LOCATION MOAB UT+AZEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, mesic Ustic Haplocalcids
TYPICAL PEDON: Moab gravelly fine sandy loam--rangeland. (Colors are for air-dry soil unless otherwise stated.)
A--0 to 3 inches; brown (7.5YR 5/4) gravelly fine sandy loam, brown (7.5YR 4/4) moist; weak fine granular structure; soft, loose; many very fine, common fine, few medium and coarse roots; 15 percent pebbles; moderately calcareous; carbonates are disseminated; moderately alkaline (pH 8.4); abrupt smooth boundary. (1 to 3 inches thick)
Bw--3 to 10 inches; brown (7.5YR 5/4) gravelly fine sandy loam, strong brown (7.5YR 4/6) moist; moderate medium subangular blocky structure; soft, very friable; common very fine and fine, few medium and coarse roots; common fine and few medium pores; 20 percent pebbles and 5 percent cobbles; moderately calcareous; carbonates are disseminated and thin pendants on the underside of rock fragments; strongly alkaline (pH 9.0); gradual wavy boundary. (4 to 8 inches thick)
Bk1--10 to 29 inches; pinkish white (7.5YR 8/2) very gravelly fine sandy loam, pinkish gray (7.5YR 7/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine pores; 50 percent pebbles and 10 percent cobbles; very strongly calcareous; carbonates are in common soft masses and thick pendants on the underside of rock fragments; strongly alkaline (pH 8.8); clear wavy boundary. (10 to 30 inches thick)
Bk2--29 to 60 inches; pink (7.5YR 7/4) very gravelly fine sandy loam, light brown (7.5YR 6/4) moist; single grained; soft, loose, slightly sticky; few very fine roots; 40 percent pebbles and 15 percent cobbles; very strongly calcareous; carbonates in few soft masses and thin coatings on the underside of rock fragments; strongly alkaline (pH 8.6).
TYPE LOCATION: Grand County, Utah, about 5 miles east of Cisco, 1,400 feet north and 500 feet east of the southwest corner of sec. 24, T. 21 S., R. 24 E.
RANGE IN CHARACTERISTICS:
Soil moisture: dry 65 to 75 percent of the time when the soil temperature at 20 inches is higher than 41 degrees F. These soils are usually dry during May and June and are moist in some part for short periods, usually less than 45 consecutive days during July through October. Ustic aridic moisture regime.
Mean annual soil temperature: 54 to 57 degrees F.
Depth to calcic horizon: 4 to 20 inches.
Particle-size control section -
Rock fragment: averages 35 to 65 percent
Clay content: 11 to 18 percent
Calcium carbonates equivalent: 40 to 60 percent.
A horizon
Hue: 5YR or 7.5YR.
Chroma: 4 to 6 dry.
Reaction: slightly alkaline or moderately alkaline and slightly calcareous or moderately calcareous.
Bw horizon
Value: 4 to 5 moist
Chroma: 4 to 6 dry and moist.
Texture: fine sandy loam, gravelly fine sandy loam, cobbly fine sandy loam and very cobbly fine sandy loam.
Reaction: moderately alkaline or strongly alkaline.
Bk horizon
Value: 6 to 8 dry, 4 to 7 moist
Chroma: 2 to 4 dry and moist.
Texture: very gravelly fine sandy loam and very cobbly fine sandy loam.
Reaction: moderately alkaline or strongly alkaline.
COMPETING SERIES: These are the
Ildecarb (NM),
Ladron (NM),
Puice (NM),
Socorro (NM),
Stormitt (UT),
Storsun (WY), and
Tusayan (AZ) series. Ildecarb soils average 18 to 35 percent clay in the particle size control section.
Ladron soils have lithologic discontinuities at 26 to 36 inches and average 18 to 26 percent clay in the particle size control section.
Puice, Socorro and Tusayan have bedrock at depths of 20 to 40 inches. Stormitt soils contain more than 18 percent clay in the particle size control section.
Storsun soils contain 18 to 25 percent clay in the particle size control section.
GEOGRAPHIC SETTING: Moab soils are on alluvial fans, alluvial terraces and alluvial valley floors and formed in alluvium from intermediate igneous and sedimentary rocks. Elevations range from 4,600 to 5,400 feet. Mean annual temperature is 52 to 54 degrees F. and average annual precipitation is 8 to 10 inches. Precipitation during the growing season occurs in March and early April and again July through October. Late April, May and June are usually very dry. The freeze-free period is about 140 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barnum, Mido, Rizno, Sheppard, Thoroughfare, and Strych soils. The Barnum soils have more than 18 percent clay and less than 35 percent rock fragments in the particle size control sections. Mido and Sheppard soils have sandy particle size control sections. Rizno soils have bedrock within 20 inches of the surface. Thoroughfare soils have less than 35 percent rock fragments in the particle size control section. Strych soils have mixed mineralogy.
DRAINAGE AND PERMEABILITY: Well drained, medium runoff; moderately rapid permeability.
USE AND VEGETATION: Used mainly for rangeland and wildlife habitat. Some areas are used for irrigated cropland and homesites. The potential vegetation is blackbrush, galleta, and Indian ricegrass.
DISTRIBUTION AND EXTENT: Southeastern Utah. The series is of small extent. MLRA 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Canyonlands Soil Survey Area -Parts of Grand and San Juan Counties, Utah, 1980. Named after the city of Moab.
REMARKS: Diagnostic horizon and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 3 inches (A horizon)
Cambic horizon - the zone from 3 to 10 inches (Bw horizon)
Calcic horizon - the zone from 10 to 60 inches (Bk1 and Bk2 horizons)
Classified according to Soil Taxonomy Second Edition, 1999.