LOCATION PALOPINTO TXEstablished Series
The Palopinto series consists of well drained, moderately permeable, shallow and very shallow soils over limestone bedrock that formed in residuum from from Pennsylvanian limestone bedrock. These soils are on ridges and plains. Slopes are dominantly about 2 percent, but range from 1 to 20 percent.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Lithic Haplustolls
TYPICAL PEDON: Palopinto stony clay loam, on a 2 percent slope, in rangeland. (Colors are for dry soil unless otherwise stated.)
A1--0 to 4 inches; dark grayish brown (10YR 4/2) stony clay loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky and moderate fine granular structure; hard, friable; many fine roots; many fine pores; few wormcasts; about 30 percent fragments of limestone from 6 to 30 inches across, and 5 percent less than 3 inches across; moderately alkaline; clear smooth boundary. (2 to 12 inches thick)
A2--4 to 12 inches; dark grayish brown (10YR 4/2) extremely stony clay loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky and moderate fine granular structure; hard, friable; common fine roots; common fine pores; few wormcasts; about 70 percent of fragments of limestone that are from 6 to 30 inches across; moderately alkaline; abrupt wavy boundary. (4 to 16 inches thick)
R--12 to 14 inches; indurated limestone; coarsely fractured; contains less than 5 percent fine-earth in fractures and crevices.
TYPE LOCATION: Palo Pinto County, Texas; from the intersection of U.S. Highway 180 and U. S. Highway 281 in Mineral Wells, Texas; 8 miles north on U. S. Highway 281; 3.6 miles west and north on Texas Highway 254 and 1600 feet east of highway in rangeland.
RANGE IN CHARACTERISTICS: Solum thickness and depth to hard bedrock ranges from 6 to 20 inches. The solum contains 35 to 85 percent coarse fragments of limestone, the amount ranging from 15 to 60 percent in the A1 horizon and from 50 to 90 percent in the A2 horizon. Coarse fragments are nonflat subangular to flat limestone, ranging in size from 0.5 inch to 36 inches across the long axis, dominantly 6 to 20 inches. Reaction ranges from neutral to moderately alkaline. The soil is typically noncalcareous but some pedons are weakly effervescent with hydrochloric acid. Mean annual soil temperature ranges from 64 to 69 degrees F.
The A horizon has hue of 5YR, 7.5YR or 10YR, value of 3 or 4, chroma of 2 or 3. The fine earth fraction is clay loam, silty clay loam, loam, or silt loam with 18 to 35 percent total clay content with stony, cobbly, or flaggy modifiers.
COMPETING SERIES: These include the
Brewster (TX),
Budlamp (AZ),
Canquya (AZ),
Eckert (TX),
Kiti (OK),
Rayford (OK),
Siphoncan (AZ),
Timhill (OK), and
Yarbam (AZ) series. Similar soils include the
Aledo,
Catto,
Eckrant,
Tarrant, and
Woodford series. Brewster soils are dry in the moisture control section for slightly longer periods. In addition, Brewster soils developed in material weathered from basalt. Budlamp soils contain less than 18 percent clay in the control section. Canquya soils receive significant amounts of winter precipitation and have mean annual soil temperatures less than 64 degrees F. Eckert soils are formed from limestone containing appreciable glauconite. Kiti and Rayford soils are moist in the soil moisture control section for longer periods. Siphoncan soils developed in noncalcareous parent material. Timhill soils have sola 10 to 20 inches thick over rhyolite. Yarbam soils contain less than 18 percent clay in the control section.
Aledo soils have carbonatic mineralogy. Catto soils developed in material weathered from chert. Eckrant and Tarrant soils contain more than 35 percent clay in the control section. Woodford soils are less clayey, moist in the soil moisture control section for longer periods, and have siliceous mineralogy.
GEOGRAPHIC SETTING: Palopinto soils are along gently sloping ridges and moderately steep hillsides. Slopes range from 1 to 20 percent. These soils formed in hard crystalline limestone of the Strawn and Canyon groups of Pennsylvanian age. Mean annual precipitation ranges from 24 to 30 inches and mean annual temperature ranges from 62 to 67 degrees F. Frost free days range from 210 to 240 days, and elevation ranges from 1,000 to 2,000 feet. Thornthwaite P-E indices range from 36 to 48.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Tarrant series, which are on similar landscapes, and the Hensley, Leeray, Lindy, Owens, and Set series. Hensley soils have red argillic horizons and are on stream divides usually above Palopinto soils. Leeray soils are clayey throughout and are below on stream divides or in valleys. Lindy soils have sola 20 to 40 inches thick and are below on stream divides. Owens soils are shallow clayey soils above hillsides. Set soils have sola more than 40 inches thick and are below on knolls or intermingled with Palopinto soils.
DRAINAGE AND PERMEABILITY: Well drained. Permeability of the soil is moderate above a very slowly permeable bedrock. Runoff is medium on 1 to 3 percent slopes, high on 3 to 5 percent, and very high on slopes greater than 5 percent.
USE AND VEGETATION: Used for rangeland. Native vegetation includes sideoats grama, little bluestem, and annual grasses. There are scattered liveoak, juniper, tasajillo, and pricklypear. Whitebrush and sumac are usually present. Forbs include bushsunflower, western ragweed, and gayfeather.
DISTRIBUTION AND EXTENT: North-central Texas, mainly in the Texas North-central Prairie land resource area. The series is extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Palo Pinto County, Texas; 1979.
REMARKS: This soil has formerly been included in the Tarrant series. Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 12 inches. (A1 and A2 horizons).
Lithic contact - hard limestone at a depth of 12 inches ( top of R layer).
ADDITIONAL DATA: NSSL sample 384TX-429-1.