LOCATION TUKSUK                  AK

Established Series
Rev. MHC/DLM
02/2022

TUKSUK SERIES

Depth class: moderately deep
Drainage class: very poorly drained
Landforms: mountains
Parent material: silty eolian deposits over gravelly colluvium
Elevation: 531 to 971 feet
Slope: 6 to 20 percent
Annual precipitation: 23.5 to 27.4 inches
Annual temperature: 23.0 to 24.8 degrees F
Frost-free period: 60 to 90 days

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

TYPICAL PEDON: Tuksuk mucky silt loam - on a slope of 8 percent willow/mixed grass-forb scrub. (All colors are for moist soil)

Oe--0 to 4 inches; black (10YR 2/1) moderately decomposed plant material; many very fine and fine, common medium and few coarse roots; neutral (pH 6.6); clear wavy boundary.

Oa--4 to 7 inches; black (10YR 2/1) highly decomposed plant material; many very fine and fine, common medium and few coarse roots; neutral (pH 6.6); clear wavy boundary.

A--7 to 8 inches; very dark brown (10YR 2/2) mucky silt loam; very friable, nonsticky and nonplastic; many very fine and fine, few medium and few coarse roots; neutral (pH 6.7); clear wavy boundary.

Cg1--8 to 15 inches; gray (2.5Y 5/1) silt loam; very friable, nonsticky and nonplastic; common very fine and fine and few medium roots; 2 mm dark yellowish brown (10YR 4/6) high chroma redox concentrations (approximately 15 percent of horizon); slightly acid (pH 6.3); abrupt wavy boundary.

2Cg2--15 to 26 inches; dark gray (5Y 4/1) channery loam; friable, nonsticky and nonplastic; 15 percent channers; 2 mm strong brown (7.5YR 4/6) high chroma redox concentrations (approximately 20 percent of horizon); neutral (pH 6.6); gradual wavy boundary.

2Cg3--26 to 39 inches; gray (5Y 5/1) and olive (5Y 4/3) channery loam; friable, nonsticky and nonplastic; 15 percent channers; 2 mm strong brown (7.5YR 4/6) high chroma redox concentrations (approximately 10 percent of horizon); slightly acid (pH 6.4); clear wavy boundary.

2Cr--39 to 60 inches; fractured bedrock.

TYPE LOCATION: Steward River Training Site, Alaska; UTM coordinates: Zone 3, Easting 477849, Northing 7182408.

RANGE IN CHARACTERISTICS:
Soil moisture class: aquic
Average annual soil temperature: about 31 degrees F.
Mean summer soil temperature: about 35 degrees F.
Depth to bedrock (paralithic): 32 to 60 inches
Depth to strongly contrasting textural stratification: 5 to 17 inches

Oe, Oa horizon:
Hue: 7.5YR or 10YR
Value: 2 or 2.5
Chroma: 1 or 2
Texture: mucky peat, muck
Organic matter content: 65 to 90 percent
Reaction: moderately acid to neutral

A horizon:
Chroma: 1 or 2
Texture: mucky silt loam, silt loam
Clay content: 0 to 10 percent
Silt content: 55 to 75 percent
Sand content: 15 to 35 percent
Organic matter content: 8 to 12 percent
Rock fragments: 0 to 5 percent subangular very strongly cemented channers
Reaction: moderately acid to neutral

2Cg horizon:
Hue: 2.5Y or 5Y
Value: 4 or 5
Chroma: 1 or 2
Texture: channery loam, very channery loam
Clay content: 0 to 10 percent
Silt content: 15 to 50 percent
Sand content: 30 to 75 percent
Rock fragments: 0 to 25 percent subangular strongly cemented channers, 0 to 10 percent subangular strongly cemented flagstones
Reaction: Reaction: slightly acid to neutral

COMPETING SERIES: There are no competing series in this classification.

GEOGRAPHIC SETTING:
Landforms: mountains
Parent material: silty eolian deposits over gravelly colluvium
Elevation: 531 to 971 feet
Slope: 6 to 20 percent
Annual precipitation: 23.5 to 27.4 inches
Annual temperature: 23.0 to 24.8 degrees F
Frost-free period: 60 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Kiglauik and Sinuktuk soils. Kiglauik soils are somewhat poorly drained, moderately deep, and occur on mountains. Sinuktuk soils are well drained, moderately deep, and occur on mountains.

DRAINAGE AND PERMEABILITY: Very poorly drained, very high runoff. Saturated hydraulic conductivity is moderately high to high in the soil profile and very low in the bedrock.

USE AND VEGETATION: Used for military use and wildlife habitat. Native vegetation is willow/mixed grass-forb scrub.

DISTRIBUTION AND EXTENT: MLRA 240, Nulato Highland-Southern Seward Peninsula Highlands, Alaska. The series is of small extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA

SERIES ESTABLISHED: Steward River Training Site, Alaska, 2005

REMARKS: Diagnostic features and horizons recognized in this profile include
Paralithic contact: 39 inches. (Cr horizon)
No diagnostic horizons:
Redoximorphic features: 8 to 39 inches. (Cg1, 2Cg2, and 2Cg3 horizons)
Lithologic discontinuity: At the upper boundary of 2Cg2 horizon
Coarse-loamy particle size control section: 14 to 39 inches
Temperature regime: cryic
Moisture regime: aquic.

ADDITIONAL DATA:

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National Cooperative Soil Survey
U.S.A.