LOCATION HOCKLEY                 TX

Established Series
FFW-JKW-RM-AKS
08/2019

HOCKLEY SERIES

The Hockley series consists of very deep, well drained, moderately permeable soils that formed in loamy sediments derived from the Willis Formation. These nearly level to gently sloping soils occur on interfluves of the coastal plains. Slope ranges from 0 to 5, but are typically less than 3 percent. Mean annual temperature is about 20 degrees C (68 degrees F.), and mean annual precipitation is about 1143 mm (45 in).

TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, hyperthermic Plinthic Paleudalfs

TYPICAL PEDON: Hockley loamy fine sand - pasture. (Colors are for moist soil unless otherwise stated.)

A1--0 to 13 cm (0 to 5 in); very dark grayish brown (10YR 3/2) loamy fine sand, grayish brown (10YR 5/2) dry; weak fine granular structure; hard, very friable; many fine pores; many worm casts; neutral; gradual smooth boundary. (Thickness is 10 to 38 cm [4 to 15 in].)

A2--13 to 58 cm (5 to 23 in); dark grayish brown (10YR 4/2) fine sandy loam, grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; hard, very friable; common very fine and fine roots; few very fine tubular pores; 2 percent ironstone pebbles 10 to 15 mm in size; 1 percent fine distinct dark brown (7.5YR 3/4) iron concentrations with sharp boundaries lining pores; neutral; gradual smooth boundary. (Thickness is 13 to 64 [5 to 25 in].)

Bt--58 to 127 cm (23 to 50 in); yellowish brown (10YR 5/6) sandy clay loam; yellowish brown (10YR 5/6) dry; weak medium and coarse subangular blocky structure; very hard, friable; few distinct clay films on surfaces of peds and clay bridges between sand grains; 3 percent ironstone pebbles 10 to 15 mm in size; 5 percent fine and medium prominent red (2.5YR 4/6) iron concentrations with sharp boundaries in matrix; 3 percent medium distinct brown (7.5YR 4/3) iron-manganese concentrations with sharp boundaries lining pores; neutral; gradual wavy boundary. (Thickness is 25 to 102 cm [10 to 40 in].)

Btvc--127 to 191 cm (50 to 75 in); variegated matrix of 60 percent yellowish brown (10YR 5/6), 25 percent red (2.5YR 4/6), and 10 percent gray (10YR 6/1) sandy clay loam; weak and moderate medium subangular blocky structure; extremely hard, friable; common distinct yellowish brown (10YR 5/6) clay films on surfaces of peds and common prominent gray (10YR 5/1) clay films in gray (10YR 6/1) matrix; 2 percent of red (2.5YR 4/6) matrix is brittle; 10 percent medium red (2.5YR 4/8) plinthite; 10 percent ironstone pebbles 10 to 15 mm in size; slightly acid; diffuse wavy boundary. (Thickness is 38 to 89 [15 to 35 in].)

B't--191 to 254 cm (75 to 100 in); variegated matrix of 50 percent red (2.5YR 4/6), 40 percent yellowish brown (10YR 5/6), and 10 percent gray (10YR 6/1) sandy clay loam; medium subangular blocky structure; extremely hard, friable; common distinct yellowish brown (10YR 5/6) clay films on surfaces of2peds and common prominent gray (10YR 5/1) clay films in gray (10YR 6/1) matrix; 4 percent of red (2.5YR 4/6) matrix is brittle; 2 percent medium red (2.5YR 4/8) plinthite; 3 percent ironstone pebbles 10 to 15 mm in size, decreasing with depth; slightly acid.

TYPE LOCATION: Harris County, Texas; from intersections of Farm Road 149 and Farm Road 2920 in Tomball, 8.1 miles west on Farm Road 2920; 100 ft south of road in pasture. Hockley, Texas USGS Topographic quadrangle;Latitude 30 degrees, 04 minutes, 30 seconds North; Longitude 95 degrees, 45 minutes, 35 seconds West;Datum: WGS84

RANGE IN CHARACTERISTICS:
The solum is more than 203 cm (80 in) thick.

Soil Moisture: An udic soil moisture regime. The soil moisture control section, 10 to 30 cm (4 to 12 in), is typically moist from September to July in normal years. The cumulative total number of days the soil moisture control section is dry is less than 90 days.

Mean annual soil temperature: 21.7 to 22.2 degrees C (71 to 72 degrees F.
Depth to argillic horizon: 23 to 102 cm (9 to 40 in)
Depth to redox depletions: 122 to 140 cm (48 to 55 in)

Particle-size control section (weighted average)
Clay content: 25 to 30 percent
CEC/clay ratio: 0.25 to 0.40

Ap or A Horizon
Hue: 7.5YR or 10YR
Value: 3 to 5
Chroma: 2 to 4; Pedons with value of 3 and chroma of 2 or 3 are less than 25cm (10 in) thick.
Texture: fine sandy loam or loamy fine sand.
Redox concentrations: amount-0 to 2 percent, size-fine, contrast-faint, boundary-sharp, location-lining pores, shades-brown.
Reaction: moderately acid to neutral.

E Horizon (where present)
Hue: 7.5YR or 10YR
Value: 4 or 5
Chroma: 2 to 4
Texture: fine sandy loam or loamy fine sand.
Redox concentrations: amount-0 to 3 percent, size-fine, contrast-faint, boundary-sharp, location-lining pores, shades-brown.
Reaction: moderately acid to neutral.

Bt Horizon
Hue: 7.5YR or 10YR
Value: 5 to 7
Chroma: 4 to 6
Texture: loam, sandy clay loam, or clay loam.
Clay content: 20 to 30 percent
Clay films: location-surfaces of peds, contrast-faint or distinct.
Redox accumulations: amount 2 to 15 percent, size-fine or medium, contrast-faint to prominent, boundary-sharp, location-lining pores, in matrix, and on surfaces of peds, shades-red, yellow, or brown.
Ironstone nodules: 1 to 5 percent
Reaction: moderately acid to neutral.

Btvc Horizon
variegated matrix
Hue: 2.5YR (25 to 60 percent)
Value: 4
Chroma: 6 to 8
Hue: 7.5YR or 10YR (30 to 60 percent)
Value: 5 to 7
Chroma: 4 to 8
Hue: 10YR (10 to 40 percent)
Value: 5 to 7
Chroma: 1 or 2
Texture: sandy clay loam, clay loam, or sandy clay.
Clay content: 30 to 40 percent
Clay films: location-surfaces of peds, contrast-faint or distinct.
Ironstone nodules: 0 to 5 percent
Plinthite nodules: 0 to 5 percent
Reaction: moderately acid to neutral.

B't Horizon
variegated matrix
Hue: 2.5YR (30 to 60 percent)
Value: 4
Chroma: 6 to 8
Hue: 7.5YR or 10YR (30 to 60 percent)
Value: 5 to 7
Chroma: 4 to 8
Hue: 10YR (10 to 20 percent)
Value: 5 to 7
Chroma: 1 or 2
Texture: sandy clay loam, clay loam, or sandy clay.
Clay content: 20 to 40 percent
Clay films: location-surfaces of peds, contrast-faint or distinct.
Ironstone nodules: 1 to 15 percent
Plinthite nodules: 5 to 12 percent
Reaction: moderately acid to neutral.

COMPETING SERIES: There are no series in the same family. Similar soils are the Mockley (TX), Pinetucky (TX), Segno (TX), and Wockley (TX)series.
Mockley series: have base saturation less than 35 percent; fine particle-size control section
Pinetucky series: have base saturation less than 35 percent; thermic temperature regime
Segno series: thermic temperature regime
Wockley series: aquic conditions within 75 cm of the surface; somewhat poorly drained

GEOGRAPHIC SETTING: Parent material: Loamy sediments derived from the Willis Formation of late Pliocene to early Pleistocene age
Lanscape: coastal plain
Landform: interfluves
Slope: 0 to 5 percent, but are typically less than 3 percent
Mean annual temperature: 19.5 to 21.1 degrees C (67 to 70 degrees F.
Mean annual precipitation: 1041 to 1143 mm (41 to 49 in
Precipitation Pattern: Precipitation is fairly uniform throughout the year with slight peaks in the spring and fall. Summer moisture deficit ranges from 0 to 10 cm (0 to 4 in).
Frost-free period: 240 to 300 days
Elevation: 61 to 91 m (200 to 300 feet)
Thornthwaite annual P-E indices: 62 to 72

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gessner, Mockley, Snakecreek, and Wockley series.
Gessner soils: are ponded in depressions
Mockley soils: fine particle-size control section and on a similar to higher landscape position
Snakecreek soils: somewhat poorly drained and on a lower landscape position
Wockley soils: somewhat poorly drained and on a lower landscape position

DRAINAGE AND PERMEABILITY:
Drainage class: Well drained
Permeability: moderate permeability
Runoff: very low
A perched water table from about 102 to 152 cm (3.5 to 6 ft) exists during the winter months

USE AND VEGETATION: Used mainly as pastureland and cropland. Urban encroachment is common in the eastern portion of this series' extent. The dominant pasture grass is improved coastal bermudagrass. The dominant crop is corn. Native grasses are species of andropogons, paspalums, and panicums. Pine trees have encroached on many areas.

DISTRIBUTION AND EXTENT:
General area: Southeastern Texas, mainly east of the Colorado River along the interior margin of the Coastal Prairie
Land Resource Area: T (Atlantic and Gulf Coast Lowland Forest and Crop Region)
Major Land Resource Area: 150A (Gulf Coast Prairies)
Extent: moderate extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Harris County, Texas, 1922.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 58 to 108 cm (23 to 43 in). (Bt horizon)
Ochric epipedon: 0 to 58 cm (0 to 23 in). (A1 and A2 horizons)
Argillic horizon: 58 to 254 cm (23 to 100 in). (Bt, Btvc1, B't horizons)
More than 5 percent plinthite: 127 to 191 cm (50 to 75 in)in (Btvc)

Additional Comments: This series recognizes graded phases. The series description was updated during the soil data join and recorrelation initiative in 2014. MLRA 150 Soil Survey office sampled and redescribed the typical pedon during the update of MLRA 150A. The surface texture was changed from a fine sandy loam to a loamy fine sand.

The assignment of the cation-exchange activity class is supported by laboratory data number S00TX-473-1 from Waller County, Texas.

The mineralogy is supported by laboratory data on sample 72TX-101-3 (72L107).

ADDITIONAL DATA: Laboratory data from the Texas A&M University Soil Characterization Lab on sample S00TX-473-1 and the National Soil Survey Lab on sample 72TX-101-3 (72L107)

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

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National Cooperative Soil Survey
U.S.A.