LOCATION BEGAY UT+AZ COEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Ustic Haplocambids
TYPICAL PEDON: Begay loamy fine sand - rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; yellowish red (5YR 5/6) loamy fine sand, yellowish red (5YR 4/6) moist; single grained; loose; very slightly effervescent, carbonates are disseminated; moderately alkaline (pH 7.9); clear smooth boundary. (2 to 5 inches thick)
Bw--3 to 16 inches; yellowish red (5YR 5/6) very fine sandy loam, yellowish red (5YR 4/6) moist; weak medium subangular blocky structure; soft, friable; common fine roots; few fine pores; slightly alkaline (pH 7.8); clear wavy boundary. (11 to 17 inches thick)
Bk1--16 to 28 inches; yellowish red (5YR 5/6) very fine sandy loam, yellowish red (5YR 4/6) moist; weak medium subangular blocky structure; slightly hard, firm; few fine roots; common fine pores; very slightly effervescent, carbonates are disseminated; moderately alkaline (pH 7.9); gradual wavy boundary. (10 to 14 inches thick)
Bk2--28 to 42 inches; yellowish red (5YR 5/6) very fine sandy loam, yellowish red (5YR 4/6) moist; weak medium subangular blocky structure; slightly hard, firm; strongly effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (12 to 16 inches thick)
C--42 to 60 inches; yellowish red (5YR 5/8) very fine sandy loam, yellowish red (5YR 5/8) or yellowish red (5YR 4/6) moist; massive; soft, very friable; few fine pores; very slightly effervescent; carbonates are disseminated; moderately alkaline (pH 8.1).
TYPE LOCATION: San Juan County, Utah; 7 miles east and 5 miles north of Navajo Mountain School; SW 1/4, SE 1/4 sec. 31, T. 42 S., R. 17 E.
RANGE IN CHARACTERISTICS:
Soil moisture: In 7 out of 10 years the soils are dry in all parts of the moisture control section for 50 to 75 percent of the time (cumulative) that the soil temperature at depth of 20 inches is above 41 degrees F. The soils are moist in some part of the moisture control section for 30 to 40 days during the summer and are dry in some part of the moisture control section for 60 to 90 consecutive days during winter and early spring and are moist in some parts between July and October. Ustic aridic soil moisture regime.
Mean annual soil temperature: 47 to 57 degrees F
Mean summer soil temperature at a depth of 20 inches ranges from - 61 to 65
degrees F.
Combined thickness of A and B horizons is - 35 to 50 inches
Depth to secondary carbonates accumulation ranges from - 7 to 22 inches
Particle-size control section ranges from - 15 to 40 percent fine sand or coarser
Rock fragments: 0 to 15 percent
A horizon
Hue: 2.5YR, 5YR, 7.5YR, 10YR
Value: 4 to 6 dry, 3 to 6 moist
Chroma: 3 to 6, dry or moist
Reaction: slightly alkaline or moderately alkaline
Calcium carbonate equivalent: 0 to 3 percent
Bw horizon
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 4 to 8, dry or moist
Texture: very fine sandy loam, loamy very fine sand, fine sandy loam, loamy fine sand, sandy loam
Reaction: slightly alkaline to strongly alkaline
Calcium carbonate equivalent: 0 to 3 percent
Bk and C horizons
Hue: 2.5YR, 5YR, 7.5YR
Value: 5 to 8 dry, and 4 to 8 moist
Chroma: 4 to 6, dry or moist
Textures: very fine sandy loam, fine sandy loam, sandy loam, and thin strata of gravelly fine sandy loam, or loamy fine sand, below a depth of 40 inches
Reaction: slightly alkaline to strongly alkaline
Calcium carbonates equivalent: 0 to 5 percent
COMPETING SERIES: These are the Delvalle (NM), Ignacio (NM), Kitsili (NM), Koshare (NM), Ojito (NM), Parida (NM), Ranchos (NM), Sandspring (T AZ), and Turnback (WY) series. Delvalle soils have loamy sand and coarse sand substratums. Ignacio, Ojito, and Turnback are moderately deep to bedrock. Kitsili soils are inactive. Koshare soils contain 10 to 25 percent mica content in the coarse silt to fine sand fraction. Parida soils contain more than 15 percent rock fragments and have 10YR hues. Rancho soils attempt to reflect the effects of soil forming agents unique to the Great Plains. Sandspring soils have 10YR hues. Remmit and Sandspring soils have hue yellower than 7.5YR.
GEOGRAPHIC SETTING:
Parent Material: deep eolian deposits and alluvium from sedimentary rocks. Landform: fan remnants, structural benches, broad and mesa tops. Elevations are 4,700 to 7,400 feet. Slopes are 0 to 30 percent. The mean annual air temperature is 44 to 55 degrees F. The mean annual precipitation is 8 to 14 inches. The frost-free period is 110 to 175 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Anasazi, Aneth and Sogzie soils. Anasazi soils have calcic horizons and a lithic contact at 20 to 40 inches. Aneth soils do not have cambic horizons and have a sandy particle size control section. Sogzie soils have calcic horizons.
DRAINAGE AND PERMEABILITY: Well drained; very slow to medium runoff; moderately rapid permeability.
USE AND VEGETATION: Used only as livestock grazing. Vegetation is needleandthread, big sagebrush, blue grama, Indian ricegrass.
DISTRIBUTION AND EXTENT: Southeastern Utah, southwestern Colorado, and northern Arizona. Begay soils are moderately extensive. MLRA 35. This series should not be used outside of MLRA 35 and 36.
MLRA OFFICE RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: San Juan County, Utah, 1976
REMARKS:
Diagnostic horizons 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 16 inches (Bw horizon)
The Bk horizon is assumed to have too little carbonate to be a calcic horizon
Soil classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006.
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006.