LOCATION ASA TX+OK

Established Series
Rev. CLN-GLL-KBH
02/2018

ASA SERIES

The Asa series consists of very deep, well drained, soils formed in loamy alluvium. These nearly level to very gently sloping soils are on flood plains. Slopes range from 0 to 3 percent. Mean annual precipitation is about 1143 mm (45 in) and the mean annual air temperature is about 20.6 degrees C (69 degrees F).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, hyperthermic Fluventic Hapludolls

TYPICAL PEDON: Asa silty clay loam--cropland. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 15 cm (0 to 6 in); black (5YR 2.5/1) silty clay loam, dark reddish gray (5YR 4/2) dry; moderate fine and medium subangular blocky structure; hard, firm; many very fine and fine roots, few medium roots; few fine pores; few worm casts, neutral; clear smooth boundary. (10 to 20 cm [4 to 8 in] thick)

A--15 to 36 cm (6 to 14 in); black (10YR 2/1) silty clay loam, very dark gray (10YR 3/1) dry; moderate coarse prismatic structure parting to moderate medium subangular blocky; hard, firm; few very fine and fine roots; few fine pores; about 5 percent vertically oriented worm holes about 1/8 inch across filled with brown worm casts; neutral; clear smooth boundary. (15 to 30 cm [6 to 12 in] thick)

B/A--36 to 48 cm (14 to 19 in); brown (7.5YR 4/4) silty clay loam, pink (7.5YR 7/4) dry, dark brown (7.5YR 3/2) (40 percent A); weak coarse prismatic structure parting to moderate medium subangular blocky; hard, firm; few fine roots; common very fine and fine pores; about 5 percent vertically oriented worm holes about 0.6 cm (1/4 in) across filled with black or brown worm casts; common very fine mica flakes; strongly effervescent; moderately alkaline; clear smooth boundary. (0 to 25 cm [0 to 10 in] thick)

Bw1--48 to 69 cm (19 to 27 in); brown (7.5YR 4/4) silty clay loam, pink (7.5YR 7/4) dry; about 15 percent by volume dark brown (7.5YR 3/2) A material; weak coarse prismatic structure parting to moderate medium and fine subangular blocky; hard, friable; few fine roots; common fine and medium pores; about 2 percent fine pitted calcium carbonate nodules; about 5 percent vertically oriented worm holes about 0.6 cm (1/4 in) across filled with black worm casts; few very fine mica flakes; violently effervescent; moderately alkaline; clear smooth boundary.

Bw2--69 to 84 cm (27 to 33 in); brown (7.5YR 4/4) silty clay loam; pink (7.5YR 7/4) dry; weak coarse prismatic structure parting to moderate medium and fine subangular blocky; hard, friable; few fine roots; many very fine and fine pores; about 2 percent fine pitted calcium carbonate nodules; about 5 percent dark brown material on faces of prisms; about 5 percent vertically oriented worm holes about 0.6 cm (1/4 in) across filled with black worm casts; few very fine mica flakes; violently effervescent; moderately alkaline; clear smooth boundary. (Combined thickness of the Bw horizon is 25 to 152 cm [10 to 60 in])

Bk--84 to 97 cm (33 to 38 in); brown (7.5YR 4/4) silty clay loam, pink (7.5YR 7/4) dry; weak coarse prismatic structure parting to moderate medium subangular blocky; hard, friable; few fine roots; few very fine and fine pores; few fine prominent reddish brown (2.5YR 4/4) and few fine distinct yellowish red (5YR 4/6) redox concentrations; about 5 percent medium pitted calcium carbonate nodules; few films, threads and masses of calcium carbonate; about 5 percent worm holes about 1.2 cm (1/2 in) across filled with black worm casts; violently effervescent; moderately alkaline; abrupt smooth boundary. (0 to 51 cm [0 to 20 in] thick)

B'w1--97 to 124 cm (38 to 49 in); brown (7.5YR 4/4) and reddish brown (5YR 4/3) silt loam, pink (7.5YR 7/4) dry; moderate coarse prismatic structure parting to weak fine angular blocky; hard, friable; few fine roots; many fine and medium pores; common fine and medium faint brown (7.5YR 5/4) redox concentrations; 2 percent medium and coarse pitted calcium carbonate nodules; few brown very thin coatings on faces of prisms; about 5 percent worm holes 1.2 cm (1/2 in) across filled with very dark gray worm casts; common very fine mica flakes; few fine snail shells fragments; violently effervescent; moderately alkaline; abrupt smooth boundary.

B'w2--124 to 155 cm (49 to 61 in); reddish brown (5YR 4/4) silt loam, reddish yellow (7.5 6/6) dry; moderate coarse prismatic structure parting to weak fine subangular blocky; hard, friable; few fine roots; many very fine and few fine and medium pores; few coarse pitted calcium carbonate nodules; few brown and red very thin coatings on faces of prisms; about 5 percent vertically oriented worm holes 0.6 cm (1/4 in) across filled with black worm casts; few very fine mica flakes; violently effervescent; moderately alkaline; clear smooth boundary.

B'w3--155 to 180 cm (61 to 71 in); brown (7.5YR 5/4) silt loam, brown (7.5YR 4/4) dry; weak coarse prismatic structure parting to weak fine angular blocky; hard, friable; few fine roots; many fine pores; few fine faint strong brown (7.5YR 5/6) redox concentrations; about 2 percent medium pitted calcium carbonate nodules; common fine and medium brown coatings along root channels; about 3 percent vertically oriented worm holes 0.6 cm (1/4 in) across filled with black worm casts; few very fine mica flakes; violently effervescent; moderately alkaline; clear smooth boundary.

B'w4--180 to 203 cm (71 to 80 in); reddish brown (5YR 4/4) silty clay loam, light brown (7.5YR 6/4) dry; weak coarse prismatic structure parting to weak fine angular blocky; hard, firm; few fine roots; common fine pores; few fine faint reddish brown (5YR 5/4) redox concentrations; few coarse pitted calcium carbonate nodules; about 3 percent vertically oriented worm holes about 0.6 cm (1/4 in) across filled with black worm casts; violently effervescent; moderately alkaline; abrupt smooth boundary. (Combined thickness of the B'w horizon is 0 to 152 cm [0 to 60 in])

TYPE LOCATION: Wharton County, Texas; from the intersection of U.S. Highway 59 and Texas Highway 60 north of Wharton, 0.8 mile south on Texas Highway 60, 0.25 mile west on County Road 222, and 195 ft south in cropland. Wharton USGS quad; Latitude: 29 degrees, 21 minutes, 23 seconds N; Longitude: 96 degrees,, 05 minutes, 45 seconds W. UTM Easting 781953 m, UTM Northing 3250976 meters, UTM Zone 14.NAD 83

RANGE IN CHARACTERISTICS:
Soil Moisture: An udic moisture regime. These soils remain moist in some part of the moisture control section more than 275 days in normal years.
Solum thickness is more than 203 cm (80 in). The A and upper B horizons of most pedons contain 20 to 40 percent worm casts.
Particle-size control section
Clay content: 18 to 35 percent
Silt Content: more than 40 percent
Sand Content: less than 15 percent fine sand and coarser sand.
Organic-carbon content decreases irregularly between a depth of 25 to 127 cm (10 and 50 in). Also, organic-carbon content ranges from 0.3 to 0.5 at a depth of 127 cm (50 in)
Some pedons near the coast range from slightly to strongly saline because of saltwater intrusion during storms.

A horizon:
Hue: 5YR to 10YR
Value: 2 or 3
Chroma: 1 to 3
Texture: silt loam or silty clay loam
Effervescence: none
Reaction: neutral to moderately alkaline.

B/A horizon (where present):
Hue: 5YR to 10YR
Value: 2 or 3
Chroma: 1 to 3
Texture: silt loam or silty clay loam
Effervescence: none or slight
Reaction: slightly alkaline or moderately alkaline

Bw and B'w horizons:
Hue: 5YR to 10YR
Value: 4 to 6
Chroma: 3 to 8
Texture: very fine sandy loam, loam, silt loam, or silty clay loam
Effervescence: slight to violent
Reaction: moderately alkaline

Bk horizon:
Hue: 5YR to 10YR
Value: 4 to 6
Chroma: 3 to 8
Texture: very fine sandy loam, silt loam, or silty clay loam.
Secondary calcium carbonate: amount-5 to 10 percent; kind-films, threads, masses or pitted nodules
Effervescence: slight to violent
Reaction: moderately alkaline

Some pedons have a buried A horizon at a depth of 152 to 203 cm (60 to 80 in).

COMPETING SERIES: There are no other series in the same family. Similar soils are the Clemville, Norwood, and Weswood series.
Clemville, Norwood, and Weswood soils: ochric epipedon; Weswood soils are in the ustic moisture regime.

GEOGRAPHIC SETTING:
Parent material: loamy alluvium derived from mixed sources from the Permian redbed sediments
Landscape: River valleys on flat coastal plain
Landform: Flood plains
Slope: 0 to 3, dominantly less than 1 percent
Mean annual soil temperature: 21.5 to 22 degrees C (70.5 to 72 degrees F)
Mean annual air temperature: 20 to 22.0 degrees C (68 degrees to 72 degrees F)
Mean annual precipitation: 1092 to 1245 mm (43 to 49 in)
Frost-free period: 270 to 300 days
Elevation: 0.9 to 46 m (3 to 150 ft)
Thornthwaite P-E Index: 56 to 70

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clemville , Norwood, Brazoria, and Pledger series.
Clemville and Norwood soils: have an ochric epipedon and are on a similar landform.
Brazoria and Pledger soils: are clayey throughout and are on a slightly lower positions on the a similarl landformn.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is negligible on slopes of less than 1 percent and very low on slopes of 1 to 3 percent. Flooding ranges from rare to frequent except where protected by manmade levees.

USE AND VEGETATION: Used mainly for cropland. The major crops are cotton, corn, sorghums, and truck crops. Native vegetation is Virginia wildrye, big bluestem, indiangrass, little bluestem, switchgrass, eastern gammagrass, sedges, low panicum, and perennial forbs. Trees are mainly pecan, elm, and hackberry.

DISTRIBUTION AND EXTENT: On flood plains of the lower Brazos and Colorado Rivers in the Coast Prairie area of Texas; LRR T, MLRA 150A (Gulf Coast Prairies). This series is of moderate extent.

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

SERIES ESTABLISHED: McLennan County, Texas; 1941.

REMARKS: The classification of the series was changed from thermic Fluventic Haplustolls to hyperthermic Fluventic Hapludolls 1/93 based on geographic distribution of the series.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon: 0 to 36 cm (0 to 14 in) (Ap and A horizons).

Cambic horizon: 36 to 203 cm (14 to 80 in) (B horizons).

Fluventic feature: irregular decrease of organic carbon between 25 and 127 cm (10 and 50 in). B'w1 and B'w2 horizons contain 0.5 and 0.3 organic carbon respectively.

ADDITIONAL DATA: TAMU characterization data from type location in Wharton County, TX (S92TX-481-001). SDHPT data from Washington County, TX (S73TX-239-004) and Brazoria County, TX (S76TX-039-019).

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014.

National Cooperative Soil Survey
U.S.A.