LOCATION AYAKULIK AK

Established Series
Rev. CAP
06/2025

AYAKULIK SERIES

Depth class: moderately deep
Drainage class: well drained
Parent material: herbaceous organic material over medial silty volcanic ash over residuum weathered from graywacke
Landscape: Islands
Landform: mountains, hills, and ridges
Slopes: 3 to 70 percent
Mean annual precipitation: about 1300 mm (51 in)
Mean annual temperature: about 0 degrees C. (32 degrees F.)

TAXONOMIC CLASS: Medial, ferrihydritic Andic Humicryods

TYPICAL PEDON: Ayakulik - on a grass herbaceous mountain flank at elevation of 195 meters (645 feet) elevation. (All colors are for moist soil)

Oa--0 to 3 centimeters (0 to 1 inches); very dark brown (7.5YR 2.5/2), brown (7.5YR 4/2), dry; highly decomposed plant material; soft, very friable, nonsticky, nonplastic; many very fine, fine, and common medium roots throughout; very strongly acid (pH 4.5); clear smooth boundary. (0 to 10 cm, 0 to 4 in thick)

A1--3 to 10 centimeters (1 to 4 inches); dark brown (7.5YR 3/2), brown (7.5YR 4/2), dry; medial silt loam; weak fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine, fine, and common medium roots throughout; very strongly acid (pH 4.7); gradual smooth boundary.

A2--10 to 17 centimeters (4 to 7 inches); very dark brown (7.5YR 2.5/3) medial silt loam; weak fine granular structure; soft, very friable, nonsticky, nonplastic; common very fine, fine, and medium roots throughout; strongly acid (pH 5.3); clear wavy boundary. (Combined thickness is 5 to 18 cm, 2 to 7 in thick)

Bw1--17 to 40 centimeters (7 to 16 inches); 90 percent yellowish brown (10YR 5/4) and 10 percent dark brown (10YR 3/3) medial silt loam; weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine and fine roots throughout; slightly acid (pH 6.1); gradual smooth boundary.

Bw2--40 to 70 centimeters (16 to 28 inches); brown (7.5YR 5/4) medial silt loam; weak medium angular blocky structure; slightly hard, friable, nonsticky, nonplastic; common very fine and fine roots throughout; slightly acid (pH 6.1); clear wavy boundary.

Bw3--70 to 78 centimeters (28 to 31 inches); brown (7.5YR 4/4) medial silt loam; weak fine angular blocky structure; slightly hard, friable, nonsticky, nonplastic; slightly acid (); abrupt irregular boundary. (Combined thickness is 38 to 82 cm, 15 to 32 in thick)

2R--78 to 103 centimeters (31 to 41 inches); strongly to indurated graywacke bedrock.

TYPE LOCATION: Kodiak Archipelago Soil Survey Area, Alaska; Latitude 57 degrees 2 minutes 54.00 seconds and Longitude 153 degrees 15 minutes 45.00 seconds west, UTM north 6322796.86 and UTM east 484074.38, zone 5, Datum WGS84.

RANGE IN CHARACTERISTICS:

Soil moisture regime: Udic
Mean annual soil temperature: -2 to 4 degrees C (28 to 39 degrees F.)
Thickness of organic material: 0 to 10 cm (0 to 4 in)
Depth to andic properties: 0 to 10 cm (0 to 4 in)
Depth to cambic horizon: 5 to 28 cm (2 to 11 in)
Depth to bedrock: 43 to 110 cm (16 to 43 in)

Oa, Oe, Oi horizon:
Hue: 7.5YR to 10 YR
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)

A horizon:
Hue: 7.5YR to 10 YR
Value: 2 to 5
Chroma: 1 to 3
Texture: medial silt loam, silt, loam, and very fine sandy loam
Rock fragments: 0 to 25 percent
Silt: 40 to 90 percent
Clay: 2 to 10 percent
Reaction class: extremely acid to moderately acid (pH 3.5 to 6.0)

Bw horizon:
Hue: 5YR, 7.5YR, or 10YR
Value: 2 or 3
Chroma: 1 to 4
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)

3R horizon: Strongly to indurated bedrock.

COMPETING SERIES: These are the Cruiser (OR), Keel (OR), Longbow (OR), Molawa (OR), Oneonta (OR), and Soosap (OR) series.
Cruiser soils lack a lithic contact, have mean annual temperature greater than 4 degrees C. (39 degrees F.), have mean annual precipitation greater than 3000 m (98 in), have frost free periods greater than 50 days, and occur on similar landform positions.
Keel soils have igneous bedrocks, lack medial andic properties, have mean annual temperature greater than 4 degrees C. (39 degrees F.), have frost free periods greater than 50 days, and occur on similar landform positions.
Longbow soils lack lithic contact within 100 cm (40 in), have mean annual air temperature greater than 4 degrees C. (39 degrees F.), have frost free periods greater than 50 days, and occur on structural benches and cirque floors.
Molawa soils lack lithic contact within 100 cm (40 in), have mean annual air temperature greater than 4 degrees C. (39 degrees F.), and occur on mountains, volcanic cones, and ridges.
Oneonta soils lack lithic contact within 100 cm (40 in), have mean annual air temperature greater than 4 degrees C. (39 degrees F.), have frost free periods greater than 50 days, and occur on similar landform positions.
Soosap soils have tuff, breccias, or andesite bedrock, have mean annual air temperature greater than 4 degrees C. (39 degrees F.), have frost free periods greater than 50 days, and occur on similar landform positions.

GEOGRAPHIC SETTING:
Elevation: 150 to 1210 meters (495 to 4000 feet)
Parent material: herbaceous organic material over medial silty volcanic ash over residuum weathered from graywacke
Landform: mountains, hills and ridges
Slopes: 3 to 70 percent
Mean annual precipitation: 900 to 2000 mm (35 to 79 in)
Mean annual temperature: -2 to 4 degrees C. (28 to 39 degrees F.)
Frost free period: 20 to 50 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Akalura, Bidarka, Kaguyak, Kodiak, Luchek, Shuyak, Spiridon, Sulua, Terror Lake, Tonki, and Tungalara.
Akalura soils lack bedrock at depths less than 100 cm (40 in), have glacial till substratum, and occur on mountain flanks, and hill or ridge backslopes, footslopes, and toeslopes.
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: very high in the Oa horizon, moderately high to high in the A, Bw1, Bw2, Bw3 horizons, and very low to low in the 2R.
Permeability: rapid to very rapid in the Oa horizon, moderate to rapid in the A, Bw1, Bw2, Bw3 horizons, and impermeable to very slow in the 2R.
Runoff: high to very high.

USE AND VEGETATION:
Used for wildlife. Native vegetation is Sitka Spruce with Devils club understory.

DISTRIBUTION AND EXTENT: MLRA 220 Alexander Archipelago-
Gulf of Alaska Coast and MLRA 225 Southern Alaska Peninsula Mountains.
Extent: extensive.

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

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

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

Organic material: 0 to 3 cm (0 to 1 in) (highly decomposed hemic plant material) (Oa horizon)

Andic soil properties: 3 to 78 cm (1 to 31 in) (A1, A2, Bw1, Bw2, Bw3 horizons)

Cambic horizon: 17 to 78 cm (7 to 31 in) (Bw1, Bw2, Bw3 horizons)

Lithic contact: 78 to 103 cm (31 to 43) (3R horizon)

ADDITIONAL DATA:

User pedon Id: 10MM 06201

National Cooperative Soil Survey
U.S.A.