboratory data supports a Hapludult since there is a 29% clay decrease between 12 and 45 inches. The clay content in the 2B/C horizon was not derived from the overlying Bt horizons.

ADDITIONAL DATA: Laboratory characterization data is from the Auburn University Agronomy and Soils Department. Characterization laboratory data is available for the for the typical pedon 10AL-129-004(1-6).

Chatom soils are in MLRA 133A.


National Cooperative Soil Survey
U.S.A.