LOCATION XETO CO
Established Series
Rev. JPP/KLS
04/2018
XETO SERIES
The Xeto series consists of moderately deep, somewhat excessively well drained soils that formed in slope alluvium or colluvium over residuum derived from sandstone and shale. Xeto soils are on hills and paleoterrace risers. Slopes range from 12 to 60 percent. Mean annual precipitation is about 356 mm and the mean annual air temperature is about 8.9 degrees C.
TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Aridic Calciustepts
TYPICAL PEDON: Xeto extremely cobbly loam, on a northeast facing, simple, 40 percent slope in pinyon-juniper at an elevation of 1,890 meters. (Colors are for dry soil unless otherwise noted.) When described on March 22, 2005 the soil was moist from 0 to 79 cm. The surface is covered with about 10 percent cobbles.
A--0 to 13 cm; grayish brown (10YR 5/2) extremely cobbly loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; soft, friable, slightly sticky, slightly plastic; many fine and very fine roots throughout; few fine tubular pores; 25 percent gravel, 40 percent cobbles, 1 percent stones; slightly effervescent; slightly alkaline (pH 7.4); clear smooth boundary. (5 to 18 cm thick)
Bk1--13 to 51 cm; pale brown (10YR 6/3) extremely cobbly loamy sand, brown (10YR 4/3) moist; weak medium granular structure; soft, very friable, nonsticky, nonplastic; common fine and very fine roots throughout; few fine tubular pores; 13 percent calcium carbonate finely disseminated throughout and carbonate masses on the bottom of rock fragments; 20 percent gravel, 40 percent cobbles, 1 percent stones; violently effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (15 to 61 cm thick)
Bk2--51 to 79 cm; pale brown (10YR 6/3) extremely cobbly sand, brown (10YR 4/3) moist; single grain; loose, loose, nonsticky, nonplastic; few very fine roots throughout; 5 percent calcium carbonate finely disseminated throughout and carbonate masses on the bottom of rock fragments; 25 percent gravel, 40 percent cobbles, 1 percent stones; strongly effervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (0 to 38 cm thick)
Cr--79 to 104 cm; shale bedrock; neutral.
TYPE LOCATION: Archuleta County, CO; about 5 kilometers north of Arboles; located about 274 meters south and 762 meters west of the northeast corner of Section 5, T 32 N., R 5 W.; USGS Allison topographic quadrangle, NAD27; Lat. 37 degrees, 3 minutes, 3 seconds N. and Long. 107 degrees, 24 minutes, 53 seconds W., NAD 27.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 10.0 to 11.7 degrees C.
Depth to paralithic contact: 50 to 100 cm
Depth to calcic horizon: 5 to 18 cm
Thickness of the calcic horizon: 33 to 97 cm
Particle-size control section:
Clay content: 3 to 10 percent
Sand content: 80 to 95 percent
Rock fragments: 35 to 75 percent
A horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 2 or 3, dry or moist
Texture: loam
Clay content: 15 to 25 percent
Rock fragments: 15 to 35 percent gravel, 15 to 55 percent cobbles, 0 to 10 percent stones
Reaction (pH): 6.6 to 7.8
Bk horizon, upper part
Hue: 7.5YR or 10YR
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 to 4 dry or moist
Texture: loamy sand, sand
Clay content: 5 to 10 percent
Rock fragments: 10 to 40 percent gravel, 10 to 50 percent cobbles, 0 to 15 percent stones
Calcium carbonate equivalent: 5 to 25 percent
Reaction (pH): 7.9 to 8.4
Bk horizon, lower part
Hue: 7.5YR or 10YR
Value: 5 or 7 dry; 4 to 6 moist
Chroma: 2 to 4, dry or moist
Texture: loamy sand, sand
Clay content: 2 to 10 percent
Rock fragments: 5 to 50 percent gravel, 5 to 50 percent cobbles, 0 to 15 percent stones
Calcium carbonate equivalent: 5 to 15 percent
Reaction: 7.9 to 8.4
COMPETING SERIES:
Encantado (NM) - are very deep
Yuzarra (NM) - have lithology of Precambrian granite, gneiss, and schist; are over residuum derived from Tertiary granitic sandstone and fanglomerate.
GEOGRAPHIC SETTING:
Landform - hills, risers of paleoterraces
Elevation - 1,830 to 2,404 meters
Slopes - 12 to 60 percent
Parent material - slope alluvium or colluvium over residuum derived from sandstone and shale
Mean annual temperature - 8.3 to 10.0 degrees C.
Mean annual precipitation - 330 to 410 mm
Precipitation pattern - wettest months are July and August; driest months are May and June
Frost-free period - 110 to 130 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Somewhat excessively well drained, moderate runoff, moderate permeability in the surface and rapid in the layers below the surface.
USE AND VEGETATION: Used for wildlife habitat and livestock grazing. Native vegetation is twoneedle pinyon, Utah juniper, big sagebrush, blue grama, Indian ricegrass, and Junegrass
DISTRIBUTION AND EXTENT: Southwestern Colorado. LRR D, MLRA 36. This series is of minor extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Archuleta County, CO, Archuleta soil survey area, 2005. The name is coined.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Calcic horizon - 25 to 79 cm (Bk horizons)
Paralithic contact - 79 cm to bedrock (Cr horizon)
Particle size control section - 25 to 79 cm (part of the Bk1 and the Bk2 horizons)
Xeto soils have a mesic temperature regime and are in an ustic soil moisture regime bordering on aridic.
National Cooperative Soil Survey
U.S.A.