LOCATION SQUIRRELCREEK AK

Established Series
SDB/MJS
08/2025

SQUIRRELCREEK SERIES

Depth class: very deep
Drainage class: somewhat excessively drained
Parent material: herbaceous organic material over sandy and silty alluvium
Landscape: foothills, outwash plains, and lake plains
Landform: floodplains, outwash plains, rivers, river valleys, and bluffs.
Slope: 0 to 15 percent
Mean annual precipitation: about 500 mm (20 in)
Mean annual air temperature: about -3 degrees C (27 F)
Frost-free period: 20 to 103 days

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, nonacid Typic Cryorthents

TYPICAL PEDON: Squirrelcreek loamy very fine sands in a white spruce community on an outwash plain on a slope of 3 percent at an elevation of 667m (2190 ft).

Oi--0 to 7 cm (0 to 3 in); slightly decomposed plant material, very dark brown (7.5YR 2.5/3) moist; common very fine, fine, medium, and coarse roots throughout; neutral (pH 6.8); abrupt wavy boundary (5 to 9cm, 2 to 4 in)

Bw/A--7 to 19 cm (3 to 7 in); loamy very fine sand, 60 percent very dark grayish brown (2.5Y 3/2) and 40 percent very dark brown (7.5YR 2.5/2) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky, nonplastic; nonsmeary; common very fine, fine, and medium roots throughout; common very fine, fine, and medium tubular pores; neutral (pH 6.8); abrupt wavy boundary. (10 to 14 cm, 4 to 6 in)

C1--19 to 49 cm (7 to 19 in); very fine sandy loam, olive (5Y 5/3) moist; massive; soft, very friable, nonsticky, nonplastic; nonsmeary; common very fine and fine roots throughout; common very fine and fine tubular pores; 5 percent gravel by volume; neutral (pH 6.7); gradual wavy boundary. (28 to 43 cm, 11 to 17 in)

C2--49 to 77 cm (19 to 30 in); very fine sandy loam, olive gray (5Y 4/2) moist; massive; soft, very friable, nonsticky, nonplastic; nonsmeary; common very fine roots throughout; common very fine tubular pores; 12 percent gravel by volume; neutral (pH 6.7); gradual wavy boundary.

C3--77 to 200 cm (30 to 79 in); very fine sandy loam, olive gray (5Y 4/2) moist; massive; soft, very friable, nonsticky, nonplastic; nonsmeary; common very fine roots throughout; common very fine tubular pores; 10 percent gravel by volume; noneffervescent; slightly alkaline (pH 7.5). (142 to 165 cm, 56 to 65 in)

TYPE LOCATION: North Copper River Soil Survey Area, Alaska; latitude 61.6062500, longitude -145.1822500, UTM 6831663.02 north and UTM 596426.39 east, zone 6, Datum WGS84.

RANGE IN CHARACTERISTICS:

Soil moisture regime: udic
Soil temperature regime: cryic
Mean annual soil temperature: 0 to 5 degrees C. (32 to 41 degrees F)
Thickness of organic material: 5 to 9 cm (2 to 4 in)
Thickness of ochric epipedon: 15 to 23 cm (6 to 9 in)

Oi, Oe, Oa example horizon:
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)

Bw/A or A horizon:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 1 to 2
Texture: loamy very fine sand
Sand: 75 to 82 percent
Silt: 10 to 20 percent
Clay: 2 to 8 percent
Organic matter: 4 to 6 percent
Reaction class: moderately acid to slightly alkaline (pH 5.6 to 7.8)

C horizon:
Hue: 2.5Y or 5Y
Value: 4 to 6
Chroma: 1 to 3
Texture: very fine sandy loam
Sand: 55 to 68 percent
Silt: 16 to 37 percent
Clay: 8 to 16 percent
Rock fragments: 3 to 13 percent gravels
Organic matter: 0.5 to 2 percent
Reaction class: moderately acid to slightly alkaline (pH 5.4 to 7.8)

Some pedons have a Bw horizon with a texture of silt loam, sandy loam, or loamy sand; a hue of 7.5 YR or 10YR, value of 4 to 5, and a chroma of 3 to 6.

COMPETING SERIES: These are the Baldy (AZ) and Emestine (AK) soils.
Baldy soils have a mean annual temperature of 3 to 7 degrees C (38 to 45 degrees F) and occur at elevations between 2743 to 3503 m (9000 and 11500 ft).
Emestine soils are well drained, have sandy till parent material, and occur on mountain slopes.

GEOGRAPHIC SETTING:
Elevation: 200 to 1000 meters (655 to 3280 ft)
Parent material: herbaceous organic material over sandy and silty alluvium
Landform: floodplains, outwash plains, rivers, river valleys, and bluffs.
Slopes: 0 to 15 percent
Mean annual precipitation: 300 to 1400 mm (12 to 55 in)
Mean annual air temperature: -5 to -1 degrees C. (23 to 30 degrees F)
Frost-free period: 20 to 103 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ahtell, Basaltlake, Dodger, Klawasi, Octopuslake, and Summitlake soils.
Ahtell soils are well drained, have folistic and umbric epipedons, and occur on hill tops, and hillside positions.
Basaltlake soils are well drained, form in silty deposited over till, and occur on mountains.
Dodger soils are an organic permafrost soil and occur on outwash terraces on mountains.
Klawasi soils are very poorly drained, have permafrost , have histic epipedons and a loess cap over clayey lacustrine sediments, and occur on lacustrine terraces.
Octopuslake soils are very poorly drained, are organic soil, have a mucky peat surface horizon, and occur on hills and in depressions on foothills and mountains.
Summitlake soils are poorly drained mineral soils and occur in lake plains and depressions in foothills.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: somewhat excessively drained
Saturated Hydraulic Conductivity: very high in the Oi and Bw/A horizons, high in the C1 and C2 horizons.
Permeability: very rapid in the Oi and Bw/A horizons, moderately rapid in the C1 and C2 horizons.
Runoff: low

USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: white spruce, bog blueberry and feathermoss

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: 32 to 107 cm (13 to 42 in)

Ochric epipedon: 0 to 21 cm (0 to 8 in) (Oi and Bw/A horizon)

ADDITIONAL DATA:

User pedon Id: 2022AK261512

National Cooperative Soil Survey
U.S.A.