LOCATION IJAM TX+LAEstablished Series
TAXONOMIC CLASS: Fine, smectitic, nonacid, hyperthermic Vertic Fluvaquents
TYPICAL PEDON: Ijam clay--grass.
(Colors are for moist soil unless otherwise stated.)
A--0 to 8 inches; dark gray (10YR 4/1) clay; massive; very hard, very firm; many roots; strongly effervescent; moderately alkaline; diffuse smooth boundary. (2 to 10 inches thick)
Cg--8 to 80 inches; mixed dark gray (5Y 4/1) and gray (5Y 6/1) clay; massive; very hard, very firm; few fine roots mostly in the upper part; few thin discontinuous strata or lenses of sandy clay loam or fine sandy loam; common discontinuous bedding planes; few shells and shell fragments; few to common masses of iron accumulation in shades of yellowish brown and strong brown with clear and sharp boundaries in matrix; few to common iron depletions in shades of gray with diffuse and clear boundaries in matrix; moderately saline; moderately alkaline.
TYPE LOCATION: Chambers County, Texas; from Fort Anahuac Park in Anahuac, 0.2 mile west, 0.5 mile south and 50 feet west of road.
RANGE IN CHARACTERISTICS: These soils are saturated with water from three to six months during the year. Reaction ranges from neutral to strongly alkaline throughout. Some layers are calcareous but carbonates are not continuous in all parts between 10 and 20 inches. Electrical conductivity ranges from 4 to 16 dS/m throughout.
The A horizon has color with hue of 10YR to 5Y, value of 4 to 7, and chroma of 0 to 2. Texture of the A horizon is clay, clay loam, or loam.
The Cg horizon has color with hue of 10YR to 5Y, value of 4 to 7, and chroma of 0 to 2. Some pedons have color of bluish gray (5B 6/1). There are few to common masses of iron accumulation in shades of yellowish brown or strong brown. The texture of the 10 to 40 inch particle-size control section is clay, with the clay content ranging from 40 to 55 percent. Pockets, lenses or thin strata of sandy or loamy sediments occur at random throughout the pedon.
COMPETING SERIES: This includes the Barnett series in the same family. Similar soils are the Ambia, Angelina, Barbary, Capers, Gentilly, Harris, Neel, Sievers, and Sostien series. Barnett soils have n-value greater than 0.7 at a depth of 20 to 40 inches and deeper. Ambia soils are more acid and are saturated for shorter periods of time. Angelina soils have a fine-loamy particle-size control section and are strongly acid. Barbary and Gentilly soils have n-value greater than 0.7 throughout and have a very-fine particle-size control section. Capers soils have mixed mineralogy, are sulfurous, and have a n-value greater than 0.5. Harris soils have a mollic epipedon. Neel soils are moderately well drained. Sievers soils have a fine-loamy particle-size control section. Sostien soils are nonsaline.
GEOGRAPHIC SETTING: Ijam soils are on nearly level concave coastal areas bordering waterways, ditches, and canals. The soils developed in alkaline, saline, clayey sediments dredged or pumped from the floor of rivers, bays, and canals or from marshes in construction of canals or waterways. Slopes are dominantly less than 1 percent, but range from 0 to 2 percent. Mean average annual precipitation is 40 to 60 inches. Mean annual temperature is 70 to 72 degrees F. Frost-free days range from 250 to 280. Elevation ranges from 0 to 8 feet above sea level. Thornthwaite P-E index ranges 62 to 82.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Harris, Neel, and Sivers series, and the Surfside, Tracosa, and Velasco series. Surfside and Velasco soils have a mollic epipedon. Tracosa soils have n-value greater than 0.7. All of these soils are on lower natural landscapes. Neel and Sievers soils are on dredged materials in similar to higher landscape positions.
DRAINAGE AND PERMEABILITY: Poorly drained. Permeability is very slow. The water table ranges from the surface during wet periods to about 36 inches below the surface during dry periods. Runoff is very low. Ijam soils are frequently flooded with saline water during high tides. Flooding to a depth of severl feet occurs during major storms.
USE AND VEGETATION: Mainly used for rangeland. Vegetation is mostly waterloving, salt tolerant species such as gulf cordgrass and common reedgrass.
DISTRIBUTION AND EXTENT: Mainly along the upper Gulf Coast of Texas in the Gulf Marsh (MLRA 151). The series is of minor extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Chambers County, Texas; 1969.
REMARKS: Ijam soils were formerly unclassified and mapped as Made land.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 8 inches (A horizon)
Stratification from dredging operations.
Aquic conditions - saturation and reduction.
SOIL INTERPRETATION RECORD NUMBER: TX0058