LOCATION MOFFAT                  UT+NM

Established Series
Rev. RSJ/MJD/WWJ
10/2011

MOFFAT SERIES


The Moffat series consists of very deep, well drained, moderately rapidly permeable soils that formed in eolian and alluvial sediments. These soils are on plains, plains on structural benches, and alluvial fans and have slopes ranging from 1 to 25 percent. Mean annual air temperature is 51 degrees and average annual precipitation is 7 inches.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Typic Haplocalcids

TYPICAL PEDON: Moffat gravelly fine sand--on a 2 percent convex south-facing slope--rangeland. (Colors are for dry soil unless otherwise stated.)

A1--0 to 1 inch; yellowish red (5YR 5/6) gravelly fine sand, yellowish red (5YR 4/6) moist; single grain; soft, very friable; few very fine and fine roots; 20 percent fine and medium gravel on the soil surface; 15 percent gravel in the matrix; slightly calcareous, carbonates is disseminated; slightly alkaline (pH 7.8); abrupt smooth boundary. (1 to 12 inches thick)

A2--1 to 6 inches; yellowish red (5YR 5/6) loamy fine sand, yellowish red (5YR 4/6) moist; weak medium subangular blocky structure; soft, very friable; few very fine, fine and medium roots; few very fine pores; 5 percent gravel; moderately calcareous, carbonates are disseminated; slightly alkaline (pH 7.8); abrupt wavy boundary. (0 to 9 inches)

Bk1--6 to 13 inches; light reddish brown (5YR 6/4) fine sandy loam, yellowish red (5YR 5/6) moist; weak medium subangular blocky structure; slightly hard, friable; few very fine roots; few very fine pores; strongly calcareous, carbonates are disseminated; strongly alkaline (pH 8.6); clear wavy boundary. (5 to 18 inches thick)

Bk2--13 to 26 inches; pink (5YR 7/3) fine sandy loam, reddish yellow (5YR 6/6) moist; massive; hard, firm; few very fine roots; few very fine pores; strongly calcareous, carbonates are disseminated; strongly alkaline (pH 8.8); gradual wavy boundary. (13 to 22 inches thick)

C1--26 to 40 inches; reddish yellow (5YR 6/6) fine sandy loam, reddish yellow (5YR 6/6) moist; massive; hard, firm; few very fine roots; few very fine pores; moderately calcareous, carbonates are disseminated; strongly alkaline (pH 8.8); clear wavy boundary. (0 to 26 inches thick)

C2--40 to 60 inches; reddish yellow (5YR 6/6) fine sand, yellowish red (5YR 5/6) moist; massive; slightly hard, friable; moderately calcareous, carbonates are disseminated; strongly alkaline (pH 8.6).

TYPE LOCATION: Emery County, Utah; south of the Flat Tops; 840 feet north and 2,280 feet east of the southeast corner, sec. 34, T. 25 S., R. 13 E.

RANGE IN CHARACTERISTICS:

Mean annual soil temperature: 52 to 59 degrees F.

Soil moisture: Typic aridic moisture regime

Depth to calcic horizon: 3 to 20 inches

Clay content: 8 to 18 percent

A horizon
Hue: 2.5YR, 7.5YR, 5YR
Value: 4 to 7 dry, 3 or 5 moist
Chroma: 3 to 6, dry or moist
Rock fragments: 0 to 20 percent as desert pavement, and 0 to 15 percent gravel in the profile
Reaction: slightly alkaline to strongly alkaline

Bk horizon
Hue: 2.5YR, 7.5YR, 5YR
Value: 3 to 8 dry, 3 to 7 moist
Chroma: 2 to 8, dry or moist
Texture: fine sandy loam, very fine sandy loam, loam, sandy loam
Rock fragments: 0 to 35 percent gravel
Calcium carbonate: moderately calcareous or strongly calcareous
Calcium carbonate equivalent: 5 to 35 percent (Some pedons have thin subhorizons containing 35 to 60 percent calcium carbonate equivalent)
Reaction: moderately alkaline or strongly alkaline

C horizon
Texture: fine sand, loamy very fine sand, fine sandy loam, sand, loamy sand, loamy fine sand

COMPETING SERIES: These are Bluechief (UT), Boreham (UT), Hiko Springs (UT), Kaito (AZ), Kinan (AZ), McCutchen (NV), Nakai (UT), Nakoy (UT), Nolava (UT), Nuahs (NV), Pagina (AZ), Riemod (UT), Teabrush (UT), and Trook (WY) series. Kinan soils have stratifications at 20 to 40 inches. Bluechief soils have bedrock at depths of 30 to 40 inches. Kaito, Pagina, and Nakai soils have a paralithic contacts. Nakai and Nakoy soils have a calcic horizon with its upper boundary below 20 inches. Boreham, Nakoy, Nolava, Riemod, Teabrush, and Trook soils have soil temperature less than 52 degrees F. Boreham, Hiko Springs, McCutchen, Nolava, Riemod, and Trook soils have 7.5YR hue or yellower. McCutchen soils also have a lithologic discontinuity at depths below 40 inches. Nuahs soils have hue of 10YR. Hiko Springs, McCutchen, and Nuahs soils are in the Great Basin Desert (MLRAs 28A, 28B, 29) and have precipitation more evenly distributed throughout the year. Nakai, Nakoy and Teabrush soils have a cambic horizon.

GEOGRAPHIC SETTING: Moffat soils are on broad alluvial fan benches, plains on structural benches, and plains. Slopes range from 1 to 25 percent. The soils formed in eolian and alluvial sediments derived mainly from sandstone of the Entrada, Carmel and Navajo Formations. Elevation is 3,500 to 5,900 feet. The average annual precipitation is 5 to 10 inches. The mean annual temperature is 50 to 57 degrees F. The freeze-free period is 115 to 190 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Nakai soils and Sheppard soils. Sheppard soils have sandy particle-size control sections and lack a calcic horizon.

DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately rapid permeability.

USE AND VEGETATION: Moffat soils are typically used for live stock grazing. Potential vegetation is Indian ricegrass, galleta, spike dropseed, mesa dropseed, blackbrush, and Mormon-tea.

DISTRIBUTION AND EXTENT: Utah, Colorado, northeastern Arizona. MLRA 35. The series is of moderate extent.

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

SERIES ESTABLISHED: Uintah River Valley Area, Utah 1921.

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

Ochric epipedon - the zone from the surface to 6 inches (A1 and A2 horizons)

Calcic horizon - the zone from 6 to 26 inches (Bk1 and Bk2 horizons)

The range in soil temperature was added in March 1993 to differentiate Moffat from Chroder series. Moffat is a Typic aridic soil. Chroder is an ustic aridic soil. This soil was previously classified as a Typic Calciorthids.

Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Eleventh Edition, 2010

Updated competing series section March 2010. CEM

Update and revisions for the correlation of Little Colorado River Area (AZ707), Sept. 2011, CEM


National Cooperative Soil Survey
U.S.A.