LOCATION CLUFF UTEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic Mollic Haplocryalfs
TYPICAL PEDON: Cluff loam on a 15 percent convex east-facing slope in forest land. (Colors are for moist soil unless otherwise stated.)
A1--0 to 4 inches; dark brown (7.5YR 3/2) loam, dark grayish brown (10YR 4/2) dry; strong very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine, fine and common medium roots; few very fine vesicular pores; 10 percent gravel; slightly acid (pH 6.5); clear smooth boundary. (1 to 6 inches thick)
A2--4 to 9 inches; dark brown (7.5YR 3/2) gravelly loam, brown (10YR 5/3) dry; weak medium subangular blocky structure parting to moderate medium granular; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, fine and common medium roots; few very fine tubular pores; 15 percent gravel, 5 percent cobbles; slightly acid (pH 6.5); clear smooth boundary. (0 to 8 inches thick)
E--9 to 16 inches; brown (10YR 4/3) very gravelly loam, light brown (7.5YR 6/4) dry; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, fine and common medium roots; few very fine tubular pores; 25 percent gravel, 10 percent cobbles; slightly acid (pH 6.5); clear smooth boundary. (4 to 15 inches thick)
B/E--16 to 20 inches; 70 percent B part is strong brown (7.5YR 4/6) very cobbly clay loam, brown (7.5YR 5/4) dry, weak fine and medium subangular blocky structure, hard, friable, moderately sticky and moderately plastic, few faint clay films on faces of peds; 30 percent E part is brown (10YR 4/3) very cobbly very fine sandy loam, light brown (7.5YR 6/4) dry; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic. Both Bt and E have common very fine and fine roots; many very fine tubular pores; 20 percent gravel, 15 percent cobbles, 10 percent stones; slightly acid (pH 6.5); clear wavy boundary. (0 to 10 inches thick)
Bt1--20 to 33 inches; yellowish red (5YR 4/6) very cobbly clay, yellowish red (5YR 5/6) dry; moderate medium and fine subangular blocky structure; extremely hard, very firm, moderately sticky and moderately plastic; few very fine and fine roots; many fine tubular pores; many faint clay films on faces of peds; 25 percent gravel, 20 percent cobbles, 5 percent stones; slightly acid (pH 6.2); gradual wavy boundary. (7 to 15 inches thick)
Bt2--33 to 54 inches; yellowish red (5YR 4/6) very cobbly clay, reddish yellow (5YR 6/6) dry; weak coarse and medium subangular blocky structure; extremely hard, very firm, moderately sticky and moderately plastic; few very fine and fine roots; few fine tubular pores; common faint clay films on faces of peds; 20 percent gravel, 20 percent cobbles, 10 percent stones; slightly acid (pH 6.2), abrupt smooth boundary (7 to 20 inches thick)
R--54 inches; conglomerate.
TYPE LOCATION: Summit County, Utah; about 1/4 mile west of Porcupine Reservoir, about 2,250 feet west and 1,400 feet south of northeast corner, sec. 21, T. 3 N., R. 7 E.
RANGE IN CHARACTERISTICS: Depth to a lithic contact is 40 to 60 inches. The particle-size control section averages 35 to 50 percent clay. The mean annual soil temperature is 37 to 42 degrees F., and the mean summer soil temperature at 20 inches is 46 to 53 degrees F. The soil moisture regime is udic.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3 moist, 4 or 5 dry, and chroma is 2 or 3. Texture is loam or gravelly loam. Reaction is moderately to slightly acid. Rock fragment content is 10 to 25 percent.
The E horizon has hue of 7.5YR or 10YR, value of 3 or 4 moist, 5 or 6 dry, and chroma is 3 or 4 moist and 2 to 4 dry. Clay content is 18 to 27 percent. Rock fragment content is 20 to 50 percent. Reaction is slightly acid to strongly acid.
The Bt horizon has hue of 5YR to 7.5YR, value of 3 or 4 moist, 4 to 6 dry and chroma of 4 to 6. Texture is very gravelly clay, very cobbly clay, very cobbly clay loam or extremely cobbly sandy clay. Rock fragment content commonly increases with depth and ranges from 35 to 80 percent. Reaction is slightly acid to moderately acid.
COMPETING SERIES: These are the
Cochedome (T CO),
Mudbuz (T CO),
Reck (T ID),
Recklor (UT),
Winz (NV) and
Yence (UT) series.
Cochedome soils are 20 to 40 inches to bedrock.
Mudbuz soils are more than 60 inches to bedrock and lack E horizons.
Reck soils are more than 60 inches to bedrock and are neutral to moderately alkaline.
Recklor soils are more than 60 inches to bedrock and lack E horizons.
Winz soils have less than 18 percent clay in the E horizon.
Yence soils lack and E horizon and have hue of 10R to 5YR in the Bt horizon.
GEOGRAPHIC SETTING: Cluff soils are on moderately sloping to very steep mountain slopes. Slopes range from 8 to 60 percent. These soil formed in residuum and colluvium derived from quartzite, limestone, conglomerate and sandstone. The average annual precipitation ranges from 22 to 35 inches. The mean annual temperature is 36 to 42 degrees F, and the mean summer temperature is 55 to 58 degrees F. The mean average freeze-free period is 20 to 60 days. Elevation ranges from 6,800 to 10,600 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Agassiz, Baird Hollow, Daybell, Scout and Session soils. Agassiz, Baird Hollow, Daybell and Sessions soils have mollic epipedons. Also, Agassiz soils are 20 inches or less to bedrock and lack albic and argillic horizons. Scout soils lack argillic horizons and have a very gravelly sandy loam particle size control section. Sessions soils lack albic horizons and have less than 35 percent rock fragments in the argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; slow permeability.
USE AND VEGETATION: Cluff soils are used for watershed, timber production, and limited grazing by livestock and wildlife. The potential vegetation is alpine fir, Douglas fir, aspen and an understory chokecherry, buck brush, meadowrue and dryland sedge.
DISTRIBUTION AND EXTENT: High mountain areas of central and northern Utah. This soil is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Wasatch County, (Heber Valley Soil Survey Area) Utah, 1971.
REMARKS: Diagnostic horizons and features recognized in the pedon are:
Ochric epipedon - the zone from the surface to 9 inches. This horizon does not qualify for a mollic epipedon because it is too thin. (A1, A2 horizons)
Argillic horizon: the zone from 16 to 54 inches (B/E, Bt1, Bt2 horizons).
Particle-size control section: The zone from 16 to 36 inches (B/E, Bt1, and part of Bt2 horizon)
The type location was moved from Wasatch County to Summit County, Utah to better represent the mapping.
Classification: Keys to Soil Taxonomy, Eighth Edition, 1998.
ADDITIONAL DATA: