LOCATION MOTA UTEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Typic Haplocalcids
TYPICAL PEDON: Loamy very fine sand - rangeland (Colors are for dry soil unless otherwise noted.)
A--0 to 6 inches; yellowish red (5YR 5/6) loamy very fine sand, strong brown (7.5YR 5/6) moist; single grained; loose, soft; few medium and fine roots; many fine interstitial pores; moderately calcareous; strongly alkaline (pH 8.6); clear wavy boundary. (4 to 10 inches thick)
Bk--6 to 23 inches; pinkish gray (7.5YR 7/2) very fine sandy loam, light brown (7.5YR 6/4) moist; moderate medium granular structure; hard, firm, sticky, slightly plastic; few fine roots; few very fine pores; very strongly calcareous; very strongly alkaline (pH 9.2); clear irregular boundary.
C--23 to 48 inches; reddish yellow (5YR 6/6) loamy very fine sand, yellowish red (5YR 5/6) moist; massive; loose, soft; very fine roots; common fine and very fine pores; moderately calcareous; strongly alkaline (pH 8.6).
TYPE LOCATION: San Juan County, Utah; about 4 1/2 miles northwest of Red Mesa pumping station; 600 feet north and 600 feet west of the SE corner of sec. 11, T.43S., R.22E., S.L.B.&M.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 54 to 58 degrees F.
Soil moisture: Mota soils are dry 65 to 75 percent of the time. Typic aridic moisture regime.
Depth to calcic horizon: 6 and 15 inches (They are calcareous in all parts above the calcic horizon)
Texture: very fine sandy loam
Clay content: 12 to 15 percent
A horizon
Value: 6 or 7 dry, 4 through 6 moist
Chroma: 4 through 6
Bk horizon
Hue: 5YR or 7.5YR
Value: 5 through 8 dry, 4 through 6 moist
Chroma: 2 through 4
C horizon
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 through 6.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Mota soils are on undulating to rolling uplands and benches at elevations of 4,800 to 5,400 feet. Slopes are 1 to 8 percent. The climate is semiarid. These soils were formed in deep eolian very fine sand deposits. The mean annual temperature is about 54 degrees F. and the mean summer temperature is about 77 degrees F. The average annual precipitation is 6 to 8 inches. Frost-free period is about 150 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aneth and Sheppard soils. Aneth soils have textures that average loamy fine sand in the control section and lack a calcic horizon. Sheppard soils have loamy fine sand and coarser textures throughout the control section and lack a calcic horizon.
DRAINAGE AND PERMEABILITY: Well-drained; slow to medium runoff; moderate to moderately rapid permeability.
USE AND VEGETATION: Used only as rangeland. Vegetation is blackbrush, Indian ricegrass, galleta grass, Russian thistle, and Mormon tea.
DISTRIBUTION AND EXTENT: Southeastern Utah and probably northern Arizona. This series is moderately extensive. MLRA 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: San Juan County Utah, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to a depth of about 6 inches. (A horizon)
Calcic horizon - The zone from 6 to about 23 inches. (Bk horizon)
Classified according to Soil Taxonomy Second Edition, 1999.
The Mota soils were formerly classified as Calcisols.