LOCATION ROUTT CO+ID WY
Established Series
Rev. MLP/NHK
10/2026
ROUTT SERIES
The Routt series consists of very deep, well drained soils that formed in colluvium or slope alluvium, derived from sedimentary rock or slide deposits; some with loess influence. Routt soils are on plateaus, hills, landslides, and mountain slopes. Slopes are 3 to 75 percent. Mean annual precipitation is about 650 mm and mean annual temperature is about 3.0 degrees C.
TAXONOMIC CLASS: Fine, smectitic Pachic Palecryolls
TYPICAL PEDON: Routt loam in cropland. (Colors are for dry soil unless otherwise noted.)
Ap1--0 to 5 cm; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to weak fine granular; soft, very friable, slightly sticky and slightly plastic; neutral (pH 6.8); abrupt smooth boundary.
Ap2--5 to 28 cm; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to weak fine subangular blocky; soft, very friable, slightly sticky and slightly plastic; neutral (pH 6.8); abrupt smooth boundary.
A1--28 to 46 cm; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; neutral (pH 6.8); clear smooth boundary.
A2--46 to 64 cm; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; neutral (pH 6.8); gradual smooth boundary.
B/E--64 to 71 cm; 70 percent yellowish brown (10YR 5/4) and 30 percent pale brown (10YR 6/3) clay loam, dark yellowish brown (10YR 4/4) and brown (10YR 5/3) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; hard, friable, sticky and plastic; neutral (pH 7.0); clear smooth boundary.
Bt1--71 to 89 cm; yellowish brown (10YR 5/4) clay, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; very hard, firm, very sticky and very plastic; neutral (pH 7.0); gradual smooth boundary.
Bt2--89 to 114 cm; light yellowish brown (10YR 6/4) clay, yellowish brown (10YR 5/4) moist; moderate medium subangular blocky structure parting to weak fine subangular blocky; very hard, firm, very sticky and very plastic; neutral (pH 7.3); gradual smooth boundary.
Bt3--114 to 150 cm; brownish yellow (10YR 6/6) clay, dark yellowish brown (10YR 4/6) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; very hard, firm, very sticky and very plastic; slightly alkaline (pH 7.4).
TYPE LOCATION: Routt County, Colorado; USGS Cow Creek topographic quadrangle; latitude 40.48417 degrees north, longitude 106.92361 degrees west, datum WGS84.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--0.6 to 2.8 degrees C[KN-NIFI1.1][CR1.2]
Thickness of mollic epipedon--50 to 76 cm
Depth to argillic--61 to 150 cm
Particle-size control section (weighted averages)
Clay content--35 to 50 percent
Oi (when present)
Texture--slightly decomposed plant material
Reaction--pH 4.0 to 6.5
Thickness--0 to 3 cm
A horizons
Hue--10YR to 2.5Y
Value--2 moist, 3 to 5
Chroma--1 to 3
Texture (less than 2 mm fraction)--silt loam, loam
Clay content--14 to 24 percent
Rock fragments--0 to 5 percent gravel
Reaction--pH 6.1 to 7.3
Thickness--5 to 27 cm
B/E horizon
Hue--10YR to 2.5Y
Value--3 to 6 moist, 5 to 8 dry
Chroma--3 to 6
Texture (less than 2 mm fraction)--loam or clay loam
Clay content--18 to 40
Rock fragments--0 to 15 percent - 0 to 10 percent gravel, 0 to 5 percent cobbles
Reaction--pH 6.1 to 7.3
Thickness--0 to 18 cm
Bt horizons
Hue--7.5YR to 2.5Y
Value--5 or 6 dry, 4 or 5 moist
Chroma--3 to 6
Texture (less than 2 mm fraction)--silty clay loam, clay loam, silty clay, or clay
Clay content--30 to 55
Rock fragments--0 to 25 percent - 0 to 515 percent gravel, 0 to 5 percent cobbles
Reaction--pH 5.6 to 6.5
COMPETING SERIES:
Everman(UT)--soils have a slightly or moderately calcareous lithologic discontinuity
GEOGRAPHIC SETTING:
Landform--plateaus, hills, landslides, and mountain slopes
Elevation--1,830 to 2,600 meters
Slope--3 to 75 percent
Parent material--loess, colluvium, slope alluvium, and residuum from sedimentary rock
Climate--long, cold winters; cool, moist springs; short, cool summers
Mean annual precipitation--410 mm to 850 mm
Mean annual air temperature--0.6 to 4.4 [CR2.1]degrees C
Frost-free period--30 to 75 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained, 0.5 to 1.5 um/sec
USE AND VEGETATION: Routt soils are primarily used for grazing, cropland, wildlife, and recreation. The potential native vegetation is gambel oak, quaking aspen, mountain snowberry, mountain big sage, bromegrasses, needlegrass, and wheatgrass.
DISTRIBUTION AND EXTENT: Routt soils are of moderate extent in northwestern and north-central area of Colorado and in southeast Idaho.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Moffat County, Colorado; 1991.
REMARKS: Diagnostic horizons and features recognized in the pedon:
Mollic epipedon--0 to 64 cm (Ap1, Ap2, A1, and A2 horizons)
Argillic horizon--71 to 150 cm (Bt1 and Bt2 horizons)
Particle-size control section--71 to 121 cm
Routt soils have a cryic temperature regime and an udic moisture regime.
Taxonomic version: Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.