LOCATION KUSWASH                 AK

Established Series
Rev. MHC/DLM
05/2022

KUSWASH SERIES

Depth class: moderately deep to permafrost
Drainage class: poorly drained
Landforms: hills; outwash plains
Parent material: silty eolian deposits over sandy and silty outwash
Elevation: 2,546 to 2,982 feet (776 to 909 m)
Slope: 0 to 5 percent
Annual precipitation: 23 to 31 inches (596 to 776 mm)
Annual temperature: 25 degrees F (-4 degrees C)
Frost-free period: 50 to 70 days

TAXONOMIC CLASS:

TYPICAL PEDON: Kuswash peat - on a slope of 2 percent under shrub birch-mixed ericaceous shrub/sedge scrub. (All colors are for moist soil)

Oi--0 to 10 inches (0 to 25 cm); reddish yellow (7.5YR 6/6) peat; many very fine and fine roots; extremely acid (pH 4.4); clear wavy boundary.

A--10 to 13inches (25 to 33 cm); dark brown (10YR 3/3) silt loam; weak medium granular structure; very friable, nonsticky and nonplastic; common very fine and fine roots; extremely acid (pH 4.1); clear wavy boundary.

2C--13 to 25 inches (33 to 64 cm); brown (10YR 5/3) stratified fine sand to silt; massive; very friable, nonsticky and nonplastic; few very fine and fine roots; 5 mm dark yellowish brown (10YR 4/4) high chroma redox concentrations (approximately 15 percent of horizon); very strongly acid (pH 4.6); clear wavy boundary.

2Cf--25 to 60 inches (64 to 152 cm); brown (10YR 5/3) permanently frozen stratified fine sand to silt; very strongly acid (pH 4.6).

TYPE LOCATION: Delta River Survey Area, Alaska; in the Tangle Lakes Area about 0.65 miles west of Upper Tangle Lake; UTM coordinates: Zone 6, Easting 546460, Northing 6986707.

RANGE IN CHARACTERISTICS:

Soil moisture class: aquic
Average annual soil temperature: 32 to 30 degrees F (-0.1 to -1.0 degrees C)
Mean summer soil temperature: 36 to 39 degrees F. (2 to 4 degrees C)
Depth to permafrost: 20 to 31 inches (50 to 79 cm)

Oi horizon:
Colorhue of 5YR to 10YR; value of 2 to 3; chroma of 1 to 4
Organic matter content65 to 90 percent
Reactionextremely acid to strongly acid

A horizon:
Colorvalue of 2 or 3; chroma of 1 to 3
Clay content0 to 10 percent
Silt content55 to 75 percent
Sand content15 to 35 percent
Organic matter content2 to 6 percent
Rock fragments0 to 5 percent rounded gravel; 0 to 2 percent rounded cobbles
Reactionextremely acid to very strongly acid

C or Cf horizon:
Colorhue of 10YR or 2.5Y; value of 4 or 5; chroma of 2 or 3
Clay content0 to 10 percent
Silt content55 to 75 percent
Sand content15 to 35 percent
Organic matter content0 to 1 percent
Rock fragments0 to 5 percent rounded gravel; 0 to 2 percent rounded cobbles
Reactionvery strongly acid to moderately acid

COMPETING SERIES: These are the Boldrin and Dirrant series. Boldrin and Dirrant soils have a mean annual soil temperature less than -2 degrees C.

GEOGRAPHIC SETTING:
Landforms: hills; outwash plains
Parent material: silty eolian deposits over sandy and silty outwash
Elevation: 2,546 to 2,982 feet (776 to 909 m)
Slope: 0 to 5 percent
Annual precipitation: 23 to 31 inches (596 to 776 mm)
Annual temperature: 25 degrees F (-4 degrees C)
Frost-free period: 50 to 70 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Schleyer and Turbellina soils. Schleyer soils are somewhat excessive drained, very deep, and occur on mountains and alluvial fans. Turbellina soils are very poorly drained, shallow or moderately deep to permafrost, and occur on outwash plains.

DRAINAGE AND PERMEABILITY: Poorly drained, very high runoff. Saturated hydraulic conductivity is moderately high to high above the permafrost and very low in the permafrost.

USE AND VEGETATION: Used for wildlife habitat and recreation. Native vegetation is shrub birch-mixed ericaceous shrub/sedge scrub.

DISTRIBUTION AND EXTENT: MLRA 228, Interior Alaska Mountains, Alaska. The series is of small extent.

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

SERIES ESTABLISHED: Delta River Area, Alaska, 2005

REMARKS: Diagnostic features and horizons recognized in this profile include:
Depth to permafrost: 25 to 60 inches. (2Cf horizon)
Histic epipedon: 0 to 10 inches. (Oi horizon)
Redoximorphic concentrations: 13 to 25 inches. (2C horizon)
Coarse-loamy particle size control section: 10 to 40 inches below the mineral soil surface
Temperature regime: pergelic
Moisture regime: aquic.

ADDITIONAL DATA:

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National Cooperative Soil Survey
U.S.A.