LOCATION COPPERCENTER            AK

Established Series
SDB/MJS
08/2025

COPPERCENTER SERIES

Depth class: moderately deep
Drainage class: poorly drained
Parent material: organic material over silty loess
Landscape: mountains and foothills
Landform: hills and hillslopes
Slope: 0 to 10 percent
Mean annual precipitation: about 350 mm (14 in)
Mean annual air temperature: about 0 degrees C. (32 degrees F.)
Frost-free period: 32 to 103 days

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, nonacid, subgelic Typic Historthels

TYPICAL PEDON: Coppercenter mucky peat in an alder willow community on a south-east facing terrace riser with a slope of 7 percent at an elevation of 331 m (1085 ft)

Oe--0 to 24 cm (0 to 9 in); mucky peat, very dark brown (10YR 2/2) broken face moist; many very fine and common fine roots throughout; many very fine tubular and common fine tubular pores; neutral (pH 7.2); clear smooth boundary (18 to 26 cm, 7 to 10 in).

Oa--24 to 36 cm (9 to 14 in); muck, black (10YR 2/1) broken face moist; common very fine roots throughout; common very fine tubular pores; noneffervescent; slightly alkaline (pH 7.6); abrupt smooth boundary (10 to 13 cm, 4 to 5 in)

A--36 to 72 cm (14 to 28 in); loamy very fine sand, 80 percent very dark grayish brown (10YR 3/2) broken face and 20 percent dark grayish brown (10YR 4/2) broken face moist; massive; soft, very friable, nonsticky, nonplastic; nonsmeary noneffervescent; slightly alkaline (pH 7.4); abrupt smooth boundary (28 to 40cm, 11 to 16 in)

Cf--72 to 150 cm (28 to 59 in); dark grayish brown (2.5Y 4/2) broken face moist; weak, fine subangular blocky; soft, very friable, nonsticky, nonplastic; nonsmeary; very fine low-continuity tubular pores; noneffervescent; slightly alkaline (pH 7.4); abrupt boundary (71 to 94 cm, 28 to 37 in).

TYPE LOCATION: North Copper River Soil Survey Area, Alaska; latitude 61.54626, longitude -144.43027, UTM 6826328.45 north and UTM 636567.96 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 histic epipedon: 28 to 39 cm (11 to 15 in)
Thickness of mollic epipedon: 28 to 40 cm (11 to 15 in)
Depth to Aquic Conditions: 18 to 26 cm (7 to 10 in)
Depth to permafrost: 72 to 150 cm (28 to 59 in)

Oe and Oa horizon:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 1 to 2
Texture: mucky peat, muck
Organic matter: 60 to 90 percent
Reaction class: neutral to slightly alkaline (pH 6.6 to 7.8)

Bw and A horizons:
Hue: 10YR or 2.5Y
Value: 3 to 4
Chroma: 2 to 3
Texture: loamy very fine sand, silt loam, very fine sandy loam
Sand: 8 to 86 percent
Silt: 2 to 80 percent
Clay: 6 to 12 percent
Organic matter: .7 to 1.3 percent
Reaction class: slightly alkaline (pH 7.4 to 7.8)

C and Cf horizon:
Hue: 10YR or 2.5Y
Value: 4 to 5
Chroma: 1 to 2
Texture: loamy very fine sand, silt loam, very fine sandy loam
Sand: 8 to 86 percent
Silt: 2 to 80 percent
Clay: 6 to 12 percent
Organic matter: 0.2 to 0.55 percent
Reaction class: neutral to slightly alkaline (pH 7.0 to 7.8)

COMPETING SERIES: These are the Goldenorth, Ricepeak, and Tseenjik soils.
Goldenorth soils are very poorly drained, have a loess cap over gravely till, and occur on hillslopes in valleys.
Ricepeak soils have alluvium parent material and occur on flats and till plains.
Tseenjik soils lack a mollic epipedon and occur on floodplains.

GEOGRAPHIC SETTING:
Elevation: 200 to 600 meters (655 to 1970 ft)
Parent material: organic material over silty loess
Landform: hillslopes and hills
Slopes: 0 to 10 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 Drashner, Kluna, Rocklake, Taral, and Tonsina soils.
Drashner soils are somewhat poorly drained, have a histic epipedon, and occur on mountains and hillslopes.
Kluna soils are well drained, have stratified horizons of sandy and silty alluvium, and occur on stream terraces and floodplains.
Rocklake soils are shallow to bedrock and typically occur on ridge lines and escarpments.
Taral soils are well drained, have a deep (>40 cm, 16 in thick) mollic epipedon, and occur on mountain and hill slopes greater than 25 percent.
Tonsina soils are well drained, have a deep (>40 cm, 16 in thick) mollic epipedon, and occur on loess covered glacial till in till plains, hills and drumlins.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: poorly drained
Saturated Hydraulic Conductivity: high in the Oe and Oa horizons, very high in the Bw horizon, low in the Cf horizon.
Permeability: Moderately rapid in the Oe and Oa horizons, very rapid in the Bw horizon, very slow in the Cf horizon.
Runoff: very high

USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: Alder and Grey leaf willow

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: 61 to 136 cm (24 to 54 in)

Histic epipedon: 0 to 36 cm (0 to 14 in) (Oa and Oe horizon)

Mollic horizon: 36 to 72 cm (14 to 28 in) (Bw horizon)

Aquic conditions: 24 to 72 cm (9 to 28 in) (Oa and Bw horizons)

Permafrost: 72 to 150 cm (28 to 59 in) (Cf horizon)

ADDITIONAL DATA:

User pedon Id: 2022AK261535

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National Cooperative Soil Survey
U.S.A.