LOCATION PINGUK                  AK

Established Series
Rev. MHC/DLM
02/2022

PINGUK SERIES

Depth class: very deep
Drainage class: somewhat poorly drained
Landforms: swales on alluvial fans
Parent material: silty eolian deposits over gravelly alluvium
Elevation: 381 to 564 feet
Slope: 2 to 5 percent
Annual precipitation: 22 to 27 inches
Annual temperature: 23 to 25 degrees F
Frost-free period: 60 to 90 days

TAXONOMIC CLASS:

TYPICAL PEDON: Pinguk silt loam- on a slope of 2 percent under willow ericaceous shrub scrub. (All colors are for moist soil)

Oe--0 to 2 inches; very dark brown (7.5YR 2.5/3) moderately decomposed plant material; many very fine and fine and common medium roots; very strongly acid (pH 4.6); clear smooth boundary.

A--2 to 5 inches; very dark brown (10YR 2/2) silt loam; very friable, nonsticky and nonplastic; many very fine and fine and common medium roots; 2 percent gravel; very strongly acid (pH 4.8); clear smooth boundary.

2Bw--5 to 15 inches; brown (10YR 4/3) gravelly loam; friable, nonsticky and nonplastic; common very fine and fine and few medium roots; 15 percent gravel, 2 percent cobbles; moderately acid (pH 5.6); clear smooth boundary.

2C1--15 to 21 inches; olive gray (5Y 4/2) very cobbly sandy loam; friable, nonsticky and nonplastic; 15 percent gravel, 35 percent cobbles; moderately acid (pH 5.6); gradual smooth boundary.

2C2--21 to 60 inches; olive (5Y 4/3) very cobbly sandy loam; friable, nonsticky and nonplastic; 15 percent gravel, 40 percent cobbles; moderately acid (pH 5.6).

TYPE LOCATION: Steward River Training Site, Alaska; UTM coordinates: Zone 3, Easting 476244, Northing 7186125

RANGE IN CHARACTERISTICS:
Soil moisture class: oxyaquic
Average annual soil temperature: about 31 degrees F.
Mean summer soil temperature: about 35 degrees F.
Depth to strongly contrasting textural stratification: 4 to 7 inches

Oi horizon:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 2 or 3
Organic matter content: 85 to 95 percent
Reaction: extremely acid to very strongly acid

A horizon:
Value: 2 to 3
Chroma: 2 or 3
Texture: silt loam
Clay content: 0 to 10 percent
Silt content: 50 to 80 percent
Sand content: 15 to 50 percent
Organic matter content: 2 to 8 percent
Rock fragments: 0 to 5 percent strongly cemented channers, 0 to 2 percent strongly cemented flagstones
Reaction: extremely acid to strongly acid

2Bw horizon:
Hue: 10YR or 2.5Y
Value: 3 or 4
Chroma: 3 or 4
Texture: cobbly sandy loam, very cobbly sandy loam, gravelly loam
Clay content: 5 to 25 percent
Silt content: 10 to 45 percent
Sand content: 40 to 75 percent
Organic matter content: 0 to 2 percent
Rock fragments: 0 to 30 percent subrounded very strongly cemented gravel, 0 to 5 percent subrounded very strongly cemented cobbles
Reaction: very strongly acid to slightly acid

2C horizon:
Hue: 2.5Y or 5Y
Value: 4 or 5
Chroma: 2 or 3
Texture: very cobbly sandy loam, very gravelly sandy loam
Clay content: 0 to 20 percent
Silt content: 10 to 40 percent
Sand content: 45 to 80 percent
Rock fragments: 15 to 30 percent subrounded very strongly cemented gravel, 5 to 40 percent subrounded very strongly cemented cobbles
Reaction: very strongly acid to slightly acid

COMPETING SERIES: These are the McKinley and Tisuk series. McKinley soils are moderately deep to weather bedrock. Tisuk soils do not have saturated horizons in the spring.

GEOGRAPHIC SETTING:
Landforms: swales on alluvial fans
Parent material: silty eolian deposits over gravelly alluvium
Elevation: 381 to 564 feet
Slope: 2 to 5 percent
Annual precipitation: 22 to 27 inches
Annual temperature: 23 to 25 degrees F
Frost-free period: 60 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Agiapuk, Boldrin, and Nuluk soils. Agiapuk soils are well drained, very deep, and occur on alluvial fans. Boldrin soils are very poorly drained, shallow to moderately deep to permafrost, and occur on mountain footslopes and toeslopes. Nuluk soils are somewhat poorly drained, very deep, and occur on flood plains on alluvial fans.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained, very high runoff. Saturated hydraulic conductivity is moderately high to high.

USE AND VEGETATION: Used for military use and wildlife habitat. Native vegetation is willow ericaceous shrub scrub.

DISTRIBUTION AND EXTENT: MLRA 240, Nulato Hills-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:
Cambic horizon: 5 to 15 inches. (2Bw horizon)
Lithologic discontinuity: At the upper boundary of A horizon
Loamy-skeletal particle size control section: 10 to 40 inches below the mineral soil surface
Temperature regime: cryic

ADDITIONAL DATA:

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National Cooperative Soil Survey
U.S.A.