LOCATION SCATLAKE           LA
Established Series
Rev. HLC-JLD-CLN
08/2000

SCATLAKE SERIES


The Scatlake series consists of very deep, very poorly drained, very slowly permeable fluid mineral soils. These soils formed in unconsolidated saline clayey and organic sediments. These soils are in saline marsh areas along the Gulf Coast. Slope ranges from 0 to 0.2 percent.

TAXONOMIC CLASS: Very-fine, smectitic, nonacid, hyperthermic Sodic Hydraquents

TYPICAL PEDON: Scatlake peat--saltwater marsh wildlife refuge.
(Colors are for moist soil unless otherwise stated.)

Oa--0 to 6 inches; very dark gray (10YR 3/1) peat; about 75 percent fiber, about 50 percent rubbed; about 50 percent mineral; many live roots; moderately saline; moderately alkaline; gradual smooth boundary. (0 to 15 inches thick)

A--6 to 12 inches; very dark gray (5Y 3/1) mucky clay; massive; about 25 percent coarse fibers and roots; very fluid, flows easily between fingers and leaves small residue in hand; moderately saline; moderately alkaline; gradual smooth boundary. (6 to 12 inches thick)

Cg1--12 to 16 inches; dark gray (5Y 4/1) clay, about 5 percent roots and coarse fiber, massive; very fluid, flows easily between fingers and leaves hand empty; moderately saline; moderately alkaline; abrupt smooth boundary.

Cg2--16 to 18 inches; black N 2.5/ muck and gray (5Y 5/1) clay; massive; very fluid, flows easily between fingers and leaves hand empty; moderately saline; moderately alkaline; abrupt smooth boundary.

Cg3--18 to 21 inches; gray (5Y 5/1) clay, massive; very fluid, flows easily between fingers and leaves hand empty; moderately saline; moderately alkaline; abrupt smooth boundary.

Cg4--21 to 80 inches; greenish gray (5GY 6/1) clay, layer less than 1 inch thick of black N 2.5/ muck present; massive; very fluid, flows easily between fingers and leaves hand empty; moderately saline; moderately alkaline. (combined thickness of the Cg horizons is 60 to 75 inches)

TYPE LOCATION: Iberia Parish, Louisiana, Marsh Island; 0.5 mile northwest of Oyster Lake; 200 feet southwest of canal; SW1/4NE1/4 sec. 30 T. 17 S., R. 6 E.

RANGE IN CHARACTERISTICS: Scatlake soils are continuously saturated with saline water. Soil salinity, or electrical conductivity, is 8 to more than 16 ds/m in more than half of the upper 50 cm. The n-value of all mineral horizons is 1 or more. Extractable sodium averages more than 20 percent in some horizons of the 10- to 40-inch particle-size control section. Most pedons have an organic surface layer 2 to 10 inches thick.

The Oa horizon, where present, has color with hue of 7.5YR or 10YR, value of 2 to 4, and chroma of 2 or less. Texture is muck or peat. Reaction ranges from slightly acid to moderately alkaline.

The A horizon has color with hue of 10YR to 5BG, or N, value of 2 to 5, and chroma of 2 or less. Texture is clay, mucky clay, or mucky silty clay loam. Reaction ranges from slightly acid to moderately alkaline.

The Cg horizons have color with hue of 10YR to 5BG, or N, value of 4 to 6, and chroma of 1 or less. Masses of iron accumulation range none to few in shades of brown. Texture is clay that is very fluid. Some pedons have thin layers of black muck. Reaction ranges from slightly acid to moderately alkaline.

COMPETING SERIES: These are the Bancker, Barbary, and Larose series in the same family. Similar soils are the Capers, Fausse, Gentilly, Harris, Ijam, and Placedo series. Bancker soils have n-value or 0.7 or more in the upper 20 inches. Barbary and Larose soils have less than 20 percent extractable sodium in the particle-size control section. In addition, Larose soils are continuously saturated with fresh water. Capers soils have 0.6 to 2.0 percent sulfides in the upper 20 inches of the solum. Fausse, Harris, Ijam, and Placedo soils have n-value less than 0.7 in all horizons. Gentilly soils have lower
horizons with n-value of less than 0.7.

GEOGRAPHIC SETTING: Gulf Coast Marsh, about 1 foot above sea level. These soils are formed in unconsolidated saline clayey and organic sediments that are too soft for cattle to graze. The climate is warm and humid. Mean annual precipitation is about 58 inches. Mean annual temperature is about 70 degrees F. near type location.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Harris, Ijam, and Placedo series and the Kenner series, which has organic layers more than 51 inches thick.

DRAINAGE AND PERMEABILITY: Very poorly drained; very slow runoff; very slowly permeable. Gulf storms and normal tides flood the area with salt water. The water level fluctuates between 1 foot above and 1/2 foot below the soil surface throughout the year. During tropical storms, tide floodwater is 4 feet deep or more.

USE AND VEGETATION: Wetland wildlife habitat. Vegetation is saltwater marsh plant species, such as marshhay cordgrass, big cordgrass, smooth cordgrass, seashore saltgrass, olney bulrush, saltmarsh bulrush, and needlegrass rush.

DISTRIBUTION AND EXTENT: In the saltwater marsh areas of Louisiana, Texas, and possibly Mississippi (MLRA 151). The series is of large extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas.

SERIES ESTABLISHED: Iberia Parish, Louisiana; 1973.

REMARKS: These soils were mapped Sharkey clay and Tidal Marsh on the 1911 soil survey of Iberia Parish. Mineral horizons turn black on air-drying. If drained, the classification changes.

Diagnostic horizons and features recognized in this pedon are:

Histic epipedon - 0 to 6 inches (Oa horizon)

n-value is 1 or more - 6 to 80 inches (A, Cg1, Cg2, Cg3, and Cg4 horizons)

Ecological Site: Saline Fluid Mineral Marsh.

ADDITIONAL DATA: Lousiana State University lab data (S94LA-109-005,011,013) from Terrebonne Parish.

TAXONOMIC VERSION: Soil Taxonomy, Second Edition,1999.


National Cooperative Soil Survey
U.S.A.