LOCATION MURDOCK UTEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Petrocalcidic Palexerolls
TYPICAL PEDON: Silt loam - idle cropland (Colors are for dry soils unless otherwise noted.)
Ap--0 to 4 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; weak thick platy structure that parts to moderate fine granules; slightly hard, very friable, slightly sticky, slightly plastic; few fine roots; noncalcareous; slightly alkaline (pH 7.5); clear smooth boundary. (4 to 6 inches thick)
A--4 to 9 inches; brown (10YR 4/3) silt loam, dark brown (10YR 3/3) moist; weak thick platy structure that parts to weak fine subangular blocks; slightly hard, friable, slightly sticky, slightly plastic; few fine roots and pores; noncalcareous; neutral (pH 7.2); clear wavy boundary. (4 to 6 inches thick)
Ck1--9 to 15 inches; brown (10YR 5/3) silty loam, brown (10YR 4/3) moist; very weak subangular blocky structure; hard, friable, sticky, plastic; few fine roots and pores; strongly calcareous; secondary lime occurs as threads and splotches; slightly alkaline (pH 7.8); gradual irregular boundary. (5 to 8 inches thick)
Ck2--15 to 27 inches; very pale brown (10YR 7/3) silt loam, brown (10YR 5/3) moist; weak coarse subangular blocky structure; hard, firm, slightly sticky, slightly plastic; strongly calcareous; massive lime accumulation; moderately alkaline (pH 8.1); clear wavy boundary. (7 to 16 inches thick)
Ckm--27 inches; indurated lime hardpan.
TYPE LOCATION: Beaver County, Utah; 3.5 miles north of the Beaver post office on U.S. Highway 91, 2.8 miles east and 1.4 miles northeast; SW1/4 of sec. 25, T.28S., R.7W.; lat. 38 degrees 20 minutes 23.73 seconds N. and long. 112 degrees 35 minutes 52.34 seconds W., NAD 83.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 50 degrees F., and the mean summer soil temperature at a depth of 20 inches is 63 to 69 degrees F. These soils are dry in the moisture control section more than 50 percent of the time the soil temperature is above 41 degrees F and are continually dry for 50 to 70 consecutive days during the summer months in more than 6 out of 10 years.
The depth to the indurated hardpan ranges from 20 to 36 inches. Depth to the Ck horizon ranges from 8 to 12 inches. The control section ranges from loam to silt loam containing l0 to 18 percent clay and more than 15 percent sand coarser than very fine sand. It is slightly or moderately alkaline.
The A horizon has value of 4 or 5 dry and chroma of 2 of 3. lt ranges from thick platy and moderate fine granular structure to weak and moderate fine subangular blocky structure. This horizon is neutral or slightly alkaline. A few fine lime hardpan fragments are present in some pedons.
The Ck horizon has hue of 7.5YR or 10YR value of 5 through 7 dry, 4 or 5 moist, and chroma of 2 or 3.
The Ckm horizon is indurated but may be fractured to a very limited extent in some pedons.
COMPETING SERIES: This is the Pavant series. Pavant soils have more than 18 percent clay in the control section and are less than 20 inches deep over an indurated hardpan.
GEOGRAPHIC SETTING: Murdock soils are on dissected terraces at elevations of 6,000 to 6,500 feet. Slopes are generally less than 6 percent, but range to 40 percent. The soils formed in alluvial soil material from intermediate and basic igneous parent rocks. The climate is semiarid. Mean annual temperature is 45 to 48 degrees F., mean summer temperature is 64 to 70 degrees F. Mean annual precipitation is 12 to 14 inches distributed fairly uniformly throughout the year except June is drier; 77 percent falls when the average monthly temperature is above 32 degrees F. The average frost-free period is 104 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Flowell and Ushar soils. Flowell soils have argillic horizons with more than 35 percent clay and lack petrocalcic horizons. Ushar soils lack petrocalcic horizons and average more than 18 percent clay in the control section.
DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; moderate permeability above the hardpan and very slow or no permeability in the hardpan.
USE AND VEGETATION: Used mainly for irrigated cropland and rangeland. Vegetation is pasture, small grains, alfalfa or rangeland plants including juniper, pinyon, big sagebrush, Indian ricegrass, squirreltail, and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Southwestern Utah. This series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Beaver County, Utah, 1972.
REMARKS: 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.