LOCATION CRITCHELL CO
Established Series
Rev. GB-KLS
05/2023
CRITCHELL SERIES
The Critchell series consists of deep, well drained soils that formed in mixed alluvium derived from reddish brown sedimentary rocks. Critchell soils are on fans, terraces, strike valleys and valley sideslopes. Slopes of 0 to 15 percent. The mean annual precipitation is about 430 mm, and the mean annual temperature is about 8 degrees C.
TAXONOMIC CLASS:Fine-loamy, mixed, superactive, mesic Aridic Argiustolls
TYPICAL PEDON:Critchell gravelly sandy loam, nonirrigated cropland. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 15 cm; very dark grayish brown (10YR 3/2) gravelly sandy clay loam, dark brown (10YR 3/3) moist; weak fine granular structure; slightly hard, very friable, slightly sticky; 15 to 20 percent pebbles; neutral (pH 7.0); clear smooth boundary. (10 to 20 cm thick)
BA--15 to 23 cm; dark grayish brown (10YR 4/2) gravelly sandy clay loam, very dark grayish brown (10YR 3/2) moist; weak coarse subangular blocky structure; hard, very friable, slightly sticky; very thin clay films on faces of peds; 15 to 25 percent gravel; neutral (pH 7.0); clear smooth boundary. (0 to 13 cm thick)
Bt1--23 to 38 cm; brown (7.5YR 4/2) gravelly sandy clay loam, dark brown (7.5YR 3/3) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; very hard, friable, sticky; moderately thick continuous clay films on faces of peds; 15 to 25 percent gravel; neutral (pH 7.2); clear smooth boundary.
Bt2--38 to 66 cm; reddish gray (5YR 5/2) gravelly sandy clay loam, reddish brown (5YR 4/3) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; very hard, friable, sticky; moderately thick continuous clay films on faces of peds; 15 to 25 percent gravel; neutral (pH 7.2); clear smooth boundary. (combined thickness of Bt horizons - 30 to 65 cm)
BC--66 to 89 cm; reddish brown (5YR 5/4) gravelly sandy clay loam, reddish brown (5YR 4/4) moist; weak moderate prismatic structure parting to weak moderate subangular blocky; very hard, friable, sticky; few thin clay films on the faces of peds; 20 to 30 percent gravel; neutral (pH 7.2); gradual smooth boundary. (0 to 25 cm thick)
C1--89 to 132 cm; light reddish brown (5YR 6/4) gravelly sandy loam, reddish brown (5YR 4/4) moist; weak coarse prismatic structure parting to weak coarse subangular blocky; hard, friable; 30 to 35 percent gravel; slightly alkaline (pH 7.6); gradual smooth boundary. (0 to 56 cm thick)
C2--132 to 152 cm; pink (5YR 7/4) gravelly coarse sandy loam, reddish brown (5YR 5/4) moist; massive; hard, very friable; 30 to 40 percent gravel; slightly alkaline (pH 7.6).
TYPE LOCATION:Jefferson County, Colorado; approximately 1,609 kilometers (or one mile) west of the spillway of Chatfield Dam; 23 meters east and 98 meters south of the center of sec. 2, T. 6 S., R. 69 W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 8.9 to 11 degrees C
Mollic epipedon thickness - 18 to 39 cm
Solum thickness - 61 to 122 cm
These soils are generally noncalcareous; but some pedons are calcareous below a depth of 100 cm
Particle-size control section (weighted average):
Clay content - 18 to 35 percent
Rock fragment content - 15 to 35 percent above 100 cm, consisting mainly of gravel, cobbles, and stones of sandstone lithology
Reaction - pH 6.6 to 7.8
A horizon
Hue: 10YR through 5YR
Value: 3 through 5 dry, 2 or 3 moist
Chroma: 2 or 3
Texture: sandy loam or loam
Bt horizon
Hue: 7.5YR through 2.5YR
Value: 3 through 6 dry, 3 or 4 moist
Chroma: 2 through 4
Texture: sandy clay loam, loam or clay loam
C horizon
Hue: 7.5YR through 2.5YR
Texture: sandy loam, sandy clay loam or loam.
Stratification may occur in the lower part of the solum.
COMPETING SERIES:
Ascalon (CO) - have horizons with secondary calcium carbonate accumulation
Belfon (KS) - have horizons with secondary calcium carbonate accumulation
Bresser (CO) - have less than 15 percent rock fragments in the particle-size control section; formed in arkose deposits or granite
Cedak (WY) - are moderately deep to paralithic contact
Charkiln (NV) - have an aridic soil moisture regime
Corralgulch (CO) - have horizons with secondary calcium carbonate accumulation
Dagflat (UT) - are moderately deep to lithic contact
Datil (NM) - have a calcic horizon
Featherlegs (NM) - have horizons with secondary calcium carbonate accumulation
Forgan (OK) - have a lithologic discontinuity
Hargreave (WY) - are moderately deep to paralithic contact
Harlan (WY) - have horizons with secondary calcium carbonate accumulation Hemmingford (NE) - are deep to paralithic contact
Hiarc (NM) - are moderately deep to paralithic contact
Kirtley (WY) - have horizons with secondary calcium carbonate accumulation; are moderately deep to paralithic contact
Lavate (UT) - have less than 15 percent rock fragments in the particle-size control section
Loarc (NM) - have horizons with secondary calcium carbonate accumulation
Moskee (WY) - have horizons with secondary calcium carbonate accumulation
Noden (WY) - have less than 15 percent rock fragments in the particle-size control section; have an aridic soil moisture regime
Palmer Canyon (WY) - have horizons with secondary calcium carbonate accumulation
Recluse (WY) - have horizons with secondary calcium carbonate accumulation
Satanta (KS) - have horizons with secondary calcium carbonate accumulation
Shalona (CO) - have horizons with secondary calcium carbonate accumulation
Sitcan (CO) - have horizons with secondary calcium carbonate accumulation
Sugardee (WY) - have horizons with secondary calcium carbonate accumulation
Wages (CO) - have horizons with secondary calcium carbonate accumulation
Wolf (WY) - have a calcic horizon
GEOGRAPHIC SETTING:
Landform - alluvial fans, terraces, strike valleys and valley side slopes
Elevation - 1,600 to 2,275 meters
Slopes - 0 to 15 percent
Parent material - mixed alluvium derived from reddish brown sedimentary rocks
Mean annual air temperature - 8 to 10 degrees C
Mean annual precipitation - 380 to 480 mm
Precipitation pattern - peak periods of precipitation occur during the spring and summer months
Frost-free period - 110 to 140 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY:Well-drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION:Soils are used for grazing land or as dry and irrigated cropland. Native vegetation is mainly blue grama, western wheatgrass, and some sagebrush, rabbitbrush, pinyon and juniper.
DISTRIBUTION AND EXTENT:Critchell soils are of small extent in the foothills along the eastern front of the Rocky Mountains in central Colorado; MLRA 49.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED:Jefferson County, Colorado, 1980, Golden Area Soil Survey.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 38 cm (Ap, BA, and Bt1 horizons)
Argillic horizon - 23 to 66 cm (Bt1 and Bt2 horizons)
Particle-size control section - 23 to 66 cm (Bt1 and Bt2 horizons)
Critchell soils have a mesic temperature regime and an ustic soil moisture regime bordering on aridic.
Converted to metric, formatting updated to current standards, and competing series section updated. 12/2020
National Cooperative Soil Survey
U.S.A.