LOCATION BEGAY                   UT+AZ CO

Established Series
Rev. WN/AJE
12/2022

BEGAY SERIES

The Begay series consists of very deep, well drained, moderately rapidly permeable soils that formed in eolian deposits and alluvium, derived mainly from sandstone. Begay soils are on structural benches, sand sheets on broad mesas, fan remnants, fan terraces and have slopes of 0 to 30 percent. The mean annual precipitation is about 12 inches, and the mean annual air temperature is about 48 degrees F.

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, nonsticky and nonplastic; common fine roots; few fine pores; slightly alkaline (pH 7.8); clear wavy boundary. (11 to 17 inches thick)

Bk--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, nonsticky and nonplastic; few fine roots; common fine pores; very slightly effervescent, carbonates occur in veins and are are disseminated; moderately alkaline (pH 7.9); gradual wavy boundary. (10 to 14 inches thick)

B--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, nonsticky and nonplastic; 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) moist; massive; soft, very friable, nonsticky and nonplastic; 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: Ustic aridic soil moisture regime
Mean annual soil temperature: 47 to 59 degrees F
Mean summer soil temperature at a depth of 20 inches: 61 to 65 degrees F.
Combined thickness of the A and B horizons: 35 to 50 inches
Depth to carbonates: 7 to 22 inches
Particle-size control: 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 7 dry, 3 to 6 moist
Chroma: 3 to 8, dry or moist
Reaction: slightly alkaline to moderately strongly alkaline
Calcium carbonate equivalent: 0 to 3 percent

Bw horizon
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 to 6 dry, 3 to 6 moist
Chroma: 3 to 8, dry or moist
Texture: very fine sandy loam, loamy very fine sand, fine sandy loam, loamy fine sand, loamy sand, sandy loam, loam
Reaction: slightly alkaline to strongly alkaline
Calcium carbonate equivalent: 0 to 5 percent

B, Bk and C horizons
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 to 8 dry, and 4 to 8 moist
Chroma: 3 to 8, 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 carbonate equivalent: 0 to 5 percent in the B and Bk; 1 to 10 percent in the C horizon

COMPETING SERIES: These are the Delvalle (NM), Ignacio (NM), Kitsili (I)(NM), Koshare (NM), Ojito (NM), Parida (NM), Ranchos (T)(NM), Remmit (CO)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 hue. Ranchos soils attempt to reflect the effects of soil forming agents unique to the Great Plains. Remmit soils have hue 10YR and yellower in the Bw, Bk, and C horizons.

GEOGRAPHIC SETTING: Begay soils occur on fan remanants, fan terraces, sand sheets on mesas, structural benches and broad mesa tops at elevations of 4,700 to 7,400 feet. Slopes range from 0 to 30 percent. These soils formed in very deep eolian and alluvial deposits derived from sedimentary rock formations. The mean annual precipitation ranges from 8 to 14 inches and the mean annual air temperature ranges from 44 to 57 degrees F. The frost-free period ranges from 110 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Thumbrock, Aneth and Sogzie soils. Thumbrock 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 for 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 SOIL SURVEY REGIONAL OFFICE (MO) 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 Begay concept does not include a calcic horizon

Soil classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, 11th Edition, 2010
Update and revision for the correlation of Navajo Mountain Area (AZ711) and Fort Defiance Area (AZ715), May 2008, CEM
Update and revision for the correlation of Arches National Park (UT687), February 2009, CEM
Restore parts of the original field description that affect the series concept. June 2009, WWJ
Updated and revised for the correlation of Canyonlands National Park (UT688), October 2009, WWJ
Update and revisions for the correlation of Chinle Area (AZ713), August 2011, LJG2

________________________________________

---

National Cooperative Soil Survey
U.S.A.