LOCATION CHAKINA                 AK

Established Series
SDB/MJS
08/2025

CHAKINA SERIES

Depth class: deep
Drainage class: somewhat poorly drained
Parent material: organic material over silty loess over loamy till
Landscape: mountains
Landform: perennial streams on mountain slopes
Slopes: 0 to 10 percent
Mean annual precipitation: about 350 mm (14 in)
Mean annual air temperature: about -3 degrees C. (27 degrees F)
Frost-free period: 40 to 75 days

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

TYPICAL PEDON: Chakina muck in a willow community on an east facing convex, convex footslope on a slope of 7 percent at an elevation of 1057m (3470 ft).

Oi--0 to 9 cm (0 to 3.5 in); peat, dark brown (7.5YR 3/3) rubbed moist; nonsticky, nonplastic; common very fine and fine, and few medium roots throughout; very strongly acid (pH 5.0); clear smooth boundary (8 to 14 cm, 3 to 6 in).

Oe--9 to 14 cm (3.5 to 5.5 in); mucky peat, very dark brown (7.5YR 2.5/2) rubbed moist; nonsticky, nonplastic; few very fine roots throughout; strongly acid (pH 5.3); clear smooth boundary (4 to 6 cm, 2 in).

Oa--14 to 25 cm (5.5 to 10 in); muck, black (7.5YR 2.5/1) rubbed moist; nonsticky, nonplastic; few very fine roots throughout; very strongly acid (pH 5.0); clear wavy boundary (10 to 13 cm, 4 to 5 in).

A/Cg/Oajj--25 to 40 cm (10 to 16 in); silt loam, loam, muck, 66 percent black (7.5YR 2.5/1) broken face and 33 percent dark grayish brown (2.5Y 4/2) broken face moist; weak medium lenticular structure; soft, very friable, nonsticky, nonplastic; nonsmeary; interstitial pores; 20 percent medium irregular yellowish brown (10YR 5/6) iron-manganese concretions in matrix; 8 percent subrounded gravels by volume; strongly acid (pH 5.4); clear smooth boundary (14 to 18 cm, 6 to 7 in).

Cg--40 to 140 cm (16 to 55 in); loam, dark grayish brown (2.5Y 4/2) broken face moist; soft, very friable, nonsticky, nonplastic; nonsmeary; few very fine interstitial pores; 5 percent fine irregular yellowish brown (10YR 5/6) iron-manganese concretions in matrix; 12 percent subrounded gravels by volume; very strongly acid (pH 4.6). (94 to 102 cm, 37 to 40 in).

Cf--140 to 165 cm (55 to 63 in); loam, dark grayish brown (2.5Y 4/2) broken face moist; massive; soft, very friable, nonsticky, nonplastic; nonsmeary; interstitial pores; 5 percent fine irregular yellowish brown (10YR 5/6) iron-manganese concretions in matrix; 12 percent subrounded gravels by volume; very strongly acid (pH 4.6). (25 cm, 10 in).

TYPE LOCATION: North Copper River Soil Survey Area, Alaska; latitude 61.96993, longitude -147.18875, UTM 6837287.39 north and UTM 490104.00 east, zone 6, Datum WGS84.

RANGE IN CHARACTERISTICS:

Soil moisture regime: aquic
Soil temperature regime: gelic
Mean annual soil temperature: -4 to 1 degrees C. (25 to 34 degrees F)
Thickness of histic epipedon: 20 to 33 cm (8 to 13 in)
Thickness of cryoturbated horizon: 14 to 18 cm (6 to 7 in)
Depth to redoximorphic concentrations: 22 to 33 cm (9 to 13 in)
Depth to redoximorphic depletions: 36 to 51 cm (14 to 20 in)
Depth to permafrost: 130 to 152 cm (51 to 60 in)

Oi, Oe, and Oa horizons:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 1 to 3
Texture: peat, mucky peat, muck
Organic matter: 60 to 90 percent
Reaction class: very strongly acid to strongly acid (pH 4.5 to 5.5)

Cryoturbated horizon:
Matrix color: Hue of 2.5Y or 5Y, value of 4 to 5, chroma of 2 to 3
Redox concentration: Hue of 7.5YR or 10 YR, value of 4 or 5, chroma 5 to 6.
Organic concentrations: Hue of 7.5YR or 10YR, value of 2 to 3, chroma of 1 to 3.
Texture: Mucky silt loam and stratified muck, loam, and silt loam.
Sand: 20 to 43 percent
Silt: 48 to 74 percent
Clay: 6 to 12 percent
Rock fragments: 4 to 10 percent gravels
Organic matter: 6 to 12 percent
Reaction class: strongly acid (pH 5.1 to 5.5)

Cg and Cf horizon:
Hue: 2.5Y or 5Y
Value: 4 to 6
Chroma: 1 to 2
Texture: loam
Sand: 40 to 51 percent
Silt: 32 to 48 percent
Clay: 11 to 17 percent
Rock fragments: 8 to 14 percent gravels
Organic matter: 0 to 1 percent
Reaction class: very strongly acid (pH 4.5 to 5.0)

COMPETING SERIES: These are Apun (AK), Crosswind (AK), Ellisgap (AK), Foggypass (AK), Pupcreek (AK), Saintelias (AK), Slatka (AK), and Tulebagh (AK) series.
Apun soils are poorly drained, lack a till in the lower horizons, and occur on river valley terraces.
Crosswind soils are poorly drained, have a mollic epipedon, have permafrost within 108 cm, and occur on river valleys and bluffs in lake plains.
Ellisgap soils have permafrost within 75 cm (30 in) and lack coarse fragments in all horizons.
Foggypass soils are poorly drained and lack a loess cap.
Pupcreek soils are poorly drained, have colluvium parent material, and occur on hills.
Saintelias soils are poorly drained, form over lacustrine sediments, and occur on terraces and in river valleys.
Slatka soils have permafrost within 64 cm (25 in) of the surface and silt loam or fine sandy loam parent material textures.
Tulebagh soils are poorly drained, have pH values greater than 7.0 in the cryoturbated horizons, and occur on stream terraces and interdunes on alluvial plains.

GEOGRAPHIC SETTING:
Elevation: 800 to 1200 meters (2625 to 3935 ft)
Parent material: organic material over silty loess over loamy till
Landform: perennial streams on mountain slopes
Slopes: 1 to 10 percent
Mean annual precipitation: 300 to 400 mm (12 to 16 in)
Mean annual air temperature: -4 to -2 degrees C. (25 to 28 degrees F)
Frost free period: 40 to 75 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ahtell, Chisana, and Schleyer series.
Ahtell soils are well drained, lack permafrost, have folistic and umbric epipedons, and occur on hill tops, and hillside positions.
Chisana soils are poorly drained, lack cryoturbation, have a cambic horizon, and occur on mountain slopes.
Schleyer soils are somewhat excessively drained, lack permafrost, have albic horizons, and occur in mountain valleys and on fan remnants.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: somewhat poorly
Saturated Hydraulic Conductivity: High in the O horizons, cryoturbated horizons, and Cg horizon and low in Cf horizon.
Permeability: Moderately rapid in the O horizons, cryoturbated horizons, and Cg horizon very slow in Cf horizon.
Runoff: very high

USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: Tealeaf willow, bog blueberry, 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: 50 to 125 cm (20 to 49 in)

Histic epipedon: 0 to 25 cm (0 to 10 in) (O horizons)

Cryoturbated horizon: 25 to 40 cm (10 to 16 in) (A/C/Oagjj horizon)

Aquic conditions: 25 to 140 cm (10 to 55 in) (A/C/Oagjj, and Cg horizons)

Permafrost: 140 to 165 cm (55 to 65 in) (Cf horizon)

ADDITIONAL DATA:

User pedon Id: 2023AK170157

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National Cooperative Soil Survey
U.S.A.