LOCATION STRANDLINE              AK

Established Series
Rev. KMO-JPM
02/2022

STRANDLINE SERIES

The Strandline series consists of very deep, well drained soils formed in a mantle of ash-influenced loess overlying firm glacial till. Strandline soils are on moraines and mountain footslopes. Slopes range from 0 to 45 percent. Mean annual temperature is about 34 degrees F., and the average annual precipitation is about 26 inches.

TAXONOMIC CLASS: Medial over loamy, mixed, superactive Andic Haplocryods

TYPICAL PEDON: Strandline silt loam - on a southwest facing slope of about 5 percent under forest vegetation. (All colors are for moist soil)

Oe--2 inches to 0; mat of roots and moderately decomposed forest litter; abrupt smooth boundary. (1 to 4 inches thick)

A--0 to 2 inches; dark reddish brown (5YR 3/2) silt loam; weak fine granular structure; very friable; nonsticky and nonplastic; many fine and medium roots; very strongly acid; abrupt smooth boundary. (0 to 3 inches thick)

E--2 to 5 inches; gray (10YR 5/1) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; many fine and medium roots; very strongly acid; abrupt smooth boundary. (1 to 4 inches thick)

Bhs--5 to 8 inches; dark reddish brown (5YR 3/4) silt loam; weak fine subangular blocky structure; very friable, smeary, nonsticky and nonplastic; common fine and few medium roots; very strongly acid; abrupt smooth boundary.

Bs1--8 to 15 inches; dark brown (7.5YR 4/4) silt loam; weak fine subangular blocky structure; very friable, smeary, nonsticky and nonplastic; few fine and medium distinct yellowish brown (10YR 4/4) and strong brown (7.5YR 5/6) stains along root channels; few fine and medium roots; very strongly acid; clear wavy boundary.

Bs2--15 to 18 inches; dark yellowish brown (10YR 4/4) silt loam; weak fine subangular blocky structure; very friable, slightly smeary, nonsticky and nonplastic; few fine distinct strong brown (7.5YR 5/6) stains along root channels; few fine roots; very strongly acid; clear smooth boundary.

Bs3--18 to 20 inches; brownish yellow (10YR 6/6) silt loam; weak fine subangular blocky structure; very friable, slightly smeary; nonsticky and nonplastic; few fine distinct strong brown (7.5YR 5/6) and light brown (7.5YR 6/4) stains along root channels; very strongly acid; clear smooth boundary. (Combined B horizons: 7 to 15 inches thick)

Eb--20 to 22 inches; gray (5Y 5/1) silt loam; weak fine subangular blocky structure; very friable, nonsticky and nonplastic; common medium distinct patches of strong brown (7.5YR 4/6); very strongly acid; abrupt smooth boundary. (1 to 3 inches thick)

Bsb--22 to 26 inches; dark yellowish brown (10YR 4/4) silt loam; weak fine subangular blocky structure; very friable, nonsticky and nonplastic; strongly acid; gradual wavy boundary.

BCb--26 to 31 inches; dark grayish brown (2.5Y 4/2) silt loam; weak fine subangular blocky structure; very friable, nonsticky and nonplastic; strongly acid; clear wavy boundary. (Combined Bb horizons: 2 to 12 inches thick)

2C--31 to 60 inches; olive gray (5Y 5/2) gravelly silt loam; massive; firm; 15 percent gravel and 5 percent cobbles; strongly acid.

TYPE LOCATION: Yentna Area, Alaska; in the SW 1/4 of the NW 1/4 of section 17, T.22N., R.10W., Seward Meridian.

RANGE IN CHARACTERISTICS: The pedons have a bisequal sola. The combined sola ranges from 14 to 30 inches. The upper 4 inches of the spodic horizons have less than 6 percent organic carbon. The loess mantle ranges from 20 to 37 inches in thickness over the firm, glacial till substratum. The exchange complex of the sola is dominated by amorphous material. Reaction throughout the profile ranges from extremely acid to strongly acid.

The A horizon, when present, has hue from 5YR to 10YR; value moist of 2 or 3 and chroma moist of 1 or 2.

The E horizon has hue from 5YR to 10YR; value moist from 4 to 6; and chroma moist of 1 or 2. Texture is silt loam or very fine sandy loam.

The Bhs horizon has hue from 2.5YR to 10YR; value moist of 2 or 3; and chroma moist from 1 to 4.

The Bs horizons have hue from 2.5YR to 10YR; value moist from 4 to 6; and chroma moist from 3 to 6. Texture is silt loam or very fine sandy loam.

The buried solum is similar in color and texture to the surface solum.

C horizons are present below the buried solum in some pedons.

The 2C horizon is massive, firm, loam or silt loam. Coarse fragment content ranges from 5 to 35 percent with 5 to 30 percent gravel and 0 to 5 percent cobble.

COMPETING SERIES: These are the Boulder Point, Cohoe, Darling, Flat Horn, Kenai, Kroto, Swanson(T), Tuomi(T), and Whitsol series of the same family, and the Chulitna, Kashwitna, Nancy, Puntilla, and Chuit series. Boulder Point, Darling, Flat Horn, Tuomi(T), and Whitsol soils have loose or friable substratums. Cohoe soils have stratas of sand and sandy loam in the control section. Kenai soils have greater than 18 percent clay in the substratum. Swanson soils are not bisequal. Kroto soils have loess mantles thinner than 20 inches overlying glacial till. Chuit and Puntilla soils have more than 6 percent organic carbon in the upper part of the spodic horizon. Chulitna, Kashwitna, and Nancy soils are sandy or sandy-skeletal in the lower part of the control section.

GEOGRAPHIC SETTING: Strandline soils are on moraines and mountain footslopes that have been subject to glacial depostion. The soils formed in a mantle of loess overlying massive, firm, glacial till. The loess mantle contains varying amounts of volcanic ash. Slope ranges from 0 to 45 percent. The average annual precipitation ranges from 20 to 34 inches. The mean annual temperature ranges from 32 to 36 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Kroto and Puntilla soils, and the Spenard soils. Spenard soils are in depressional areas and are poorly drained.

DRAINAGE AND PERMEABILITY: Well drained. Slow to rapid runoff. Moderate permeability in the loess mantle and moderately slow in the till substratum.

USE AND VEGETATION: The soils are mostly forested. The dominant trees are paper birch and white spruce. The understory consists of bluejoint grass, alder, and forbs.

DISTRIBUTION AND EXTENT: South-central, Alaska. The soil is extensive.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA

SERIES ESTABLISHED: Yentna Area, Alaska, 1986.

REMARKS: Diagnostic horizons and features that occur in this pedon include: spodic horizons from 5 to 15 inches; a cryic temperature regime; amorphous material dominant in the control section from 0 to 31 inches; loamy particle size class from 31 to 60 inches.

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National Cooperative Soil Survey
U.S.A.