LOCATION ALGOA                   TX

Established Series
ELG-GWC-KBH-AKS
07/2019

ALGOA SERIES

The Algoa series consists of deep, moderately well drained, moderately slowly permeable soils formed in thick, loamy sediments. These nearly level soils are pimple mounds on coastal prairies of Pleistocene age. Slope ranges from 0 to 3 percent. Mean annual precipitation is about 1397 mm (55 in) and the mean annual air temperature is about 21 degrees C (69 degrees F).

TAXONOMIC CLASS: Fine-loamy, siliceous, superactive, hyperthermic Typic Argiudolls

TYPICAL PEDON: Algoa silt loam--pasture (Colors are for moist soil unless otherwise stated.)

A--0 to 31 cm (0 to 12 in); very dark gray (10YR 3/1) silt loam, dark gray (10YR 4/1) dry; weak fine subangular blocky structure; hard, friable, nonsticky and nonplastic; common fine roots; common fine pores; few worm-casts; slightly alkaline; clear smooth boundary. (Thickness is 18 to 41 cm [7 to 15 in])

Btk1--31 to 46 cm (12 to 18 in); grayish brown (10YR 5/2) loam, light brownish gray (10YR 6/2) dry; weak coarsesubangular blocky structure; hard, friable, nonsticky and nonplastic; few fine roots; 15 percent soft masses of calcium carbonate; common fine pitted concretions of calcium carbonate; 20 percent calcium carbonate equivalent; moderately alkaline; calcareous; clear smooth boundary.

Btk2--46 to 109 cm (18 to 43 in); light brownish gray (10YR 6/2) loam, light gray (10YR 7/2) dry; weak coarse subangular blocky structure; hard, friable; slightly sticky and slightly plastic; few fine roots; 30 percent soft masses of calcium carbonate; common fine pitted concretions of calcium carbonate; 33 percent calcium carbonate equivalent; few medium black concretions; moderately alkaline; calcareous gradual smooth boundary. (Combined thickness is 10 to 89 cm [4 to 35 in])

Btk3--109 to 147 cm (43 to 58 in); light gray (10YR 7/2) loam, very pale brown (10YR 8/2) dry; common fine distinct yellowish brown (10YR 5/8) mottles; weak coarse subangular blocky structure; hard, friable, sticky and slightly plastic; few fine roots; 35 percent soft masses of calcium carbonate; common fine pitted concretions of calcium carbonate; 45 percent calcium carbonate equivalent; moderately alkaline; calcareous; gradual smooth boundary.

2C--147 to 165 cm (58 to 65 in); gray (10YR 6/1) clay loam, light gray (10YR 7/1) dry; many fine prominent yellowish brown (10YR 5/6) mottles; massive; very hard, very firm, sticky and plastic; few medium pitted concretions of calcium carbonate; few medium black concretions; moderately alkaline.

TYPE LOCATION:
Galveston County, Texas; from intersection of Farm Road 3002 and Farm Road 1266, near Dickinson, 0.3 mile north on Farm Road 1266, 200 feet east on a shell road and 50 feet north in a pasture.

USGS topographic quad: Dickinson; TX
Latitude: 29 degrees, 29 minutes, 50.82 seconds N
Longitude: 95 degrees, 2 minutes, 46.43 seconds W
Datum: WGS84

RANGE IN CHARACTERISTICS:
Soil Moisture: A Udic soil moisture regime. The soil moisture control section is moist in some or all parts for more than 275 days in normal years.

Mean annual soil temperature: 21.7 to 22.8 degrees C (71 to 73 degrees F)

Particle-size control section (weighted average)
Clay content: 18 to 35 percent

A horizon
Hue: 10YR or 2.5Y
Value: 2 or 3
Chroma: 1 or 2
Texture: silt loam, loam, fine sandy loam, or silty clay loam
Reaction (pH): slightly acid through moderately alkaline (pH 6.1 to 8.4)

E horizon (where present)
Hue: 10YR or 2.5Y
Value: 2 to 4
Chroma: 2 to 4
Texture: very fine sandy loam, fine sandy loam, or loam
Reaction (pH): slightly acid through moderately alkaline (pH 6.1 to 8.4)

Upper Bt horizon
Hue: 10YR or 2.5Y
Value: 3 through 7
Chroma: 2
Texture: silt loam, loam, clay loam, or silty clay loam
Iron accumulations: amount- 1 to 20 percent, color- shades of brown or yellow
Reaction (pH): moderately alkaline and calcareous but, in some pedons, it is a thin horizon that is neutral to slightly alkaline and noncalcareous. (pH 7.0 to 8.4)

Lower Btk horizons
Hue: 10YR or 2.5Y
Value: 5 to 8
Chroma: 1 to 3
Texture: loam, clay loam, or silty clay loam
Iron accumulations: amount- 1 to 20 percent, color- shades of yellow and brown
Reaction (pH): neutral to moderately alkaline and calcareous (pH 7.0 to 8.4)

2C horizon (where present)
Hue: 10YR or 2.5Y
Value: 4 to 7
Chroma: 1 to 6
Texture: clay loam, sandy clay loam, or clay
Iron accumulations: amount- 0 to 30 percent, color- shades of yellow and brown
Reaction (pH): neutral through moderately alkaline and noncalcareous (pH 7.0 to 8.4)

COMPETING SERIES:
There are no competing series in the same family. Series in similar families include Addicks, Clodine, Jeanerette, Mocarey, and Morey series.
Addicks soils: have less than 18 percent clay in the particle size control section
Clodine, Jeanerette, and Morey soils: occur on different geomorphic positions

GEOGRAPHIC SETTING:
Parent material: loamy fluviomarine deposits derived from igneous, metatmorphic and sedimentary rock
Landscape: coastal plains
Landform: pimple mounds
Slope: 0 to 3 percent
Mean annual precipitation: 1219 to 1473 mm (48 to 58 in)
Thornwaite annual P-E indices: 62 to 80
Mean annual air temperature range: 20 to 22.2 degrees C (68 to 72 degrees F)
Frost-free period: 330 to 340 days
Elevation: 3 to 31 m (10 to 100 ft)

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the competing Mocarey and Morey soils and the Aris, Bernard, Crowley, Leton soils. Mocarey soils: adjacent to Algoa soils on flat landforms
Aris, Crowley, and Morey soils occur on similar landscapes in areas that lack free carbonates
Bernard soils: occur on slightly lower positions
Leton soils: occur in depressional areas

DRAINAGE AND PERMEABILITY:
Drainage class: Moderately well drained
Permeability class: moderately slow
Runoff: low
The soil has a perched water table at about 2 feet during the winter and that is about 5 feet during the dry part of the summer. Some areas are subject to brief flooding during high intensity rains because runoff is not removed rapidly enough.

USE AND VEGETATION:
Used mainly for pasture and range. A few areas are used for field crops and truck crops. The native vegetation is largely a mixture of Andropogon and Paspalum species with some sedges.
Ecological sites assigned to phases and components of this series are listed below. Current ecological site assignments are in Web Soil Survey. Components of this series include the following ecological sites: Northern Loamy Prairie

DISTRIBUTION AND EXTENT:
General area: Gulf Coast Prairies of Southeast Texas
Land Resource Region: T (Atlantic and Gulf Coast Lowland Forest and Crop Region)
Major Land Resource Area: 150A (Gulf Coast Prairies)
Extent: not extensive.

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

SERIES ESTABLISHED: Galveston County, Texas, 1981.

REMARKS: The soil was formerly included in the Addicks, Clodine, and Morey series.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - 0 to 31 cm (0 to 12 in) (A horizon)
Argillic horizon - 31 to 147 cm (12 to 58 in) (Btk horizons)
Calcic horizon - 31 to 147 cm (12 to 58 in) (Btk horizons)

ADDITIONAL DATA: Classification was changed to include an argillic horizon based on field descriptions and laboratory data.
NSSL Sample No. S81TX-167-3 suggests some evidence of moved clay in the lower solum. This is interpreted as a buried argillic horizon and the series is classified by the easily identified calcic horizon.

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

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National Cooperative Soil Survey
U.S.A.