LOCATION ARBOLES CO+NM UT
Established Series
Rev. JPP-TWH-KLS
02/2018
ARBOLES SERIES
The Arboles series consists of very deep, well drained soils that formed in fine textured slope alluvium derived from sandstone and shale. These soils are on pediments. Slopes range from 0 to 15 percent. Mean annual precipitation is about 350 mm, and mean annual temperature is about 8.9 degrees C.
TAXONOMIC CLASS: Fine, smectitic, mesic Aridic Haplusterts
TYPICAL PEDON: Arboles clay, on a west facing, 2 percent slope in cropland at an elevation of 2,063 meters. When described on July 21, 1980 the soil was dry from 0 to 152 cm. (Colors are for dry soil unless otherwise noted.)
Ap1--0 to 3 cm; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate fine granular structure; slightly hard, friable, moderately sticky and moderately plastic; slightly alkaline (pH 7.6); clear smooth boundary.
Ap2--3 to 15 cm; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate medium subangular blocky structure parting to moderate fine angular blocky; very hard, friable, moderately sticky and moderately plastic; slightly alkaline (pH 7.6); clear smooth boundary. (combined thickness of Ap1, Ap2 - 6 to 20 cm)
Bss1--15 to 30 cm; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate medium angular blocky structure parting to moderate fine angular blocky; very hard, very friable; moderately sticky and moderately plastic; common distinct pressure faces and slickensides on vertical faces of peds; slightly alkaline (pH 7.7); clear smooth boundary.
Bss2--30 to 58 cm; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate coarse angular blocky structure parting to strong fine angular blocky; very hard, firm, very sticky and very plastic; many prominent pressure faces and slickensides on vertical faces of peds; slightly alkaline (pH 7.8); clear smooth boundary.
Bss3--58 to 76 cm; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate, coarse, angular blocky structure parting to moderate medium angular blocky; very hard, firm, very sticky and very plastic; many prominent pressure faces and slickensides on vertical faces of peds; slightly effervescent; trace calcium carbonate equivalent; moderately alkaline (pH 8.2); clear smooth boundary. (combined thickness of Bss1, Bss2, Bss3 - 50 to 80 cm)
Bk--76 to 94 cm; brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; massive; hard, friable; moderately sticky and moderately plastic; strongly effervescent; trace calcium carbonate equivalent; moderately alkaline (pH 8.3); clear smooth boundary. (13 to 38 cm thick)
C1--94 to 117 cm; brown (7.5YR 5/4) clay loam, brown (10YR 4/3) moist; massive; hard, friable, moderately sticky moderately plastic; slightly effervescent; trace calcium carbonate equivalent; moderately alkaline (pH 8.3); clear smooth boundary. (greater than 15 cm thick)
C2--117 to 152 cm; reddish yellow (7.5YR 6/6) clay loam, brown (7.5YR 5/4) moist; weak medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; slightly effervescent in spots; trace calcium carbonate equivalent; moderately alkaline (pH 8.2)
TYPE LOCATION: La Plata County, Colorado, about 17.7 kilometers southeast of Durango, Colorado. Located about 30.5 m north and 15 m west of the southeast corner of Sec. 9, T. 34 N., R. 8 W. U.S.G.S. Gem Village quad.; Lat. 37 degrees, 13 minutes, 22 seconds N., and Long. 107 degrees, 44 minutes, 30 seconds W.
RANGE IN CHARACTERISTICS:
Soil moisture regime: Ustic bordering on aridic
Number of days cracks are open (cumulative): 90 to 150
Soil temperature regime: mesic
Mean annual soil temperature: 8.9 to 11.0 degrees C.
Mean summer soil temperature: 15.5 to 18.3 degrees C.
Depth to carbonates: 0 to 60 cm
Vertic features: The soil has cracks extending to the surface when dry. Cracks are 1 to 3 cm wide and 50 cm or more deep, and 30 cm or more long, and remain open 90 to 150 cumulative days in most years. The COLE value is about 0.07 in the surface layer and 0.06 cm/cm in the Bss horizons.
Base saturation: 94 to 97 percent by sum of the bases throughout the soil.
Particle size control section, weighted average:
Clay content: 40 to 55 percent
Rock fragment content: 0 to 5 percent
A horizons:
Hue: 7.5YR to 2.5Y
Value: 5 to 7 dry, 3 to 6 moist
Chroma: 2 to 4 dry or moist
Texture: clay, clay loam
Reaction: 6.6 to 7.8
Note: Surface horizons that have value as dark as 5 dry and 3 moist are too thin to be mollic epipedons.
Bss horizons:
Hue: 7.5YR to 2.5Y
Value: 5 to 7 dry, and 4 to 6 moist
Chroma: 2 to 5 dry or moist
Texture: clay, silty clay
Rock fragment content: 0 to 5 percent
Calcium carbonate equivalent: 0 to 5 percent
Reaction: 6.6 to 8.4
Bk horizons:
Hue: 7.5YR to 2.5Y
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 2 to 5, dry or moist
Texture: clay loam, clay, silty clay
Rock fragment content: 0 to 5 percent
Calcium carbonate equivalent: trace to 15 percent
Reaction: 7.4 to 8.4
C horizons:
Hue: 7.5YR to 2.5Y
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 2 to 6 dry or moist
Texture: clay loam, silty clay, clay
Rock fragment content: 0 to 5 percent
Calcium carbonate equivalent: 0 to 10 percent
Reaction: 7.4 to 8.4
COMPETING SERIES:
Albers (AZ) - have rock fragments that include volcanic lithology
Antelopeflat (CO) - have accumulations of secondary gypsum
Dominguez (CO) - have hue redder than 7.5YR in the B horizon
Ritoazul (CO) - moderately deep to paralithic contact
Sideshow (CO) - have accumulations of secondary gypsum
Springerville (AZ) - deep to a lithic contact
GEOGRAPHIC SETTING:
Landform - pediments
Elevation - 1,525 to 2,135 meters
Slope - 0 to 15 percent
Parent Material - slope alluvium derived from sandstone and shale
Mean annual precipitation - 325 to 400 mm, but can range up to 450 mm in some areas
Mean annual air temperature - 7.2 to 10.0 degrees C.
Mean summer air temperature - 18.3 to 20.0 degrees C.
Precipitation pattern - about half the precipitation occurs April through September, with May and June being the driest months.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; very slow to slow permeability.
USE AND VEGETATION: These soils are used mainly for irrigated crops and pastureland. Some areas are used for dryland crops and native rangeland. Small grains, such as barley and oats, and alfalfa are the principal crops in irrigated areas. Wheat is the principal dryland crop. Native vegetation consists mainly of Indian ricegrass, muttongrass, Junegrass, western wheatgrass, big sagebrush, a few pinyon, and Utah juniper.
DISTRIBUTION AND EXTENT: Arboles soils occur in Western Colorado and parts of Utah and New Mexico; LLR D, MLRA 36; moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: La Plata County, Colorado, 1982.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Cambic horizon: the zone from 15 to 76 cm (Bss1, Bss2, Bss3 horizons)
Vertic features: cracks common to Vertisols, and pressure faces and slickensides from 15 to 76 cm (Bss1, Bss2, Bss3 horizons)
Particle-size control section: from 25 to 100 cm (part of Bss1, Bss2, Bss3, Bk, part of C1 horizons)
ADDITIONAL DATA: Soil sampled for characterization in 1980. NSSL Sample number is S80-CO-067-001.
National Cooperative Soil Survey
U.S.A.