LOCATION HAMMOND TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, nonacid, thermic Udic Ustorthents
TYPICAL PEDON: Hammond fine sandy loam--revegetated pasture. (Colors are for moist soil unless otherwise stated).
A--0 to 8 inches; dark brown (10YR 3/3) fine sandy loam, brown (10YR 5/3) dry; weak medium subangular blocky structure parting to weak fine granular; hard, friable, sticky and plastic; common fine and medium roots; few medium aggregates with loam and clay loam texture; neutral; abrupt wavy boundary. (5 to 9 inches thick)
C1--8 to 13 inches; dark gray (10YR 4/1) clay loam, gray (10YR 5/1) dry; common fine and medium distinct brown (10YR 5/4), brownish yellow (10YR 6/8), and few fine faint gray (10YR 6/1) iron accumulations and aggregates of native soil and geologic material with loam and clay loam texture; massive, mixed with weak fine and medium subangular blocky structure; very hard, firm, sticky and plastic; common fine roots; few fine lignite fragments; few fine mica flakes; few medium very dark gray (10YR 3/1) shale fragments; slightly alkaline; clear wavy boundary.
C2--13 to 36 inches; light olive brown (2.5Y 5/3) clay loam, light yellowish brown (2.5Y 6/3) dry; common fine distinct brownish yellow (10YR 6/8), few fine and medium distinct light gray (2.5Y 7/1), and few fine distinct dark grayish brown (10YR 4/2) masses and aggregates of native soil and geologic material; massive, mixed with weak fine and medium subangular blocky structure; hard, friable, sticky and plastic; few fine roots; few fine lignite fragments; few fine and medium ironstone fragments; few fine mica flakes; few fine and medium grayish brown (10YR 5/2) shale fragments; slightly alkaline; diffuse wavy boundary.
C3--36 to 48 inches; light olive brown (2.5Y 5/3) clay loam, light yellowish brown (2.5Y 6/3) dry; few fine and medium distinct light gray (2.5Y 7/1) and yellowish brown
(10YR 5/8) masses and aggregates of native soil and geologic material; massive, mixed with weak fine and medium subangular blocky structure; hard, firm, sticky and plastic; few fine roots; few fine strata of clay; common fine lignite fragments; few fine ironstone concretions; few fine and medium grayish brown (2.5Y 5/2) and very dark gray (10YR 3/1) shale fragments; slightly alkaline; gradual wavy boundary.
C4--48 to 60 inches; light brownish gray (2.5Y 6/2) clay loam, light gray (2.5Y 7/2) dry; common fine and medium distinct yellowish brown (10YR 5/6) and dark grayish brown (10YR 4/2) masses and aggregates of native soil and geologic material; massive, mixed with weak coarse platy structure parting to weak fine and medium subangular blocky; hard, firm, sticky and plastic; few fine roots; few fine and medium aggregates of loam and clay loam texture; common fine lignite fragments; common fine and medium dark gray (10YR 4/1), grayish brown (10YR 5/2), and yellowish brown (10YR 5/4) shale fragments; slightly alkaline; gradual wavy boundary.
C5--60 to 80 inches; light olive brown (2.5Y 5/3) clay loam, light yellowish brown (2.5Y 6/3) dry; common fine distinct brownish yellow (10YR 6/8) and grayish brown (10YR 5/2) masses of native soil and geologic material; massive, mixed with weak fine and medium subangular blocky structure; hard, friable, sticky and plastic; few fine roots; few fine lignite fragments; few fine and medium grayish brown (10YR 5/2) shale fragments; slightly alkaline. (Combined thickness of C horizons is 60 to more than 80 inches)
TYPE LOCATION: Robertson County, Texas: from the intersection of Texas Highway 14 and Farm Road 46 in Bremond; 1.7 miles west on Highway 14, 3.6 miles south on County Road 426; then 1,000 feet west in pasture. (Latitude: 31 degrees, 05 minutes, 58 seconds; Longitude: 96 degrees, 39 minutes, 42 seconds).
RANGE IN CHARACTERISTICS: The combined thickness of the A and C horizons is greater than 80 inches. The surface layer is composed mainly of the topsoil material that was removed from the native soils and stockpiled. Blocky masses and aggregates in the C horizon are relict native soil and geologic materials. Fragments of diagnostic soil material averages less than 3 percent between 10 and 40 inches. Lignite fragments, ironstone fragments, and mica flakes range from few to about 3 percent by volume in most pedons. Weighted average clay content of the 10- to 40- inch particle-size control section ranges from 20 to 35 percent. Textures are mixed and variable within short distances.
The A horizon has hue of 10YR, value of 3 to 5, and chroma of 1 to 3. Masses and aggregates of soil material and clayey shale in shades of brown or yellow range from few to common. Texture is fine sandy loam, loam, sandy clay loam, or clay loam. Clay content ranges from 15 to 25 percent. Reaction ranges from slightly acid to slightly alkaline.
The C horizon has hue of 10YR or 2.5Y, value of 4 to 8, and chroma of 1 to 6. Lignite and ironstone fragments range from 0 to about 10 percent. Relict masses, aggregates, or mottles from the native soil in shades of red, yellow, brown, or gray range from none to common. Texture is mainly clay loam but some pedons are loam. Some pedons contain discontinuous layers, streaks, or masses of loamy sand, fine sandy loam, silty clay, or clay. Reaction is neutral or slightly alkaline.
COMPETING SERIES: This is the Gibbonscreek series. Similar soils are the Barge (OK), Bigbrown, Distell (T), Diswood (T), Grayrock, Kanima (OK), Marklake, Pirkey, and Thermo (T) series. Gibbonscreek soils do not have mollic colors in the surface horizon in the majority of pedons. Barge, Distell, Diswood, Kanima, Marklake, Pirkey and Thermo soils have greater than 3 percent fragments of diagnostic horizons between 10 and 40 inches, and have a udic moisture regime (Udarents). In addition, Barge soils are in the fine-silty family, Diswood and Thermo soils are in the fine family, and Kanima soils are in the loamy-skeletal family. Bigbrown soils are in the fine-silty family.
GEOGRAPHIC SETTING: Hammond soils are on areas reclaimed following surface lignite mining operations. They are forming in loamy reclaimed materials. They are on gently sloping to moderately steep slopes with slope gradients ranging from 1 to 15 percent. Mean annual precipitation ranges from 32 to 40 inches, and mean annual temperature ranges from 65 to 70 degrees F. Frost free days range from 240 to 280, and elevation ranges from 300 to 500 feet. The Thornthwaite P-E indices range from 44 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chazos, Crockett, Edge, Gasil, Lufkin, Padina, Rader, Sandow, Silawa, Tabor, Uhland, and Wilson soils. The Crockett, Edge, Gasil, Padina, and Tabor soils are on uplands of the Wilcox formation. The Chazos, Lufkin, Rader, Silawa, and Wilson soils are on high terraces. Sandow and Uhland soils are on bottomlands.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is slow. Runoff is medium on 1 to 5 percent slopes, and high on 5 to 15 percent slopes.
USE AND VEGETATION: Most areas are in pasture of coastal bermudagrass. Some areas are planted to mid and tall native grasses. Small grains and legumes are used to prevent erosion on areas that have been recently reclaimed.
DISTRIBUTION AND EXTENT: East Central Texas (MLRA 87A). The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES PROPOSED: Robertson County, Texas; 1995.
REMARKS: These soils are mainly reclaimed overburden materials from the Wilcox geologic group.
Superactive cation exchange activity class based on an average of 43 samples taken on Walnut Creek Mining Company lands.
Diagnostic horizons and features recognized with this pedon are:
Ochric epipedon - 0 to 8 inches (A horizon)
Soil Interpretation Record: TX1317