LOCATION ADDERTON COEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Cumulic Haplocryolls
TYPICAL PEDON: Adderton loam - on a 2 percent slope in an area of rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 3 inches; dark grayish brown (10YR 4/2) loam, black (10YR 2/1) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; 10 percent gravel, 2 percent cobbles; neutral (pH 7.2); abrupt smooth boundary.
A2--3 to 12 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; neutral (pH 7.2); abrupt smooth boundary.
A3--12 to 20 inches; dark grayish brown (10YR 4/2) stratified sandy loam and loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; slightly alkaline (pH 7.6); abrupt smooth boundary.
A4--20 to 27 inches; dark grayish brown (10YR 4/2) loam, black (10YR 2/1) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; 10 percent gravel, 2 percent cobbles; neutral (pH 7.2); abrupt smooth boundary.
A5--27 to 34 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; 10 percent gravel; slightly effervescent in spots; slightly alkaline (pH 7.6); abrupt smooth boundary.
A6--34 to 39 inches; very dark gray (10YR 3/1) silty clay loam, black (10YR 2/1) moist; weak medium prismatic structure; hard, firm, very sticky and very plastic; slightly alkaline (pH 7.6); abrupt smooth boundary.
A7--39 to 49 inches; grayish brown (10YR 5/2) loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; 5 percent gravel; slightly alkaline (pH 7.6); abrupt smooth boundary. (combined thickness of the A horizon is 20 to 60 or more inches)
2C--49 to 60 inches; brown (10YR 5/3) very gravelly loamy sand, dark brown (10YR 3/3) moist; single grain; loose, nonsticky and nonplastic; 50 percent gravel; slightly alkaline (pH 7.8).
TYPE LOCATION: Fremont County, Colorado; about 11 miles north of Cotopaxi; about 3,000 feet south and 1,850 feet west of the northeast corner of Sec. 6, T. 49 N., R. 12 E. U.S.G.S. Waugh Mountain Quad., Lat. 38 degrees, 31 minutes, 32 seconds N., and Long. 105 degrees, 41 minutes, 16 seconds W.
RANGE IN CHARACTERISTICS:
Soil moisture: usually dry in some part in early summer, then intermittently moist in late summer and fall; ustic moisture regime.
Mean annual soil temperature: 37 to 46 degrees F.
Mean summer soil temperature: 51 to 58 degrees F.
Thickness of the mollic epipedon: 16 to 60 or more inches
Depth to lithologic discontinuity (2C horizon): greater than 40 inches
Particle-size control section (weighted averages):
Clay content: 18 to 35 percent
Silt content: 25 to 45 percent
Sand content: 25 to 45 percent
Rock fragment content: 0 to 10
A horizons:
Hue: 10YR or 7.5YR
Value: 3 through 5 dry, 2 or 3 moist
Chroma: 1 through 3
Texture, fine earth fraction: loam, silty clay loam, clay loam; includes thin strata of sandy loam, fine sandy loam, sandy clay loam, or silty clay loam
Rock fragment content: 0 to 35 percent
Reaction: neutral or slightly alkaline
C horizon (present in some pedons):
Hue: 10YR or 7.5YR
Value: 3 through 5 dry, 3 or 4 moist
Chroma: 2 through 4
Texture: sandy loam
Clay content: 5 to 18 percent
Rock fragment content: 0 to 10 percent
Reaction: neutral or slightly alkaline
2C horizon :
Hue: 10YR or 7.5YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 or 3
Rock fragments: 50 percent or more in some pedons
Texture: very gravelly loamy sand, very gravelly sandy loam
Reaction: neutral or slightly alkaline
COMPETING SERIES:
Lanswick (CO) aridic-ustic soil moisture regime
Middlecreek - does not have a lithologic discontinuity
Mussigbrod - has secondary carbonates
Silas (WY) - has endosaturation
GEOGRAPHIC SETTING: Adderton soils are on flood plains, flood-plain steps, stream terraces, alluvial fans, and toe slopes. Slopes range from 1 to 15 percent. The soil formed in alluvium derived from intrusive rocks, sedimentary rocks, and volcanic rocks. Elevation ranges from 7,000 to 10,200 feet. The mean annual precipitation ranges from 14 to 24 inches with peak periods of precipitation occurring in July and August. Mean annual temperature ranges from 37 to 44 degrees F. The frost-free period is about 50 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bushpark, Quander, Granile, Hoodle, Seitz, and Tellura soils. Bushpark soils are shallow. Quander, Granile, Hoodle, Seitz, and Tellura soils consist of a high content of coarse fragments, and Granile and Seitz soils also lack mollic epipedons.
DRAINAGE AND PERMEABILITY: Well drained; low to high runoff; moderately slow or moderate permeability (moderately high Ksat).
USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. Native vegetation consists of Arizona fescue, mountain muhly, Parry's oatgrass, prairie junegrass, and western wheatgrass.
DISTRIBUTION AND EXTENT: Mountain valleys of Colorado; MLRA 48A. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Fremont County, (Fremont County Area), Colorado, 1988.
REMARKS: Diagnostic features include:
Mollic epipedon (Cumulic feature)- from 0 to 49 inches (all the A horizons); an irregular decrease in organic carbon is inferred from the texture stratification.
The soil has a typic ustic moisture regime and a cryic temperature regime.