LOCATION DECEPTION          AK
Established Series
Rev. MHC/JPM/DM
10/2001

DECEPTION SERIES


The Deception series consists of very deep, well drained soils formed in a thin mantle of ash influenced loess overlying friable to firm gravelly glacial till. Deception soils are on glacial till plains, and hills. Slopes range from 0 to 85 percent. The mean annual temperature is about 35 degrees F. and the mean annual precipitation is about 18 inches.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Haplocryods

TYPICAL PEDON: Deception silt loam - on a west facing slope of 37 percent at 150 feet elevation under paper birch and bluejoint grass. (All colors are for moist soil)

Oi--0 to 4 inches; very dusky red (2.5YR 2.5/2) slightly decomposed plant material; very strongly acid (pH 4.5); abrupt smooth boundary. (1 to 5 inches thick)

E--4 to 5 inches; dark grayish brown (10YR 4/2) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; many very fine, fine, medium and coarse roots; strongly acid (pH 5.4); abrupt wavy boundary. (1 to 3 inches thick)

Bs--5 to 9 inches; brown (7.5YR 4/4) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; many very fine, fine, medium and coarse roots; 5 percent subrounded gravel; moderately acid (pH 5.8); clear smooth boundary. (3 to 10 inches thick)

2BC--9 to 21 inches; dark yellowish brown (10YR 4/4) very cobbly sandy loam; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; few very fine and fine roots; 35 percent subrounded gravel, 20 percent subrounded and angular cobble, occasional angular stones; moderately acid (pH 6.0); gradual wavy boundary. (O to 14 inches thick)

2C1--21 to 37 inches; dark grayish brown (2.5Y 4/2) very cobbly sandy loam; massive; firm, slightly sticky and slightly plastic; 35 percent subrounded gravel, 20 percent subrounded and angular cobble, occasional angular stones; neutral (pH 6.6); diffuse wavy boundary.

2C2--37 to 60 inches; dark grayish brown (2.5Y 4/2) very gravelly loam; massive; firm, slightly sticky and slightly plastic; 35 percent subrounded gravel and 10 percent subangular cobble; neutral (pH 6.6). (Combined thickness of the 2C horizons is 43 to 50 inches thick)

TYPE LOCATION: Matanuska Valley Area, Alaska, about 10 miles SW of Knik village; about 1000 feet N. and 900 feet W. of the SE corner of section 28, T.15N., R.4W., Seward Meridian.

RANGE IN CHARACTERISTICS: Thickness of the silty loess mantle ranges from 4 to 10 inches. Depth to gravelly glacial till ranges from 4 to 11 inches. The particle size control section is loamy-skeletal and averages 35 to 60 percent rock fragments. Occasional stones are present throughout. Reaction ranges from very strongly acid to moderately acid in the solum and moderately acid or neutral in the substratum. Mean annual soil temperature is 33 to 37 degrees F.

The E horizon has hue of 1OYR or 2.5Y, value of 4 to 6, and chroma of 1 or 2. Texture is silt loam or very fine sandy loam. Total content of coarse fragments is 0 to 15 percent, 0 to 10 percent gravel and 0 to 5 percent cobbles.

The Bs horizon has hue of 5YR or 7.5YR, value of 3 to 5, and chroma of 4 to 6. Texture is silt loam, loam, very fine sandy loam, or fine sandy loam. Total content of coarse fragments is 0 to 15 percent, O to 5 percent cobble and O to 1O percent gravel.

The 2Bs horizon (where present) has hue of 7.5YR, value of 4, and chroma of 4 to 6. Texture is fine very gravelly sandy loam, gravelly sandy loam, very gravelly sandy loam. Total content of coarse fragments is 15 to 60 percent, 0 to 3 percent stones, 0 to 20 percent cobble, and 10 to 60 percent gravel.

The 2BC horizon has hue of 1OYR or 2.5Y, value of 3 to 5, and chroma of 3 to 6. Texture is fine sandy loam, sandy loam or loam. Coarse fragment content ranges from 5 to 20 percent cobble and 5 to 40 percent gravel. This horizon is absent in many pedons.

The 2C horizons have hue from 1OYR to 5Y, value of 3 to 5, and chroma of 2 to 4. Texture is sandy loam or loam modified by 35 to 60 percent rock fragments. Occasional pockets of extremely gravelly sand are present. Total content of coarse fragments is 35 to 60 percent, 0 to 3 percent stones, 0 to 25 percent cobble and 25 to 60 percent gravel.

COMPETING SERIES: These are the Dinzer, Lastance, Kinklik, Laststance, Mt. Hood, Remedios, and Whetstone series. Dinzer, Lastance, and Mt. Hood soils do not have loess mantles. Kniklik soils contain more than 15 percent coarse fragments in the solum. Remedios soils do not contain volcanic ash. Whetstone soils are moderately deep to bedrock.

GEOGRAPHIC SETTING: The Deception soils are on glacial till plains, and hills. Slopes range from O to 85 percent. The soils formed in a loess mantle consisting of an admixture of amorphous material of volcanic origin and airborne sediments from broad nonvegetated flood plains. The loess mantle is underlain by friable or firm gravelly glacial till material. The climate is transitional maritime - continental. Mean annual temperature is about 35 degrees F. Mean annual precipitation ranges from 14 to 22 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These include Estelle and Kichatna soils. Estelle soils have solums thicker than 10 inches. Kichatna soils have sandy-skeletal substraums.

DRAINAGE AND PERMEABILITY: Well drained. Low to high runoff. Moderate permeability in the loess mantle; moderate or moderately slow in the substratum.

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: Cook Inlet-Susitna Lowlands, Southcentral Alaska. The series is extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Matanuska-Susitna Valley Soil Survey Area, Alaska, 1996.

REMARKS: Diagnostic features and horizons recognized in this profile include: an albic horizon from O to 1 inch; a spodic horizon from 1 to 5 inches, loamy skeletal particle size from 5 to 60 inches; a cryic temperature regime.

This series incorporates part of the range in characteristics of the now inactive Homestead series.


National Cooperative Soil Survey
U.S.A.