LOCATION AKALURA AK

Tentative Series
Rev. CAP
05/2024

AKALURA SERIES

Depth class: Very deep
Drainage class: Well drained
Parent material: herbaceous organic material over sandy and loamy volcanic ash over medial silty volcanic ash over gravelly loamy till
Landscape: Islands
Landform: mountain, hills, and ridges
Slopes: 15 to 50 percent
Mean annual precipitation: about 2250 mm (88.5 in)
Mean annual temperature: about 2 degrees C. (34 F.)

TAXONOMIC CLASS: Medial, amorphic Typic Haplocryands

TYPICAL PEDON: Akalura ashy loamy sand - on a grass herbaceous mountain flank at elevation of 356 meters (1176 feet). (All colors are for moist soil)

Oe--0 to 4 centimeters (0 to 2 inches); very dark brown (7.5YR 2.5/2), dark brown (7.5YR 3/2), dry; moderately decomposed plant material; very friable, soft, nonsticky, nonplastic; many very fine, common fine and medium, and few coarse roots throughout; strongly acid (pH 5.3); abrupt smooth boundary. (1 to 15 cm, 1 to 6 in thick)

C--4 to 24 centimeters (2 to 9 inches); 50 percent pale brown (10YR 6/3) and 50 percent strong brown (7.5YR 5/6), very pale brown (10YR 7/4), dry; ashy loamy sand; single grain; loose, nonsticky, nonplastic; many very fine, common fine and medium roots throughout; strongly acid (pH 5.2); abrupt smooth boundary. (3 to 23 cm, 1 to 9 in thick)

2A--24 to 30 centimeters (9 to 12 inches); medial silt loam; weak medium subangular blocky structure; very friable, soft, nonsticky, nonplastic; common very fine, fine, and medium roots throughout; 5 percent gravel; very strongly acid (pH 5.0); clear smooth boundary. (2 to 13 cm, 1 to 5 in thick)

2Bw1--30 to 55 centimeters (12 to 22 inches); medial silt loam; moderate medium subangular blocky structure; friable, slightly hard, nonsticky, nonplastic; common very fine, fine, and medium roots throughout; 5 percent gravel; very strongly acid (pH 4.9); clear smooth boundary.

2Bw2--55 to 65 centimeters (22 to 26 inches); dark brown (7.5YR 3/4) medial silt loam; moderate medium subangular blocky structure; friable, slightly hard, nonsticky, nonplastic; common very fine roots throughout; 10 percent gravel; very strongly acid, pH 4.9; clear smooth boundary.

2Bw3--65 to 120 centimeters (26 to 47 inches); medial silt loam; moderate medium subangular blocky structure; friable, slightly hard, nonsticky, nonplastic; 10 percent gravel; strongly acid (pH 5.1); clear smooth boundary. (Combined thickness is 45 to 105 cm, 18 to 42 in thick)

3C--120 to 200 centimeters (47 to 79 inches); dark grayish brown (2.5Y 4/2) very gravelly sandy loam; massive; friable, slightly hard, slightly sticky, slightly plastic; 50 percent gravel and 5 percent cobble; very strongly acid (pH 4.9).

TYPE LOCATION: Kodiak Archipelago Soil Survey Area, Alaska; Latitude 58 degrees 8 minutes 37.75 seconds and Longitude 153 degrees 2 minutes 38.01 seconds west, UTM north 6444723.11 and UTM east 497416.01, zone 5, Datum WGS84.

RANGE IN CHARACTERISTICS:

Soil moisture regime: udic
Mean annual soil temperature: 1.6 to 3.3 degrees C. (34.8 to 37.9 degrees F.)
Thickness of organic material: 1 to 15 cm (1 to 6 in)
Thickness of 1912 ash: 3 to 23 cm (1 to 9 in)
Depth to andic properties: 4 to 38 cm (2 to 15 in)
Depth to cambic horizon: 6 to 51 cm (3 to 20 in)
Depth to gravelly till: 51 to 156 cm (20 to 61 in)

Oa, Oe, Oi horizon:
Hue: 7.5YR to 10YR
Value: 2 to 5
Chroma: 1 to 4
Texture: slightly, moderately, or highly decomposed plant material
Organic matter: 60 to 90 percent
Reaction class: extremely acid to moderately acid (pH 3.5 to 6.0)

C horizon:
Hue: 7.5YR to 10YR
Value: 2 to 5
Chroma: 1 to 4
Texture: (ashy and glassy) sand, loamy sand, loamy fine sand, very fine sandy loam, sandy loam, or silt loam
Sand: 30 to 90 percent
Clay: 2 to 8 percent
Silt: 10 to 55 percent
Reaction class: extremely acid to moderately acid (pH 3.5 to 6.0)

2A horizon:
Hue: 7.5YR to 10YR
Value: 2 to 5
Chroma: 1 to 3
Texture: medial silt loam, silt, loam, and very fine sandy loam or their gravelly analogues
Rock fragments: 0 to 30 percent
Silt: 40 to 90 percent
Clay: 2 to 10 percent
Reaction class: extremely acid to moderately acid (pH 3.5 to 6.0)

2Bw horizon:
Hue: 7.5YR to 10YR
Value: 2 to 5
Chroma: 3 to 6
Texture: (medial) silt loam, silt, loam, or very fine sandy loam, or their gravelly analogues
Silt: 40 to 90 percent
Clay: 2 to 12 percent
Rock fragments: 0 to 30 percent
Reaction class: extremely acid to moderately acid (pH 3.5 to 6.0)

3C horizon:
Hue: 7.5YR, 10YR, or 2.5Y
Value: 3 to 6
Chroma: 1 to 4
Texture: sandy loam, fine sandy loam, coarse sandy loam, loamy sand, loamy coarse sand, or their very or extremely gravelly analogues
Sand: 50 to 85 percent
Clay: 2 to 10 percent
Rock fragments: 35 to 80 percent
Reaction Class: extremely acid to slightly acid (pH 3.5 to 6.5)

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Elevation: 350 to 900 meters (1100 to 3000 feet)
Parent material: moderately decomposed herbaceous organic material over sandy and loamy volcanic ash over medial silty volcanic ash over gravelly loamy till
Landform: mountains, hills, and ridges on flanks, back slopes or toeslopes
Slope: 15 to 60 percent
Mean annual temperature: 0 to 4 degrees C. (32 to 39 degrees F.)
Mean annual precipitation: 1500 to 3000 mm (59 to 118 in)
Frost free period: 20 to 50 days

GEOGRAPHIC SETTING:
Depth class: very deep
Drainage class: well drained
Parent material: volcanic ash over gravelly glacial till or colluvium
Landform: mountain, hills, and ridges
Slopes: 3 to 75 percent
Mean annual precipitation: 900 to 2000 mm (35 to 79 in)
Mean annual temperature: 0 to 4 degrees C. (32 to 39 degrees F.)
Frost-free season: 20 to 50 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Ayakulik, Bidarka, Kaguyak, Kodiak, Luchek, Shuyak, Spiridon, Sulua, Terror Lake, Tonki, and Tungalara.
Ayakulik soils have bedrock at depths less than 100 cm (40 in), lack glacial till substratum, and occur on mountain tops and flanks, and hill or ridge summits, shoulders, and backslopes.
Bidarka soils have bedrock at depths less than 100 cm (40 in), lack glacial till substratum, have skeletal particle-sized control sections, and occur on mountain tops and flanks, and hill or ridge summits, shoulders, and backslopes.
Kaguyak soils have bedrock at depths less than 50 cm (20 in), lack glacial till substratum, have skeletal particle-sized control sections, and occur on mountain tops and flanks, and hill or ridge summits, shoulders, and backslopes.
Kodiak soils have spodic horizons and occur on similar landform positions.
Luchek soils have thick organic material over skeletal glacial till and occur on drainageways and depressions on lower sloping mountain flanks and hill or ridge backslopes and toeslopes.
Shuyak soils have bedrock at depths less than 50 cm (20 in), lack glacial till substratum, and occur on mountain tops and flanks, and hill or ridge summits, shoulders, and backslopes.
Spiridon soils have bedrock at depths less than 100 cm (40 in) and occur on mountain tops and flanks, and hill or ridge summits, shoulders, and backslopes.
Sulua soils have thick organic material over skeletal glacial till and occur on drainageways and depressions on lower sloping mountain flanks and hill or ridge backslopes and toeslopes.
Terror Lake soils have aquic features within 41 to 100 cm (16 to 40 in) and occur on drainageways and depressions on lower sloping mountain flanks and hill or ridge backslopes and toeslopes.
Tonki soils have aquic features within 0 to 25 cm (0 to 10 in) and occur on drainageways and depressions on lower sloping mountain flanks and hill or ridge backslopes and toeslopes.
Tungalara soils have skeletal particle-sized control sections and occur on similar positions.

DRAINAGE AND PERMEABILITY:
Drainage class: well drained
Saturated Hydraulic Conductivity: moderately high to very high in the C horizon, moderately high to high in the 2A and 2Bw horizons, and high in the 3C.
Permeability: moderate to very rapid in the C horizon and moderate to rapid in the 2A, 2Bw, and 3C horizons.
Runoff: medium to very high.

USE AND VEGETATION:
Used for water shed. Native vegetation is Sitka Spruce, Forb meadow and Grass.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Wasilla, Alaska

DISTRIBUTION AND EXTENT: MLRA 225 Southern Alaska Peninsula Mountains
Extent: moderate.

SERIES ESTABLISHED: Kodiak Archipelago Soil Survey, Alaska, 2024.

REMARKS: Diagnostic features and horizons recognized in this profile include:

Organic material: 0 to 4 cm (0 to 2 in) (moderately decomposed hemic plant material) (Oe horizon)

1912 volcanic glass (ashy) material: 4 to 24 cm (2 to 9 in) (C horizon)

Andic soil properties: 24 to 120 cm (9 to 57 in) (2A, 2Bw1, 2Bw2, and 2Bw3 horizons)

Cambic horizon: 30 to 120 cm (12 to 47 in) (2Bw1, 2Bw2, and 2Bw3 horizons)

Lithological discontinuity: 120 to 200 cm (47 to 79 in)

Source of the volcanic ash is the 1912 eruption of Mt. Novarupta and Mt. Katmai on the Alaska Peninsula.

ADDITIONAL DATA:

User pedon Id: 08SS 05106

National Cooperative Soil Survey
U.S.A.