LOCATION ADDICKS TXEstablished Series
TYPICAL PEDON: Addicks loam - pasture.
(Colors are for moist soil unless otherwise stated.)
Ap--0 to 11 inches; black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; weak fine subangular blocky structure; hard, friable; many fine roots; many fine pores; common worm casts; neutral; gradual wavy boundary. (10 to 18 inches thick)
Bt--11 to 23 inches; dark gray (10YR 4/1) loam, gray (10YR 5/1) dry; few fine faint mottles of strong brown; weak fine and medium subangular blocky structure; hard, friable; common fine roots; common fine pores; common worm casts of very dark gray (10YR 3/1) material; few FeMn concretions up to 5 mm. in diameter; few patchy clay films slightly darker than matrix; few very fine calcium carbonate concretions in lower part of horizon; neutral; gradual wavy boundary. (6 to 19 inches thick)
Btk1--23 to 49 inches; Light gray (10YR 7/1) loam, white (10YR 8/1) dry; 30 to 40 percent of matrix is light brownish gray (10YR 6/2); common fine faint pale yellow and few fine distinct yellow mottles; weak coarse subangular blocky parting to weak fine subangular blocky structure; very hard, friable; few fine roots; common fine pores; few patchy clay films; few black concretions; few worm casts; few crayfish krotovinas filled with dark gray (10YR 4/1) material; 20 percent by volume visible calcium carbonate in the form of soft masses and concretions less than 1 cm. in diameter; moderately alkaline; calcareous; clear wavy boundary. (15 to 30 inches thick)
Btk2--49 to 78 inches; light gray (10YR 7/2) loam, white (10YR 8/2) dry; many fine and medium distinct mottles of yellow (2.5Y 7/6); common medium and coarse distinct mottles of yellowish brown (10YR 5/8); weak very coarse prismatic parting to weak medium and coarse subangular blocky structure; very hard, firm; few clay films; few black concretions; few crayfish krotovinas filled with very dark gray (10YR 3/1) and dark gray (10YR 4/1) loamy material; prism faces coated with light brownish gray loam 2 to 15 mm. in thickness; 5 percent irregular shaped, pitted calcium carbonate concretions 1 to 6 cm. in diameter; moderately alkaline; noncalcareous.
TYPE LOCATION: Harris County, Texas; from Interstate Highway 10 in Addicks, 3.5 miles north on Texas Highway 6, 1.85 miles east on Clay Road, 75 feet south in pasture.
RANGE IN CHARACTERISTICS: The solum thickness is more than 72 inches. The mollic epipedon ranges from 10 to 20 inches thick. The soil matrix becomes calcareous at a depth of 16 to 29 inches.
The A horizon has hue of 10YR, value of 2 or 3, and chroma of 1 or 2. It is typically a loam, but ranges from very fine sandy loam to silt loam. The reaction ranges from slightly acid to moderately alkaline.
The Bt and Btk horizons have hue of 10YR or 2.5Y, value of 4 to 7, and chroma of 1 or 2, and contains few to common distinct brownish and yellowish mottles. Texture is loam or silt loam in the upper part, but ranges to silty clay loam in the lower part. The silicate clay content of the control section is 12 to 18 percent. The reaction ranges from neutral through moderately alkaline. The Btk horizon contains 15 to 40 percent calcium carbonate equivalent that occurs in the form of soft masses and few to common concretions with pitted surfaces.
COMPETING SERIES: There are no competing series in the same family. Similar soils are the Algoa, Bernard, Clodine, Jeanerette, Morey, and Stono series. Algoa soils are in a fine-loamy family and lack argillic horizons. Bernard soils contain more than 35 percent clay in the control section. Clodine soils lack mollic epipedons. Jeanerette and Morey soils have fine-silty control sections and have less than 15 percent calcium carbonate equivalent in the Bt horizon. Stono soils lack carbonates in the Bt horizon and have more than 18 percent clay in the control section.
GEOGRAPHIC SETTING: Addicks soils occur on level to slightly depressional areas of the Gulf Coast Prairies. Slopes are mainly less than 1 percent. The soil formed in thick unconsolidated loamy sediments of Pleistocene age. The mean annual temperature ranges from about 68 to 70 degrees F.; the mean annual precipitation from 40 to 52 inches and Thornthwaite annual P-E indices range from 62 to 82.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bernard and Clodine soils of the competing series and the Aris, Gessner, and Midland soils. Aris soils have fine textured control sections and Gessner soils have Ochric epipedons fine-loamy control sections and lack calcic horizons. Midland soils have fine textured control sections and lack a Mollic epipedon.
DRAINAGE AND PERMEABILITY: Poorly drained; slow surface runoff and internal drainage; moderate permeability. Water table is at 12 to 30 inches below the surface for 1 to 2 months during most years.
USE AND VEGETATION: Used mainly for pasture and growing rice. Native grasses are species of Andropogons, Paspalums, and Panicums. A few pine and hardwood trees have encroached on some areas.
DISTRIBUTION AND EXTENT: Gulf Coast Prairies of southeast Texas. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Harris County, Texas; 1973.
REMARKS: These soils were formerly included in the Clodine and Morey series.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 11 inches.
Argillic horizon - 11 to 78 inches.
Calcic horizon - 23 to 49 inches.
Aquic moisture regime.