LOCATION DACONT IDEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Calciargidic Argixerolls
TYPICAL PEDON: Dacont gravelly loam, on a 42 percent northwest facing slope at 5,600 feet elevation in rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 3 inches; brown (10YR 5/3) gravelly loam, dark brown (10YR 3/3) moist; moderate very fine and fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine, and few medium roots; many very fine irregular, and few very fine and fine tubular pores; 30 percent gravel; neutral (pH 7.2); clear wavy boundary. (1 to 8 inches thick)
BA--3 to 6 inches; yellowish brown (10YR 5/4) very gravelly loam, dark brown (10YR 3/3) moist; weak very fine and fine subangular blocky structure parting to moderate very fine and fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine and fine, and few medium roots; many very fine irregular, and few very fine and fine tubular pores; 35 percent gravel; slightly alkaline (pH 7.4); clear wavy boundary. (0 to 3 inches thick)
Bt1--6 to 12 inches; yellowish brown (10YR 5/4) very gravelly loam, dark brown (10YR 3/3) moist; weak very fine and fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; common very fine irregular, and common very fine and fine tubular pores; few faint clay films on faces of peds and in pores; 50 percent gravel, 5 percent cobbles; slightly alkaline (pH 7.6); clear wavy boundary.
Bt2--12 to 21 inches; yellowish brown (10YR 5/4) very gravelly loam, brown (10YR 4/3) moist; moderate very fine and fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common very fine and fine, and few medium roots; common very fine irregular, and common very fine and fine tubular pores; few faint clay films on faces of peds and in pores; 50 percent gravel, 5 percent cobbles; slightly alkaline (pH 7.8); gradual wavy boundary.
Bt3--21 to 28 inches; yellowish brown (10YR 5/4) very gravelly loam, brown (10YR 4/3) moist; weak very fine and fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common very fine and fine, and few medium roots; common very fine irregular, and few very fine and fine tubular pores; few faint clay films on faces of peds and in pores; 50 percent gravel, 5 percent cobbles; moderately alkaline (pH 8.0); clear wavy boundary. (combined thickness of Bt horizons is 7 to 24 inches)
2Bk1--28 to 41 inches; brown (7.5YR 5/4) extremely gravelly loam, brown (7.5YR 4/3) moist; weak very fine and fine subangular blocky structure; multicolored pockets vary from 5YR through 10YR; soft, very friable, slightly sticky and slightly plastic; common very fine and few fine and medium roots; common very fine irregular and few very fine and fine tubular pores; 60 percent gravel, 25 percent cobbles; lime coatings on bottoms and some sides of rock fragments; 20 percent soft secondary lime in old root channels; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (13 to 25 inches thick)
2Bk2--41 to 51 inches; brown (7.5YR 5/4) extremely cobbly loam, brown (7.5YR 4/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; multicolored pockets vary from 5YR through 10YR; common very fine roots; many very fine irregular pores; 35 percent gravel, 35 percent cobbles; lime coatings on bottoms of rock fragments; 20 percent soft secondary lime in old root channels; strongly effervescent; moderately alkaline (pH 8.0); gradual wavy boundary.
2Bk3--51 to 60 inches; pale brown (10YR 6/3) extremely cobbly loam, dark brown (10YR 3/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; few very fine roots; many very fine irregular pores; 35 percent gravel, 35 percent cobbles; thin lime layers on bottoms of rock fragments; slightly effervescent; moderately alkaline (pH 7.9).
TYPE LOCATION: Custer County, Idaho; about 2.5 miles west of Ellis, Idaho; about 880 feet west and 60 feet north from the southeast corner of section 28, T.16N., R.20E.
RANGE IN CHARACTERISTICS:
Profile
Average annual soil temperature - 39 to 45 degrees F
Thickness of mollic epipedon - 8 to 16 inches
Depth to calcic horizon - 8 to 35 inches
Particle-size control section:
Clay content - 20 to 32 percent
Rock fragment content - 35 to 60 percent
A horizon:
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3
Bt horizons:
Hue - 5YR through 10YR
Value - 3 through 5 dry, 3 or 4 moist
Chroma - 2 through 4 dry or moist
Texture - very gravelly loam, very cobbly loam, or very gravelly clay loam
2Bk horizons:
Hue - 7.5YR or 10YR
Value - 5 through 8 dry, 3 through 7 moist
Chroma - 2 through 5 dry or moist
Texture - very gravelly loam, extremely gravelly loam,
very cobbly loam, extremely cobbly loam or very gravelly sandy loam
Some pedons have a 2Bkq below 2Bk as few silica coats, 1-2 mm thick on underside of coarse fragments.
COMPETING SERIES: These are the Dacore and Majuba series. Dacore soils are in the pinyon-juniper vegetative zone and the soils receive summer precipitation in July to October. Majuba soils are moderately deep to bedrock.
GEOGRAPHIC SETTING: These soils are on mountainsides, foothills, and fan terraces and have slopes of 4 to 70 percent. These soils formed in colluvium from extrusive igneous rocks. The average annual temperature is 37 to 43 degrees F. and the average annual precipitation is 11 to 13 inches. The frost-free period is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dawtonia, Ezbin, Gaciba, Howcan, Hagenbarth, and Venum series. Dawtonia soils lack a mollic epipedon. Ezbin soils are on mountains and have a cryic temperature regime and lack carbonates in the profile. Gaciba soils are on mountains and have bedrock at a depth of 10 to 20 inches. Hagenbarth soils are on mountainsides and have less than 35 percent rock fragments throughout the profile and have a cryic temperature regime. Howcan soils are on mountainsides, foothills, and fan terraces and lack a calcic horizon. Venum soils are on mountains, ridges, and foothills and lack a mollic epipedon and have an aridic moisture regime.
DRAINAGE AND PERMEABILITY: Well drained; permeability is moderate in the upper part and very rapid in the lower part.
USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. Native vegetation is Wyoming big sagebrush, bluebunch wheatgrass, western wheatgrass, and Salmon wildrye.
DISTRIBUTION AND EXTENT: Southcentral Idaho; MLRA 12. They are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Custer County, Idaho, 1999
REMARKS: Diagnostic features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 12 inches (A, BA, and Bt1 horizons)
Argillic horizon - The zone from 6 to 28 inches (Bt1, Bt2, and Bt3 horizons)
Calcic horizon - The zone from 28 to 60 inches (Bk1, Bk2, and Bk3 horizons)
Particle-size control section - The zone from 6 to 26 inches (Bt1, Bt2, and part of Bt3 horizons)
Aridic moisture regime