LOCATION SANTO TXEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, active, calcareous, thermic Typic Ustifluvents
TYPICAL PEDON: Santo fine sandy loam, on an undulating 1 percent slope, in pasture.
(Colors are for dry soil unless otherwise stated.)
A1--0 to 8 inches; light yellowish brown (10YR 6/4) fine
sandy loam, yellowish brown (10YR 5/4) moist; weak fine subangular blocky structure; slightly hard, very friable; many fine roots;
many fine pores; calcareous; moderately alkaline; abrupt smooth boundary. (4 to 15 inches thick)
C1--8 to 12 inches; brown (10YR 4/3) loam, dark brown (10YR
3/3) moist; massive; slightly hard, very friable; many fine roots; many fine pores; calcareous; moderately alkaline; abrupt smooth boundary. (4 to 12 inches thick)
C2--12 to 36 inches; pale brown (10YR 6/3) fine sandy loam, brown (10YR 5/3) moist; massive; slightly hard, very friable;
common fine roots, many fine pores; prominent bedding planes; calcareous; moderately alkaline; abrupt smooth boundary. (15 to
30 inches thick)
C3--36 to 44 inches; very pale brown (10YR 7/4) loamy fine
sand, yellowish brown (10YR 5/4) moist; massive; loose; few fine roots; prominent bedding planes; calcareous; moderately alkaline; abrupt smooth boundary. (6 to 20 inches thick)
C4--44 to 70 inches; light yellowish brown (10YR 6/4) fine
sandy loam, yellowish brown (10YR 5/4) moist; massive; slightly
hard, very friable; common thin strata of loamy fine sand; calcareous; moderately alkaline; abrupt smooth boundary. (20 to
40 inches thick)
C5--70 to 80 inches; brown (10YR 4/3) fine sandy loam; dark brown (10YR 3/3) moist; massive; slightly hard, very friable; thin strata of loamy fine sand; calcareous; moderately alkaline.
TYPE LOCATION: Palo Pinto County, Texas; from the junction of
Farm Road 4 and Farm Road 129 at Santo, 3.9 miles east on Farm
Road 129; 0.7 mile south on private road through pasture. Site is
in bermudagrass pasture 100 feet east on channel of Palo Pinto
Creek.
RANGE IN CHARACTERISTICS: The 10 to 40 inch control section is stratified fine sandy loam, loamy fine sand, or loam with thin
strata of sandy clay loam or silt loam. Clay content of the 10 to
40 inch control section is 5 to 18 percent and more than 15
percent is coarser than very fine sand. Reaction is moderately alkaline and calcareous, however, mildly alkaline strata are
common.
The A horizon has hue of 7.5YR or 10YR, value of 5 through 7, and chroma of 3 through 6. It is fine sandy loam, loam, or loamy fine sand.
The C horizons are in hue of 10YR, value of 4 through 8, chroma of
3 or 4.
COMPETING SERIES: These include the
Yahola series in the same
family and the
Bosque,
Bunyan,
Camargo,
Clairemont,
Colorado,
Energy,
Lincoln,
Pulaski,
Pulexas,
Rio Grande,
Yomont,
Zalla, and
Zavala series in similar famlies. Bosque, Bunyan, Colorado, and Energy soils have 18 to 35 percent clay in the 10 to 40 inch
control section. Camargo and Clairemont soils have fine-silty control sections. Lincoln and Zalla soils are loamy fine sand or coarser. Pulaski, Pulexas, and Zavala soils are noncalcareous. Yahola soils have stratified layers with hues redder than 7.5YR. Yomont soils have coarse-silty control sections.
GEOGRAPHIC SETTING: Santo soils are on nearly level to gently undulating flood plains of streams. Flooding occurs once every 1
to 10 years. Slopes are mainly 0 to 1 percent, but range from 0
to 2 percent. The soil formed in stratified calcareous alluvium. Mean annual temperature ranges from 62 degrees to 70 degrees F.;
mean annual precipitation from 25 to 40 inches; and Thornthwaite annual P-E indices from 40 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Bosque
and
Energy series and the
Frio series. Frio soils have a mollic epipedon and fine control section. These soils are in larger
flood plains generally slightly below Santo soils.
DRAINAGE AND PERMEABILITY: Santo soils are well drained. Runoff
is slow, and the permeability is moderately rapid.
USE AND VEGETATION: Mostly used for bermudagrass pastures and
pecan orchards. Some areas are farmed to forage sorghums and
small grains. Native vegetation consists of big bluestem, indiangrass, little bluestem, switchgrass and Texas needlegrass
with an overstory of pecan and elm trees. Forbs include western ragweed, engelmanndaisy, bush sunflower, dalea, and baldwin
ironweed.
DISTRIBUTION AND EXTENT: Mainly along small and medium size
streams in central and north-central Texas. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Palo Pinto County, Texas; 1979.
REMARKS: Santo soils were formerly classified in the Alluvial
great soil group. These soils were formerly included with the
Yahola soils.