LOCATION ESTELLE AKEstablished Series
TAXONOMIC CLASS: Medial over loamy-skeletal, amorphic over mixed, superactive Andic Haplocryods
TYPICAL PEDON: Estelle silt loam - on a west facing slope of 22 percent at 200 feet elevation under white spruce and paper birch. (all colors are for moist soil)
Oi--0 to 2 inches; brown (7.5YR 4/4) slightly decomposed plant material; very strongly acid (pH 4.6); abrupt smooth boundary. (1 to 4 inches thick)
E--2 to 4 inches; dark grayish brown (10YR 4/2) and brown (10YR 4/3) silt loam; moderate fine granular structure; very friable, nonsticky and nonplastic; many very fine, fine, medium, and coarse roots; strongly acid (pH 5.2); abrupt smooth boundary. (1 to 3 inches thick)
Bs1--4 to 6 inches; yellowish red (5YR 5/6) very fine sandy loam; weak medium granular structure; very friable, nonsticky and nonplastic; common very fine, fine, medium, and coarse roots; moderately acid (pH 5.6); clear smooth boundary. (2 to 6 inches thick)
Bs2--6 to 10 inches; strong brown (7.5YR 5/6) silt loam; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; common very fine, fine, medium, and coarse roots; 2 percent subangular gravel; moderately acid (pH 5.6); gradual wavy boundary. (0 to 6 inches thick)
BC--10 to 18 inches; dark yellowish brown (10YR 4/4) very fine sandy loam; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; few very fine, fine and medium roots; occasional subangular gravel and cobble; moderately acid (pH 5.8); clear irregular boundary. (4 to 14 inches thick)
2C1--18 to 28 inches; brown (10YR 4/3) very gravelly loam; massive; friable, slightly sticky and slightly plastic; 25 percent subangular gravel and 10 percent angular cobble; neutral (pH 6.8); diffuse irregular boundary. (8 to 26 inches thick)
2C2--28 to 60 inches; dark grayish brown (2.5Y 4/2) very gravelly loam; weak thick platy structure, slightly sticky and slightly plastic; 30 percent subangular gravel and 10 percent angular cobble; neutral acid (pH 6.8).
TYPE LOCATION: Matanuska Valley Area, Alaska: about 7 miles west of Knik; about 900 feet N. and 1400 feet E. of the SW corner of section 34, T.16N., R.4W., Seward Meridian.
RANGE IN CHARACTERISTICS: Thickness of the silty loess mantle ranges from 14 to 24 inches and may contain buried horizons. Depth to gravelly glacial till ranges from 14 to 24 inches. The upper part of the control section formed in loess dominated by amorphous material. The lower part of the control section is loamy-skeletal and averages 35 to 65 percent hard rock fragments. Reaction ranges from very strongly acid to moderately acid in the solum and slightly acid to neutral in the substratum. Mean annual soil temperature ranges from 33 to 37 degrees F.
The E, and Eb horizon (where present) has value of 4 or 5 and chroma of 1 to 3. Texture is silt loam or very fine sandy loam.
The Bs, and Bsb horizon (where present) has hue of 2.5YR to 7.5YR, value of 2 to 5, and chroma of 4 to 6. Total carbon is less than 6 percent. Texture is silt loam or very fine sandy loam.
The BC horizon (where present) has hue of 7.5YR or 10YR, value of 3 to 5, and chroma of 3 to 6. Texture is silt loam or very fine sandy loam.
The 2Bs and 2BC horizons (when present) has hue of 7.5YR or 10YR, value of 3 to 5, and chroma of 3 to 6. Texture is loam or sandy loam modified by 10 to 50 percent gravel, 0 to 10 percent cobbles, and 0 to 5 percent stones.
The 2C horizon has hue of 10YR to 2.5Y, value of 3 to 5, and chroma of 2 to 4. Texture is sandy loam or loam, modified by 25 to 65 percent gravel, 0 to 20 percent cobbles, and 0 to 5 percent stones.
COMPETING SERIES: This is the Tokositna series. Tokositna soils have spodic horizon in the upper part of the solum that have 6 to 12 percent total carbon.
GEOGRAPHIC SETTING: The Estelle soils are on glacial till plains and hills. Slopes range from 0 to 85 percent. The soils formed in a loess mantle dominated by amorphous material. The loess mantle is underlain by friable to firm, gravelly glacial till material. Climate is transitional maritime continental. Mean annual temperature is about 35 degrees F. Mean annual precipitation ranges is about 18 inches.
GEOGRAPHICALLY ASSOCIATED SOILS:
DRAINAGE AND PERMEABILITY: Well drained. Medium to very high runoff. Moderate permeability in the loess mantle, moderately slow below.
USE AND VEGETATION: Wildlife habitat, agriculture and urban uses. Native vegetation includes paper birch, white spruce, quaking aspen, bluejoint grass and low shrubs.
DISTRIBUTION AND EXTENT: Purposed MLRA 170A Cook Inlet-Susitna Lowland, Southcentral Alaska. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Matanuska-Susitna Soil Survey Area, Alaska, 1996.
REMARKS: Diagnostic features and horizons recognized in this profile include: an albic horizon from 2 to 4 inches; spodic horizons from 4 to 10 inches; a loess mantle dominated by amorphous material from 2 to 18 inches; loamy-skeletal particle size from 18 to 60 inches; cryic temperature regime.