LOCATION HODDEN COEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Calcic Argicryolls
TYPICAL PEDON: Hodden gravelly loam - on a 3 percent southwest-facing slope in an area of rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 4 inches; brown (7.5YR 4/2) gravelly loam, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; 20 percent gravel, 1 percent cobbles; neutral (pH 7.0); abrupt smooth boundary. (3 to 5 inches thick)
Bt1--4 to 10 inches; brown (7.5YR 4/2) very gravelly loam, dark brown (7.5YR 3/2) moist; moderate medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common prominent clay films on ped faces and lining pores; 40 percent gravel, 1 percent cobbles; neutral (pH 7.0); abrupt smooth boundary.
Bt2--10 to 13 inches; strong brown (7.5YR 4/6) very gravelly clay loam, dark brown (7.5YR 3/4) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common prominent clay films on ped faces and lining pores; 45 percent gravel, 1 percent cobbles; slightly alkaline (pH 7.4); abrupt smooth boundary. (combined thickness of the Bt horizons is 6 to 13 inches)
Bk1--13 to 16 inches; brown (7.5YR 5/4) very gravelly sandy clay loam, brown to brown (7.5YR 4/4) moist; weak fine subangular blocky structure; hard, very friable, slightly sticky and slightly plastic; many medium soft masses of calcium carbonate; violently effervescent; 45 percent gravel, 10 percent cobbles; moderately alkaline; abrupt smooth boundary. (0 to 10 inches thick)
Bk2--16 to 32 inches; pinkish white (7.5YR 8/2) very gravelly sandy loam, pink (7.5YR 7/4) moist; massive; slightly hard, very friable, slightly sticky and nonplastic; calcium carbonates disseminated and in many large soft masses; violent effervescence; 45 percent gravel, 10 percent cobbles; moderately alkaline; clear smooth boundary.
Bk3--32 to 44 inches; pink (7.5YR 7/4) very gravelly sandy loam, brown (7.5YR 5/4) moist; massive; slightly hard, very friable, slightly sticky and nonplastic; disseminated and few medium soft masses of calcium carbonate; violently effervescent; 45 percent gravel, 10 percent cobbles; moderately alkaline (pH 8.2); clear wavy boundary. (Combined thickness of the Bk2 and Bk3 horizons is 10 to 45 inches.)
2Bk4--44 to 60 inches; pinkish gray (7.5YR 7/2) extremely gravelly loamy sand, brown (7.5YR 5/2) moist; single grain; loose, nonsticky and nonplastic; coatings of calcium carbonate on undersides of rock fragments; slight effervescent; 65 percent gravel, 5 percent cobbles; moderately alkaline (pH 8.0). (0 to 24 inches thick)
TYPE LOCATION: Fremont County, Colorado; about 15 miles northeast of Salida; about 1,350 feet east and 1,580 feet north of the southwest corner of Sec. 6, T. 51 N., R. 11 E. U.S.G.S. Gribbles Park quad.; Lat. 38 degrees, 41 minutes, 33 seconds N., and Long. 105 degrees, 48 minutes, 29 seconds W.
RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 37 to 45 degrees F., and mean summer soil temperature ranges from 51 to 58 degrees F. The soil moisture control section is usually dry in late spring and early summer, moist in some part in late July and August, and intermittently dry in fall; ustic regime bordering on aridic.
Thickness of the mollic epipedon ranges from 7 to 14 inches. Depth to secondary calcium carbonate, depth to calcic horizon, and depth to the base of the argillic horizon ranges from 8 to 20 inches. Rock fragments in the Bt, Bk, and 2Bk horizons are mainly gravel, cobbles, and channers. These horizons have 25 to 65 percent gravel, 0 to 45 percent cobbles, and 0 to 10 percent stones.
Particle-size control section (weighted average):
Noncarbonate clay content: 18 to 35 percent
Sand content: 30 to 60 percent
Rock fragments: 35 to 60 percent
The A horizon has hue of 7.5YR or 10YR, value of 3 to 5 dry, 2 or 3 moist, and chroma of 2 or 3. Reaction is slightly acid to slightly alkaline. The fine-earth fraction is loam or sandy loam.
The Bt horizon has hue of 7.5YR or 10YR, value of 4 through 6 dry, 2 through 5 moist, and chroma of 2 through 6. Rock fragment content ranges from 35 to 65 percent. The fine-earth fraction is loam, sandy clay loam, sandy loam, or clay loam, and averages 18 to 35 percent clay, 15 to 40 percent silt, and 30 to 60 percent sand. Reaction is neutral or slightly alkaline.
The Bk horizon has hue of 7.5YR through 2.5Y, value of 5 through 8 dry, 2 through 7 moist, and chroma of 1 through 4. Rock fragment content ranges from 40 to 90 percent. The fine-earth fraction is most commonly sandy loam, but may be fine sandy loam, loam, or sandy clay loam. Content of calcium carbonate equivalent ranges from 15 to 30 percent in the part qualifying as a diagnostic calcic horizon. Many pedons have 5 to 20 percent carbonate concretions on the undersides of rock fragments. Reaction is slightly alkaline or moderately alkaline.
The 2Bk horizon (a C horizon in some pedons) has hue of 7.5YR through 2.5Y. The 2Bk horizon is commonly extremely gravelly sand or extremely gravelly loamy sand, or very gravelly sandy loam. Common textures of C horizons are very gravelly sandy loam and very gravelly sandy clay loam. Reaction is slightly alkaline or moderately alkaline.
COMPETING SERIES: These are the
Cavemountain,
Hoodling,
Latigo (ID),
Maciver (MT),
Nurkey (ID),
Teeler (WY) series.
The Cavemountain soils are moderately deep.
The Hoodling soils have a typic ustic soil moisture regime.
The Latigo and Nurkey soils have a xeric soil moisture regime.
The Maciver and Teeler soils are dry in July and August.
GEOGRAPHIC SETTING: Hodden soils are on outwash terraces, dissected outwash terraces, scarps on pediments, and fan remnants. Slopes range from 1 to 40 percent. The soils formed in alluvium and outwash. Elevation is 8,800 to 10,500 feet. Mean annual precipitation is about 10 to 17 inches. Mean annual temperature is about 35 to 44 degrees F. The frost-free season is about 50 to 85 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gebson and Morset soils. Gebson and Morset soils have less than 35 percent rock fragments throughout.
DRAINAGE AND PERMEABILITY: Well drained; slow to high runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for rangeland. Principal native vegetation is western wheatgrass, Arizona fescue, mountain muhly, prairie junegrass, slimstem muhly, and fringed sagebrush.
DISTRIBUTION AND EXTENT: Intermontane basins of Central Colorado in areas of relatively low precipitation. MLRA 48A, 48B. 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 horizons and features recognized in this pedon are:
Mollic epipedon: from 0 to 10 inches. (A and Bt1 horizons)
Argillic horizon: from 4 to 13 inches. (Bt1 and Bt2 horizons)
Calcic horizon: from 16 to 44 inches. (Bk2 and Bk3 horizons)
Lithologic discontinuity: the contact with extremely gravelly and sandy material (upper boundary of the 2Bk4 horizon).
Series control section: The zone from 0 to 60 inches.
Particle-size control section: The zone from 4 to 13 inches. (entire argillic horizon)