LOCATION SHAKAN                  AK

Established Series
Rev:WDL/CSC/JPM
02/2022

SHAKAN SERIES

The Shakan series consists of moderately deep, moderately well to well drained soils formed in colluvium on footslopes and backslopes of valley sides. Slopes range from 35 to 150 percent. Mean annual precipitation is about 120 inches, and mean annual temperature is about 45 degrees F.

TAXONOMIC CLASS:

TYPICAL PEDON: Shakan sandy loam - on a NE facing single slope of 150 percent under shrub vegetation at 2000 feet elevation. (All colors are for moist soil)

A1--0 to 3 inches; black (5YR 2.5/2) sandy loam; weak fine granular structure; friable, slightly sticky, slightly plastic; many fine roots; 5 percent gravel; very strongly acid (pH 4.5); clear wavy boundary. (3 to 4 inches thick)

A2--3 to 7 inches; dark reddish brown (10YR 3/3) very gravelly sandy loam; weak fine granular structure; friable, slightly sticky, slightly plastic; few medium, common fine roots; 50 percent gravel; very strongly acid (pH 4.5); gradual wavy boundary. (3 to 4 inches thick)

A3--7 to 17 inches; dark reddish brown (5YR 2.5/2) gravelly sandy loam; weak fine granular structure; friable, slightly sticky, slightly plastic; few medium, common fine roots; 30 percent gravel; very strongly acid (pH 4.5); clear wavy boundary. (7 to 12 inches thick)

C--17 to 25 inches; weak red (2.5YR 4/2) very gravelly sandy loam; massive; friable, slightly sticky, slightly plastic; 50 percent gravel; very strongly acid (pH 4.5); abrupt wavy boundary. (7 to 10 inches thick).

R--25 inches; meta-sedimentary bedrock.

TYPE LOCATION: Ketchikan Area, Alaska; near Anderson Creek in the NW1/4, SE1/4, S3, T73S, R83E, Copper River Meridian.

RANGE IN CHARACTERISTICS: Thickness of the umbric epipedon ranges from 13 to 20 inches. Depth to bedrock ranges from 20 to 40 inches. Base saturation is less than 50 percent. Coarse fragment content ranges from 35 to 60 percent and is dominantly gravel. Reaction ranges from very strongly to medium acid. Mean annual soil temperature ranges from 38 to 42 degrees F. Mean summer soil temperature is about 46 degrees F.

The A horizons have hue from 2.5YR through 10YR; value and chroma moist from 1 through 3. Texture is sandy loam, silt loam, or loam. Coarse fragment content increases with depth and ranges from 5 to 60 percent gravel.

The C horizon has a hue from 2.5YR through 10YR; value moist from 2 through 4; and chroma moist from 1 through 4. Texture is sandy loam, loam or silt loam with more than 35 percent coarse fragments.

COMPETING SERIES: These are the Bigelow, Crannler, Henline, Moohoo, and Walcott series. Bigelow, Moohoo, and Walcott soils are deeper than 40 inches to bedrock. Crannler soils have extremely stony C horizons. Henline soils are slightly acid.

GEOGRAPHIC SETTING: The Shakan soils are on footslopes and backslopes of valley sides and are formed in colluvium. The climate is humid maritime with mean annual precipitation of 120 to 220 inches, much of this which occurs as snow. The mean annual temperature ranges from 43 to 47 degrees F. Slopes range from 35 to 150 percent. Elevation ranges from 1000 to 2000 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hydaburg, McGilvery, St. Nicholas, Sunnyhay, and Tolstoi soils. Hydaburg and Sunnyhay soils are shallow organic alpine soils on ridges and shoulder slopes of mountainsides. The McGilvery are well drained organic soils directly underlain by bedrock on shoulders of mountainsides. The St. Nicholas and Tolstoi soils are shallow to bedrock, have spodic horizons, and occur on backslopes of mountainsides.

DRAINAGE AND PERMEABILITY: Well drained to moderately well drained. Moderately rapid permeability. Rapid runoff.

USE AND VEGETATION: The Shakan soils are used for watershed protection, wildlife habitat, and recreation. The overstory vegetation is dominantly red alder and mountain hemlock regeneration, salmonberry, and blueberry. Understory vegetation is dominantly bunchberry dogwood, deer cabbage, false hellebore, marsh marigold, lady fern and bracken fern.

DISTRIBUTION AND EXTENT: Southeast Alaska. The series is extensive.

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

SERIES ESTABLISHED: Ketchikan Area, Alaska. 1994.

REMARKS: Diagnostic horizons and features recognized in this profile include: an umbric epipedon from 0 to 17 inches based on color and an assumed base saturation of less than 50 percent; the lack of a diagnostic subsoil horizon; loamy-skeletal particle size from 10 to 25 inches; and a cryic temperature regime. The Shakan series formerly classified as thixotropic-skeletal, Humic Cryorthods. The soils, as mapped throughout Southeast Alaska, has no morphological evidence of spodic development. The exchange complex is not dominated by amorphous material.

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National Cooperative Soil Survey
U.S.A.