LOCATION SUSLOTA                 AK

Established Series
SDB/MJS
08/2025

SUSLOTA SERIES

Depth class: very deep
Drainage class: well drained
Parent material: organic material over coarse-loamy noncalcareous loess over gravelly till
Landscape: foothills and mountains
Landform: mountain slopes and hillslopes
Slope: 15 to 70 percent
Mean annual precipitation: about 600 mm (24 in)
Mean annual air temperature: about -3 degrees C (27 F)
Frost-free period: 32 to 71 days

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Humicryepts

TYPICAL PEDON: Suslota sandy loam in a resin birch community on west facing a convex, linear backslope on a slope of 32 percent at an elevation of 1109m (3640 ft).

Oi--0 to 11 cm (0.0 to 4 in); slightly decomposed plant material, very dark brown (7.5YR 2.5/2) moist; very strongly acid (pH 4.6); clear wavy boundary (8 to 14 cm, 3 to 6 in)

A--11 to 18 cm (4 to 7 in); sandy loam, very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; nonsmeary; common very fine and fine roots throughout; common very fine, fine, and few medium tubular pores; very strongly acid (pH 4.9); clear wavy boundary (6 to 12 cm, 2 to 5 in)

2Bw--18 to 47 cm (7 to 19 in); gravelly sandy loam, 60 percent very dark brown (7.5YR 2.5/2) and dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; nonsmeary; common very fine and very few medium roots throughout; common very fine and fine tubular pores; 34 percent gravels by volume; strongly acid (pH 5.1); gradual irregular boundary (23 to 40 cm, 9 to 16 in)

2C--47 to 150 cm (19 to 59 in); very gravelly sandy loam, grayish brown (2.5Y 5/2) moist; massive; soft, very friable, nonsticky, nonplastic; nonsmeary; very few fine roots throughout; few very fine and fine tubular pores; 36 percent gravels by volume; strongly acid (pH 5.4). (84 to 113 cm, 33 to 41 in)

TYPE LOCATION: North Copper River Soil Survey Area, Alaska; latitude 63.09264, longitude -145.41782, UTM 6996894.91north and UTM 579881.39 east, zone 6, Datum WGS84.

RANGE IN CHARACTERISTICS:

Soil moisture regime: udic
Soil temperature regime: cryic
Mean annual soil temperature: 0 to 4 degrees C. (32 to 39 degrees F)
Thickness of organic material: 8 to 14 cm (3 to 6 in)
Thickness of umbric epipedon: 29 to 52 cm (11 to 20 in)
Thickness of cambic horizon: 23 to 40 cm (9 to 16 in)
Depth to lithologic discontinuity: 37 to 66 cm (15 to 26 in)

Oi, Oe horizon:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 1 to 3
Texture: Slightly decomposed organic material, moderately decomposed organic material
Organic matter: 60 to 90 percent
Reaction class: very strongly acid (pH 4.5 to 5)

A horizon:
Hue: 10YR or 2.5Y
Value: 2 to 3
Chroma: 2 to 3
Texture: silt loam, sandy loam
Sand: 23 to 62 percent
Silt: 28 to 67 percent
Clay: 6 to 10 percent
Rock fragments: 0 to 4 percent gravels
Organic matter: 4 to 8 percent
Reaction class: very strongly acid to strongly acid (pH 4.5 to 5.5)

2Bw, Bw horizon:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 2to 3
Texture: silt loam, gravelly silt loam, gravelly sandy loam, very gravelly sandy loam
Sand: 36 to 71 percent
Silt: 19 to 54 percent
Clay: 6 to 10 percent
Rock fragments: 4 to 54 percent
Gravels: 4 to 36 percent
Cobbles: 0 to 18 percent
Organic matter: 1.5 to 3 percent
Reaction class: very strongly acid to strongly acid (pH 4.5 to 5.5)

2C horizon:
Hue: 2.5Y or 5Y
Value: 3 to 5
Chroma: 2 to 4
Texture: very gravelly loam, very gravelly sandy loam
Sand: 50 to 79 percent
Silt: 7 to 41 percent
Clay: 5 to 14 percent
Rock fragments: 21 to 54 percent
Gravels: 21 to 38 percent
Cobbles: 0 to 16 percent
Organic matter: 0.1 to 0.3 percent
Reaction class: strongly acid to moderately acid (pH 5.4 to 6.0)

COMPETING SERIES: These are the Alterationcreek (AK), Atayak (AK), Bergbay (AK), Buell (AK), Ibach (AK), Kinak (AK), Mccall (AK), Moran (AK), Springcamp (AK), Tolstoipoint (AK), and Walcott (AK) soils
Alterationcreek and Atayak soils have a lithic contact between 100 and 200 cm.
Berbay soils lack a loess cap and are moderately deep.
Buell, Mccall, Moran, Suslota, Tolstoipint, and Walcott soils do not have a loess cap.
Ibach soils have bolders in the top 100 cm (39 in) and occur at elevations between 2 and 45 m. (5 and 150 ft)
Springcamp soils have a paralithic contact.

GEOGRAPHIC SETTING:
Elevation: 600 to 1600 meters (1970 to 5250 ft)
Parent material: organic material over coarse-loamy noncalcareous loess over gravelly till
Landform: mountain slopes and hillslopes
Slopes: 15 to 70 percent
Mean annual precipitation: 400 to 800 mm (16 to 31 in)
Mean annual air temperature: -4 to -2 degrees C. (25 to 28 degrees F)
Frost-free period: 32 to 71 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cirquecreek, Fields, Fireweed, Geist, Haleycreek, Summitlake, Tasta, and Townlake soils.
Cirquecreek soils lacks an umbric epipedon and occur on saddles and mountain slopes.
Fields have lithic contact within 200 cm (79 in) and occur on mountains.
Geist soils are somewhat excessively drained, have a spodic horizon, and occur in eolian deposits over sandy outwash on hills and outwash plains.
Haleycreek soils have a cobbly sandy loam surface texture, it has a mollic epipedon, lacks a lithic contact, and occur on hillslopes of mountains and river valleys.
Summitlake soils are poorly drained, lack a umbric epipedon, and occur in lake plains and depressions in foothills.
Tasta soils have a mollic epipedon and occur on mountain slopes above 800 m (2600 ft) elevation.
Townlake soils are moderately well drained, have permafrost, have cryoturbation, have folistic and mollic epipedons, and occur on hills, mountain slopes, and river valleys.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: well drained
Saturated Hydraulic Conductivity: very high in the Oi horizon, high in the A, 2Bw, and 2C horizons.
Permeability: very rapid in the Oi horizon, moderately rapid in the A, 2Bw, and 2C horizons.
Runoff: medium

USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: resin birch, black crowberry, moss

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

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: 36 to 111 cm (14 to 44 in)

Umbric epipedon: 11to 47 cm (4 to 19 in) (A and 2Bw horizons)

Cambic horizon: 18 to 47 cm (7 to 19 in) (2Bw horizon)

Lithologic discontinuity: 47 to 150 cm (19 to 59 in) (2Bw and 2C horizons)

ADDITIONAL DATA:

User pedon Id: 2023AK261365

---

National Cooperative Soil Survey
U.S.A.