LOCATION ARCHES                  UT+AZ CO NM

Established Series
Rev. DAL/RLT/MJD
08/2017

ARCHES SERIES

The Arches series consists of very shallow and shallow, well to excessively drained, rapidly permeable soils that formed in sandy eolian deposits and residuum derived from sandstone. These soils are on plateaus, benches, sand sheets on structural benches, cuestas, mesas, and hills with slopes of 2 to 60 percent. Average annual precipitation is 11 inches and mean annual air temperature is about 50 degrees F.

TAXONOMIC CLASS: Mixed, mesic Lithic Torripsamments

TYPICAL PEDON: Arches fine sand - rangeland. (Colors are for dry soil unless otherwise noted).

C1--0 to 4 inches; light reddish brown (5YR 6/4) fine sand, reddish brown (5YR 4/4) moist; single grain; loose; slightly calcareous; slightly alkaline (pH 7.8); clear smooth boundary. (2 to 4 inches thick)

C2--4 to 13 inches; light reddish brown (5YR 6/4) fine sand, reddish brown (5YR 4/4) moist; single grain; loose; common fine and few medium roots; moderately calcareous; moderately alkaline (pH 8.0); abrupt smooth boundary. (8 to 16 inches thick)

R--13 inches; red calcareous sandstone.

TYPE LOCATION: San Juan County, Utah; about 3.5 miles south, southeast of the confluence of the Green and Colorado Rivers; 2,000 feet north and 2,600 feet west of the SE corner of sec. 29, T. 30 S., R. 19 E.

RANGE IN CHARACTERISTICS:
Soil moisture: The soil is dry during May and June. Ustic aridic soil moisture regime
Mean annual soil temperature: 47 to 59 degrees F.
Depth to bedrock: 4 to 20 inches
Rock fragment content: 0 to 5 percent
Control section texture: sand, fine sand, loamy sand, loamy fine sand. The sands are dominantly fine or very fine with a small percentage of medium or coarse sand

C1 horizon
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 to 7 dry, 3 to 6 moist
Chroma: 2 to 6, dry or moist
Reaction: slightly alkaline or moderately alkaline
Noncalcareous to moderately calcareous
Calcium carbonate equivalent: 0 to 4 percent
Not present in all pedons

C2 horizon
Hue: 2.5YR, 5YR, 7.5YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 3 to 6, dry or moist
Noncalcareous to moderately calcareous
Calcium carbonate equivalent: 0 to 8 percent
Reaction: slightly alkaline to strongly alkaline
Other features: some pedons have thin Cr or Cd horizons above the lithic contact

COMPETING SERIES: These are Moclom (UT), Needle (AZ) and Schooner (WY) series.
Moclom soils have 10YR hues. Needle soils have a typic aridic soil moisture regime. Schooner soils are usually moist during May and June.

GEOGRAPHIC SETTING: Arches soils are on plateaus, structural benches, cuestas, mesas, ledges, and hills at elevations of 4,000 to 7,610 feet. Slopes are 2 to 60 percent. The soils formed in sandy eolian deposits and residuum derived from sandstone. The mean annual air temperature is 45 to 56 degrees F. and the average annual precipitation is 8 to 14 inches. The frost-free period is 110 to 210 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Leanto, Rizno, Ignacio, Begay, and Mespun soils. Rizno soils are loamy. Ignacio soils are moderately deep. Begay and Ignacio soils are coarse-loamy. Mespun and Begay soils are very deep.

DRAINAGE AND PERMEABILITY: Well drained to excessively drained, slow to rapid runoff; very rapid or rapid permeability above the bedrock.

USE AND VEGETATION: These soils are used mainly for livestock grazing, wildlife habitat, and recreation. Native vegetation is Indian ricegrass, galleta, blackbrush, Mormon-tea and Utah juniper.

DISTRIBUTION AND EXTENT: Southeastern Utah, northeastern Arizona, northwest New Mexico and western Colorado. The soils of this series are extensive. MLRAs are 35 and 36. This series is not to be correlated outside MLRA 35 and 36.

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

SERIES ESTABLISHED: Canyonlands Area, Grand and San Juan Counties, Utah, 1983.
Named after Arches National Park.

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

Lithic contact - the boundary with hard sandstone at 13 inches (R layer)

Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, 11th Edition, 2010.

Update and revisions for the correlation of Ft. Defiance Area (AZ715) and Navajo Mountain area, May 2008, CEM
Update and revisions for the correlation of Arches National Park (UT687), February 2009, CEM
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
Update and revisions for the correlation of Capitol Reef (UT685), January 2013, WWJ
Update and revisions for the correlation of Kane County (UT642), July 2017, CEM
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National Cooperative Soil Survey
U.S.A.