LOCATION ASHDOWN            UT+WY
Established Series
Rev. TAD/RLM/MJD
03/2003

ASHDOWN SERIES


The Ashdown series consists of very deep, well drained, moderately slowly permeable soils that formed in alluvium from sandstone, siltstone, shale, and limestone. Ashdown soils are on alluvial fans and alluvial plains. Slopes are 0 to 8 percent. The average annual precipitation is about 10 inches and the mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, mesic Xeric Torriorthents

TYPICAL PEDON: Ashdown loam--cropland. (Colors are for air-dry soil unless otherwise noted.)

Ap1--0 to 5 inches; light brown (7.5YR 6/4) loam, brown (7.5YR 4/3) moist; weak thin platy structure; slightly hard, friable, slightly sticky and plastic; common fine and few medium roots; common fine pores; strongly calcareous; carbonates are disseminated; moderately alkaline (pH 8.4); clear smooth boundary. (2 to 5 inches thick)

Ap2--5 to 9 inches; light brown (7.5YR 6/4) loam, brown (7.5YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and plastic; common fine and very fine and few medium roots; common fine and very fine and few medium pores; strongly calcareous; carbonates are disseminated; moderately alkaline (pH 8.4); clear wavy boundary. (3 to 7 inches thick)

C1--9 to 24 inches; light reddish brown (5YR 6/4) loam, reddish brown (5YR 4/4) moist; weak medium subangular blocky structure; hard, friable, sticky and plastic; few very fine, fine and medium roots; common fine and few medium pores; strongly calcareous; carbonates are disseminated; strongly alkaline (pH 8.5); clear wavy boundary. (6 to 18 inches thick)

C2--24 to 33 inches; reddish brown (5YR 5/4) loam, yellowish red (5YR 4/6) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine, fine and medium roots; common fine and very fine pores; moderately calcareous; carbonates are disseminated; strongly alkaline (pH 8.6); gradual smooth boundary. (7 to 26 inches thick)

C3--33 to 45 inches; yellowish red (5YR 5/6) loam, yellowish red (5YR 4/6) moist; massive; hard, friable, slightly sticky and plastic; few fine roots; common very fine and few medium pores; moderately calcareous; carbonates are disseminated; strongly alkaline (pH 8.6); gradual smooth boundary. (7 to 30 inches thick)

C4--45 to 65 inches; light reddish brown (5YR 6/4) loam, reddish brown (5YR 4/4) moist; massive; hard, friable, slightly sticky and plastic; few fine roots; many very fine, common fine and few medium pores; moderately calcareous; carbonates disseminated; strongly alkaline (pH 8.6); clear smooth boundary.

TYPE LOCATION: Iron County, Utah; located about 800 feet south and 300 feet east of the projected NW corner of section 2, T. 36 S., R. 11 W.

RANGE IN CHARACTERISTICS: The mean annual soil temperature at depths of 20 inches ranges from 50 to 53 degrees F. The mean summer soil temperature ranges from 67 to 71 degrees F. The moisture control section is continually dry in all parts for 60 to 75 days during the summer, and is continually moist in all parts for 60 to 75 days during the winter and early spring. The moisture regime is aridic bordering on xeric.

The 10 to 40 inch series particle-size control section averages 18 to 27 percent clay and more than 15 percent fine sand or coarser. Coarse-fragment content ranges from 0 to 35 percent.

The Ap and C horizons have hue of 7.5YR, 5YR or 2.5YR, value of 4 or 6 dry, 3 through 5 moist, and chroma of 2 through 6. It is loam, silt loam, fine sandy loam, clay loam, sandy loam, silty clay loam, or sandy clay loam. It is mildly alkaline to strongly alkaline. Some pedons have less than 3 percent gypsum in the C horizon. Electrical conductivity ranges from 0 to 16 mmhos/cm in the lower part of the C horizon.

COMPETING SERIES: These are the Bandag (T UT) and Braffits (UT) series. The Bandag soils have hue of 7.5YR or 10YR in the C horizon. The Braffits soils average 27 to 35 percent clay in the particle size control section.

GEOGRAPHIC SETTING: Ashdown soils occur on alluvial fans and alluvial flats at elevations of 4,800 to 6,500 feet. Slopes range from 0 to 8 percent. These soils formed in alluvium from sandstone, siltstone, shale, limestone, conglomerate and igneous rock. The mean annual temperature is 45 to 52 degrees F. The mean summer temperature is 68 to 72 degrees F. Average annual precipitation is 9 to 12 inches. The freeze-free period is 100 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Calcross, Modena, Wales, Woodrow and Naplene soils. Calcross and Modena soils have a coarse-loamy particle-size control section. Naplene and Woodrow soils have a fine-silty particle-size control section. Wales soils occur in flood plains and have an irregular decrease in organic matter.

DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; slow to moderate permeability.

USE AND VEGETATION: Used mainly for cropland. Alfalfa and small grains are the main irrigated crops. The potential vegetation is big sagebrush, squirreltail, yellowbrush, western wheatgrass, and tall native bluegrass.

DISTRIBUTION AND EXTENT: Southern Utah. These soils are moderately extensive. MLRA 28A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Fairfield-Nephi Area, Utah, 1981.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - the zone from 0 to 9 inches. (Ap1 and Ap2 horizons).

The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.


National Cooperative Soil Survey
U.S.A.