LOCATION DETRA                   UT+CO

Established Series
Rev. RSJ/JPP/TWH
01/2023

DETRA SERIES

The Detra series consists of deep, well drained soils that formed in slope alluvium, or eolian deposits, over residuum derived from sedimentary rocks. Detra soils are on hills, hillslopes, toeslopes, mesas, and mountain slopes. Slopes range from 0 to 40 percent. Mean annual precipitation is about 18 inches and the mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Pachic Argiustolls

TYPICAL PEDON: Detra fine sandy loam on rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 3 inches; dark brown (7.5YR 3/2) fine sandy loam; very dark brown (10YR 2/2) moist; moderate medium granular structure; soft, friable, slightly sticky and slightly plastic; many fine and common medium roots; many fine vesicular pores; slightly alkaline (pH 7.6); clear smooth boundary. (2 to 11 inches thick)

A2--3 to 8 inches; dark brown (7.5YR 3/2) fine sandy loam; very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and common medium roots; many fine vesicular pores; slightly alkaline (pH 7.6); clear smooth boundary. (0 to 19 inches thick)

BA--8 to 14 inches; dark brown (7.5YR 3/2) sandy clay loam, very dark brown (7.5YR 2/2) moist; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common fine and few medium roots; common fine and few medium pores; slightly alkaline (pH 7.8); clear smooth boundary. (0 to 13 inches thick)

Bt1--14 to 27 inches; brown (7.5YR 4/2) sandy clay loam, dark brown (7.5YR 3/2) moist; moderate coarse prismatic structure; very hard, firm, moderately sticky and moderately plastic; common fine roots; common fine and few medium pores; common distinct clay films on faces of peds; slightly alkaline (pH 7.8); clear wavy boundary. (6 to 38 inches thick)

Bt2--27 to 44 inches; yellowish red (5YR 4/6) clay loam, yellowish red (5YR 4/6) moist; strong coarse prismatic structure parting to moderate medium subangular blocky; extremely hard, extremely firm, very sticky and moderately plastic; common fine roots; few fine pores; common faint clay films and slickensides on faces of peds; moderately alkaline (pH 8.0); abrupt irregular boundary. (0 to 28 inches thick)

R--44 inches; limestone bedrock with clay loam as described above extending into the cracks.

TYPE LOCATION: Washington County, Utah; just south of the deer exclosure on Cable Mountain Road in Zion National Park; about; located about 1,200 feet south and 800 feet east of the northwest corner of sec. 13, T. 41 S., R. 10 W.

RANGE IN CHARACTERISTICS:
Soil moisture regime: The soils are moist for greater than 55 percent of the time during the period the soil temperature is above 41 degrees F. They are moist in some parts of the soil moisture control section for 35 to 50 days during the summer months, and are dry for 60 to 75 days during the 120 days following the winter solstice. The moisture regime is Typic Ustic.
Mean annual soil temperature: 40 to 47 degrees F
Mean annual summer soil temperature: 62 to 65 degrees F
Depth to lithic contact: 40 to 60 inches
Thickness of the mollic epipedon: 16 to 44 inches

Particle-size control section:
Clay content: 18 to 35 percent
Rock fragment content: 0 to 15 percent

A horizon:
Hue: 5YR to 10YR
Value: 2 to 5 dry, 2 or 3 moist
Chroma: 1 to 3 dry or moist
Texture: fine sandy loam, sandy clay loam, silty clay loam, or loam
Rock fragment content: 0 to 15 percent
Reaction: neutral to moderately alkaline

Bt horizon:
Hue: 5YR to 7.5YR
Value: 4 to 6 dry, 2 to 5 moist
Chroma: 2 to 6 dry or moist
Texture: sandy clay loam, clay loam, or loam
Rock fragment content: 0 to 15 percent
Reaction: neutral to moderately alkaline

Some pedons have BC, 2BC, or Bk horizons:
Hue: 5YR to 10YR
Value: 5 to 7 dry, 4 to 5 moist
Chroma: 3 or 4 dry or moist
Texture fine earth fraction: sandy clay loam, fine sandy loam, or sandy loam
Rock fragment content: 0 to 60 percent
Calcium carbonate equivalent: less than 15 percent

COMPETING SERIES: Current competitors are the Bowbells, Brycan, Carfall, Center Creek, Chugcreek, Fiesta, Flaxton, Hereford, Hesperus, Laceycreek, Ohwiler, Pachel, Peta, Schauson, Todacheene, Trag, and Weed series.
The Hereford series may be competing when the classification is updated.

The Bowbells, Brycan, Carfall, Center Creek, Fiesta, Flaxton, Hereford, Hesperus, Laceycreek, Ohwiler, Pachel, Peta, Schauson, Todacheene, Trag, and Weed soils do not have a lithic or paralithic contact above 60 inches.

The Chugcreek soils have a lithic contact with granite between 20 and 40 inches.

GEOGRAPHIC SETTING:
Parent material: slope alluvium, or eolian deposits, over residuum derived from sedimentary rocks
Landform: hills, hillslopes, toeslopes, mesas, and mountain slopes
Slopes: 0 to 40 percent
Elevation: 6,000 to 8,500 feet
Mean annual temperature: 39 to 47 degrees F
Mean annual summer temperature: 62 to 70 degrees F.
Mean annual precipitation: 15 to 22 inches
Frost-free period: 60 to 120 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Mespun, Kolob, Paunsaugunt and Dalcan soils. Mespun soils lack argillic horizons and have sandy control sections. Kolob soils have argillic horizons with more than 35 percent coarse fragments. Paunsaugunt soils lack argillic horizons, have particle size control sections with more than 35 percent coarse fragments and are less than 20 inches deep to bedrock. Dalcan soils have more than 35 percent coarse fragments in the particle size control section and are 20 to 40 inches deep over bedrock.

DRAINAGE AND PERMEABILITY: Well drained, low to very high runoff, moderate or moderately slow permeability

USE AND VEGETATION: Used for rangeland, wildlife habitat and recreation areas. Vegetation is mountain big sagebrush, wild crab apple, Gambel's oak, pinyon pine, juniper, ponderosa pine, needleandthread and Poa species.

DISTRIBUTION AND EXTENT: Southern Utah and western Colorado. LRR D and E, MLRA 35, 47, 48A. This series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Washington County, Utah, 1972

REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon: The zone from 0 to 27 inches. (A, BA, and Bt1)
argillic horizon: The zone from 14 to 44 inches. (Bt1 and Bt2)
lithic contact: at 44 inches. (R)
Particle-size control section: The zone from 14 to 34 inches. (Bt1 and Bt2)
Prior to 2/99 this series included both deep and very deep soils.

The assignment of activity class is presumed based on the general trend of other soils in the area.

Keys to Soil Taxonomy: Classified according to the eighth Edition 1998

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National Cooperative Soil Survey
U.S.A.