LOCATION TOWNLAKE                AK

Established Series
SDB/MJS
08/2025

TOWNLAKE SERIES

Depth class: very deep, deep to permafrost
Drainage class: moderately well drained
Parent material: organic material over silty loess over organic material over silty loess
Landscape: uplands, hills, foothills, mountains and river valleys
Landform: hills, hillslopes, river valleys, mountain slopes and hillslopes
Slope: 0 to 20 percent
Mean annual precipitation: about 350 mm (14 in)
Mean annual air temperature: about -1 degrees C (30 F)
Frost-free period: 32 to 103 days

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, nonacid, subgelic Folistic Molliturbels

TYPICAL PEDON: Townlake moderately decomposed plant material in a black spruce community on a southeastern facing convex, linear footslope with a slope of 7 percent and an elevation of 609m (2000 ft).

Oi--0 to 12 cm (0 to 5 in); slightly decomposed plant material, weak red (7.5R 4/2) dry, very dark brown (7.5YR 2.5/2) broken face moist; many very fine, fine, and common medium roots throughout; neutral (pH 6.6); clear wavy boundary (10 to 13 cm, 4 to 5 in)

Oe--12 to 25 cm (5 to 10 in); moderately decomposed plant material, very dark brown (7.5YR 2.5/2) broken face moist; many very fine, few fine, common medium, and many coarse roots throughout; neutral (pH 6.6); clear wavy boundary (10 to 14 cm, 4 to 6 in)

Oa--25 to 37 cm (10 to 15 in); highly decomposed plant material, black (10YR 2/1) broken face, moist; many very fine, fine, and medium roots throughout; neutral (pH 6.6); gradual wavy boundary (5 to 12 cm, 2 to 5 in)

A/Oajj1--37 to 66 cm (15 to 26 in); silt loam, very dark brown (10YR 2/2) broken face moist; moderate coarse subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; nonsmeary; common very fine and fine roots throughout; very fine and fine dendritic tubular pores; neutral (pH 6.8); gradual wavy boundary. (10 to 35 cm, 4 to 14 in)

A/Oajj2--66 to 78 cm (26 to 31 in); silt loam, very dark gray (10YR 3/1) broken face moist; weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; nonsmeary; common very fine and fine roots throughout; very fine dendritic tubular pores; neutral (pH 6.8); abrupt wavy boundary (8 to 15 cm, 3 to 6 in)

Oab--78 to 83 cm (31 to 33 in); muck, black (10YR 2/1) broken face moist; many very fine roots throughout; noneffervescent; slightly alkaline (pH 7.8); abrupt smooth boundary. (2 to 20 cm, 1 to 8 in)

C1--83 to 112 cm (33 to 44 in); silt loam, very dark gray (10YR 3/1) broken face moist; weak medium lenticular structure; soft, very friable, nonsticky, nonplastic; nonsmeary; few very fine roots throughout; very fine dendritic tubular pores; neutral (pH 6.7); clear smooth boundary. (10 to 30 cm, 4 to 12 in)

C2--112 to 130 cm (44 to 51 in); silt loam, very dark gray (10YR 3/1) broken face moist; weak medium lenticular structure; soft, very friable, nonsticky, nonplastic; nonsmeary; very fine irregular pores; neutral (pH 6.7); clear smooth boundary. (10 to 20 cm, 4 to 8 in)

Cf--130 to 200 cm (51 to 79 in); permanently frozen silt loam, dark gray (10YR 4/1) broken face moist; massive; nonsticky, nonplastic; nonsmeary; very fine irregular pores; noneffervescent; slightly alkaline (pH 7.5) (41 to 135 cm, 16 to 53 in)

TYPE LOCATION: North Copper River Soil Survey Area, Alaska; latitude 62.65933 longitude -144.47378, UTM 6950168.42 north and UTM 629424.09 east, zone 6, Datum WGS84.

RANGE IN CHARACTERISTICS:

Soil moisture regime: udic
Soil temperature regime: gelic
Mean annual soil temperature: -4 to 1 degrees C. (25 to 34 degrees F)
Thickness of organic material: 25 to 39 cm (10 to 15 in)
Thickness of histic epipedon: 25 to 39 cm (10 to 15 in)
Thickness of mollic epipedon: 18 to 50 cm (7 to 20 in)
Depth to permafrost: 65 to 159 cm (26 to 63 in)

Oi, Oe, Oa, Oab horizons:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 1 to 3
Texture: Slightly decomposed organic material, moderately decomposed organic material, highly decomposed organic material.
Organic matter: 60 to 90 percent
Reaction class: moderately acid to slightly alkaline (pH 5.6 to 7.8)

A, A/Osjj horizons:
Hue: 10YR or 2.5Y
Value: 2 to 3
Chroma: 1 to 3
Texture: silt loam, very fine sandy loam
Sand: 15 to 55 percent
Silt: 33 to 80 percent
Clay: 4 to 12 percent
Rock fragments: 0 percent
Organic matter: 2 to 6 percent
Reaction class: slightly acid to slightly alkaline (pH 6.1 to 7.8)

C horizons:
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 1 to 3
Texture: silt loam
Sand: 15 to 45 percent
Silt: 50 to 80 percent
Clay: 3 to 12 percent
Rock fragments: 0 percent
Organic matter: 0.5 to 2 percent
Reaction class: slightly acid to moderately alkaline (pH 6.1 to 8.4)

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Elevation: 200 to 1200 meters (655 to 3935 ft)
Parent material: organic material over silty loess over organic material over silty loess
Landform: hills, hillslopes, river valleys, mountain slopes and hillslopes
Slopes: 0 to 20 percent
Mean annual precipitation: 300 to 800 mm (12 to 31 in)
Mean annual air temperature: -4 to 1 degrees C. (25 to 34 degrees F)
Frost-free period: 32 to 103 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cirquecreek, Ride, Rocklake, Suslota, Taral, and Tasta soils.
Cirquecreek soils are well drained, have a cambic horizon, and occur on saddles and mountain slopes
Ride soils are somewhat excessively drained, have a cambic horizon, and occur on mountain slopes and hillslopes.
Rocklake soils are shallow to bedrock, have little soil development, and occur on ridge lines and escarpments.
Suslota soils are well drained, umbric epipedons, and occur on mountain slopes and hillsides.
Taral soils are well drained, have deep (>40 cm, 16 in thick) mollic epipedon, and occur on mountain and hill slopes greater than 25 percent.
Tasta soils are well drained, have gravelly mollic epipedons, and occur on mountain slopes above 800 m (2600 ft) elevation.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: moderately well
Saturated Hydraulic Conductivity: very high in the Oi, Oe, Oa horizons, moderately high in the A/Oajj1, A/Oajj2, C1, and C2 horizons, high in the Oab horizon, ow in the Cf horizon
Permeability: very rapid in the Oi, Oe, Oa horizons, moderate in the A/Oajj1, A/Oajj2, C1, and C2 horizons, high in the Oab horizon, very slow in the Cf horizon
Runoff: medium

USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: Black spruce and moss

DISTRIBUTION AND EXTENT: MLRA 228 Interior Alaska mountains.
Extent: limited

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

SERIES ESTABLISHED: North Copper River Soil Survey, Alaska, 2024.

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

Particle-size control section: 62 to 137 cm (24 to 54 in)

Histic epipedon: 0 to 37 cm (0 to 15 in) (Oi, Oe, Oa horizons)

Mollic epipedon: 37 to 78 cm (15 to 31 in) (A/Oajj1, A/Oajj2 horizons)

Permafrost: 130 to 200 cm (51 to 79 in) (Cf horizon)

ADDITIONAL DATA:

User pedon Id: 2023AK261220

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National Cooperative Soil Survey
U.S.A.