LOCATION TERROR LAKE             AK

Established Series
Rev. CAP
06/2025

TERROR LAKE SERIES

Depth class: very deep
Drainage class: somewhat poorly and moderately well drained
Parent material: herbaceous organic material over medial silty volcanic ash over gravelly loamy till
Landscape: Islands
Landform: mountains, hills, and plains in drainageways, swales, and on flood plains
Slopes: 0 to 15 percent
Mean annual precipitation: 900 mm (35 in)
Mean annual temperature: 4 degrees C. (39 degrees F.)
Frost-free season: 20 to 50 days

TAXONOMIC CLASS: Medial over loamy-skeletal, amorphic over mixed, superactive Oxyaquic Haplocryands

TYPICAL PEDON: Terror Lake silt loam - on a grass herbaceous and shrubby till plain at 15 meters (50 feet). (All colors are for moist soil.)

Oe--0 to 8 centimeters (0 to 3 inches); very dark gray (10YR 3/1), dark gray (10YR 4/1), dry; moderately decomposed plant material; soft, very friable, nonsticky, nonplastic; many very fine, fine and common medium and common coarse roots throughout; strongly acid (pH 5.3); clear smooth boundary. (0 to 19 cm, 0 to 7 in thick)

A--8 to 20 centimeters (3 to 8 inches); dark brown (10YR 3/3), brown (10YR 5/3), dry; medial silt loam; weak fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine, common fine, and medium roots throughout; moderately acid (pH 5.8); clear wavy boundary. (8 to 20 cm, 3 to 8 in thick)

Bw1--20 to 58 centimeters (8 to 23 inches); 85 percent brown (10YR 4/3) and 10 percent very dark gray (10YR 3/1) and 5 percent yellowish brown (10YR 5/6) medial silt loam; weak medium subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; common fine, medium, and common coarse roots throughout; moderately acid (pH 5.9); gradual wavy boundary.

Bw2--58 to 98 centimeters (23 to 39 inches); yellowish brown (10YR 5/6) medial silt loam; weak medium subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; common fine and medium roots throughout; 10 percent medium prominent spherical dark gray (10YR 4/1) masses of reduced iron throughout; moderately acid (pH 5.9); abrupt wavy boundary. (Combined thickness is 53 to 85 cm, 21 to 34 in thick)

2C--98 to 200 centimeters (39 to 79 inches); dark grayish brown (2.5Y 4/2) very gravelly sandy loam; massive; slightly hard, friable, slightly sticky, nonplastic; 50 percent gravel and 5 percent cobble; moderately acid (pH 5.7).

TYPE LOCATION: Kodiak Archipelago Soil Survey Area, Alaska; Latitude 57 degrees 12 minutes 48.00 seconds and Longitude 153 degrees 16 minutes 38.00 seconds west, UTM north 6341167.72 and UTM east 483255.85, 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: 0 to 19 cm (0 to 7 in)
Depth to andic properties: 0 to 19 cm (0 to 7 in)
Depth to cambic horizon: 8 to 39 cm (3 to 15 in)
Depth to gravelly till: 61 to 124 cm (24 to 49 in)
Depth to aquic conditions: 41 to 100 cm (16 to 40 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 or their gravelly analogues
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: 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)

2C horizon:
Hue: 7.5YR, 10YR, or 2.5Y
Value: 3 to 6
Chroma: 1 to 4
Texture: loamy sand, loamy coarse sand, sand, or coarse sand and their very or extremely gravelly analogues
Sand: 50 to 85 percent
Clay: 2 to 10 percent
Rock fragments: 35 to 75 percent
Reaction Class: extremely acid to slightly acid (pH 3.5 to 6.5)

Some pedons have sandy-skeletal texture at depths greater than 160 cm (63 in).

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Elevation: 5 to 400 meters (15 to 1325 feet)
Parent material: moderately decomposed herbaceous organic material over medial silty volcanic ash over gravelly loamy till
Landform: mountains, hills, plains, in drainageways and swales and on flood plains
Slope: 0 to 15 percent
Mean annual precipitation: 600 to 2500 mm (24 to 98 in)
Mean annual temperature: 0 to 6 degrees C. (32 to 43 degrees F.)
Frost free period: 20 to 50 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Akalura, Aleneva, Alitak, Koniag, Luchek, Rezanof, Sulua, Tungalara, Wineskey, and Yukuk.
Akalura soils lack aquic conditions within 100cm (40 in), have loamy-skeletal glacial till substratum, and occur on mountains, hills, or ridges on flanks, backslopes, footslopes, and toeslopes.
Aleneva soils have sandy-skeletal glacial till and occur on similar landform positions.
Alitak soils have thick organic horizons, have aquic conditions within 25 cmn (10 in), lack till substratum, and occur in depressions.
Koniag soils lack aquic conditions within 100cm (40 in), have loamy-skeletal glacial till substratum, and occur on plains and hills on higher landform positions.
Luchek soils have thick organic material over loamy-skeletal glacial till and occur on drainageways and depressions.
Rezanof soils have mollic epipedons, lack aquic conditions within 100cm (40 in), and occur on higher landform positions.
Sulua soils have thick organic material over loamy-skeletal glacial till and occur on drainageways and depressions.
Tungalara soils lack aquic conditions within 100cm (40 in) and occur on plains and hills on higher landform positions.
Wineskey soils have loamy glaciofluvial and/or lacustrine substratum and occur in similar landform positions.
Yukuk soils have aquic features within 0 to 25 cm (0 to 10 in) and occur on drainageways and depressions.

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

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

DISTRIBUTION AND EXTENT: MLRA 220 Alexander Archipelago-
Gulf of Alaska Coast.
Extent: moderate.

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 8 cm (0 to 3 in) (moderately decomposed hemic plant material) (Oe horizon)

Andic soil properties: 8 to 98 cm (3 to 39 in) (A, Bw1, Bw2 horizons)

Cambic horizon: 20 to 98 cm (8 to 39 in) (Bw1, Bw2 horizons)

Lithological discontinuity: 98 to 200 cm (39 to 79 in)

Aquic conditions: 41 to 100 cm (16 to 40 in) (Bw1, Bw2, 2C horizons)

ADDITIONAL DATA:

User pedon Id: 10TD 06002

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National Cooperative Soil Survey
U.S.A.