LOCATION CHRIS CO
Established Series
Rev. JPP/TWH/KLS
03/2018
CHRIS SERIES
The Chris series consists of very deep, well drained soils that formed in slope alluvium or colluvium derived from sedimentary rocks. Chris soils are on mountain slopes, valley sideslopes, and canyon sideslopes. Slopes range from 9 to 70 percent. Mean annual precipitation is about 914 mm and the mean annual temperature is about 3.3 degrees C.
TAXONOMIC CLASS: Clayey-skeletal, mixed, superactive Eutric Glossocryalfs
TYPICAL PEDON: Chris gravelly loam, on a west facing, simple, 35 percent slope in spruce-fir woodland at an elevation of 2,987 meters. (Colors are for dry soil unless otherwise noted.) Described on July 16, 1990.
Oi--0 to 3 cm; organic layer of partly decomposed needles and leaves. (0 to 10 cm thick)
E--3 to 33 cm; pinkish gray (7.5YR 6/2) gravelly loam, brown (7.5YR 5/2) moist; moderate fine granular structure; soft, very friable, non sticky and non plastic; 15 percent gravel, 3 percent cobble and 1 percent stones; neutral (pH 7.2); clear wavy boundary. (10 to 36 cm thick)
E/B--33 to 58 cm; 60 percent E, pinkish gray (5YR 6/2) gravelly sandy clay loam, reddish gray (5YR 5/2) moist, and 40 percent B, light reddish brown (5YR 6/3) gravelly clay loam, reddish brown (5YR 5/3) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; 20 percent gravel, 10 percent cobble and 2 percent stones; neutral (pH 6.8); clear wavy boundary. This horizon consists of tongues of albic materials extending into the underlying material. (0 to 30 cm thick)
B/E--58 to 79 cm; 80 percent B, light reddish brown (5YR 6/4) very cobbly clay loam, reddish brown (5YR 4/4) moist, and 20 percent E, pinkish gray (5YR 6/2) very cobbly loam, reddish gray (5YR 5/2) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common distinct clay films on faces of peds of the B part; 20 percent gravel, 30 percent cobble and 5 percent stones; slightly acid (pH 6.2); gradual wavy boundary. (8 to 30 cm thick)
Bt--79 to 107 cm; light reddish brown (5YR 6/4) very cobbly clay loam, yellowish red (5YR 4/6) moist; moderate medium angular and subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common prominent clay films on faces of peds; 20 percent gravel, 30 percent cobble and 5 percent stones; moderately acid (pH 6.0); gradual wavy boundary. (20 to 102 cm thick)
C--107 to 155 cm; light reddish brown (5YR 6/4) very cobbly sandy clay loam, reddish brown (5YR 5/4) moist; massive; hard, friable, slightly sticky and moderately plastic; 20 percent gravel, 30 percent cobble and 10 percent stones; moderately acid (pH 6.0).
TYPE LOCATION: Archuleta County, Colorado; about 15 miles northeast of Bayfield, Colorado; located about 975 meters W and 244 meters S of the northeast corner of Sec. 25, T. 36 N., R. 6 W.; Baldy Mountain USGS quad; Lat. 37 degrees 21 minutes 47 seconds N., Long. 107 degrees 28 minutes 53 seconds W., NAD 27.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 2.2 to 4.4 degrees C.
Mean summer soil temperature - 10.0 to 12.2 degrees C. (without O horizon)
Base saturation is over 50 percent in all parts from the mineral soil surface to a depth of 180 cm.
Particle-size control section:
Clay content - 35 to 50 percent
Rock fragment content - 35 to 60 percent consisting mostly of sandstone fragments
E horizon
Hue: 2.5YR to 10YR
Value: 5 to 8 dry, 4 to 7 moist
Chroma: 1 to 3, dry and moist
Rock fragment content: 15 to 65 percent; gravel, cobbles and/or stones
Reaction (pH): 5.6 to 7.3
The E/B horizon
E part:
Hue: 2.5YR to 7.5YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 1 to 3, dry and moist
Texture, fine earth fraction: L, SCL
Rock fragment content: 15 to 60 percent; gravel, cobble and/or stones
B part:
Hue: 2.5YR or 5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 to 6, dry and moist
Texture, fine earth fraction: CL, SCL
Rock fragment content: 15 to 60 percent; gravel, cobble and/or stones
Reaction (pH): 5.6 to 7.3
The B/E horizon
B part:
Hue: 2.5YR or 5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 to 6, dry and moist
Texture, fine earth fraction: SCL, CL, C
Rock fragment content: 15 to 60 percent; gravel, cobble and/or stones
E part:
Hue: 2.5YR or 5YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 1 to 3, dry and moist
Texture, fine earth fraction: L, SCL
Rock fragment content: 15 to 60 percent; gravel cobble and/or stones
Reaction (pH): 5.6 to 7.3
Bt horizon
Hue: 10R to 5YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 2 to 6, dry and moist
Texture, fine earth fraction: CL, C
Rock fragment content: 35 to 60 percent; gravel cobble and/or stones
Reaction (pH): 5.6 to 6.5
C horizon
Hue: 10R to 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 to 6, and moist
Texture, fine earth fraction: SCL, CL, or L
Rock fragment content: 35 to 60 percent; gravel cobble and/or stones
Reaction (pH): 5.6 to 7.3
COMPETING SERIES:
Relyea (MT) - have horizons with secondary carbonate accumulation.
GEOGRAPHIC SETTING:
Landform - mountain slopes, valley sideslopes, and canyon sideslopes
Elevation - 2,590 to 3,110 meters
Slopes - 9 to 70 percent
Parent material - slope alluvium or colluvium derived from sedimentary rocks, mainly sandstone
Mean annual air temperature - 1.1 to 4.4 degrees C.
Mean annual precipitation - 635 to 1,015 mm
Precipitation pattern: wettest months are July and August; driest months are May and June receive the least precipitation, however the soils are still moist from snowmelt.
Frost-free period: 60 to 80 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; medium or high runoff; slow permeability.
USE AND VEGETATION: These soils are used for timber production, livestock grazing, wildlife habitat, and recreation. Native vegetation is mainly white fir, Engelmann's spruce, subalpine fir, ponderosa pine, Myrtle whortelberry, Arizona fescue, Gambel's oak, and mountain brome.
DISTRIBUTION AND EXTENT: Southwestern Colorado. LRR E, MLRA 48A; moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Hinsdale County (Piedra area) Colorado, 1974.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Albic horizon: 3 to 33 cm (E horizon)
Glossic horizon: 33 to 79 cm (E/B and B/E horizons)
Argillic horizon: 58 to 107 cm (B/E and Bt horizons)
Particle-size control section: 58 to 107 cm (B/E and Bt horizons)
Chris soils are in a cryic temperature regime and a udic soil moisture regime with a typic subclass.
National Cooperative Soil Survey
U.S.A.