LOCATION OSKAWALIKFAMILY AK
Tentative Series
Rev. JPM
02/2022
OSKAWALIKFAMILY SERIES
Note: Used as a placeholder series until a series is established under the family class
Depth class: Very deep
Drainage class: Very poorly to poorly drained
Parent material: loess and alluvium
Landform: toeslopes of hills, and floodplains
Slopes: 0 to 9 percent
Mean annual precipitation: about 16 inches
Mean annual temperature: about 29 degrees F.
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, nonacid Fluvaquentic Cryaquepts
TYPICAL PEDON: Oskawalikfamily silt loam - on a slope of 9 percent on a mountain footslope under scrub vegetation at 1280 feet elevation. (All colors are for moist soil unless noted)
Oi--0 to 2 inches (0 to 5 cm) 49 percent black (10YR 2/1) and 50 percent very dark brown (10YR 2/2) peat; many very fine and fine roots, and common medium and coarse roots; slightly acid, pH 6.5; abrupt smooth boundary.
AC--2 to 6 inches (5 to 14 cm) brown (10YR 4/3) silt loam; weak fine granular structure; very friable, nonsticky, nonplastic; common very fine, fine, medium and coarse roots; strongly acid, pH 5.5; clear smooth boundary.
Ab--6 to 11 inches (14 to 28 cm) very dark brown (10YR 2/2) silt loam; weak fine subangular blocky structure; very friable, nonsticky, nonplastic; common very fine and fine roots, and few medium and coarse roots;; strongly acid, pH 5.6; clear smooth boundary.
Bg--11 to 22 inches (28 to 56 cm) dark grayish brown (2.5Y 4/2) silt loam; massive; friable, nonsticky, nonplastic; common very fine and fine roots, and few medium and coarse roots; 5 percent fine strong brown (7.5YR 4/6) redox concentrations; moderately acid, pH 5.8; abrupt smooth boundary.
Ab--22 to 24 inches (56 to 61 cm) very dark grayish brown (2.5Y 3/2) silt loam; weak fine subangular blocky structure; very friable, nonsticky, nonplastic; common very fine and fine roots, and few medium roots and coarse roots; moderately acid, pH 5.8; abrupt smooth boundary.
C--24 to 32 inches (61 to 82 cm) light olive brown (2.5Y 5/4) silt loam; massive; friable, nonsticky, nonplastic; common very fine and fine roots, few medium and coarse roots; moderately acid, pH 5.8; gradual smooth boundary.
Cg--32 to 59 inches (82 to 150 cm) dark grayish brown (2.5Y 4/2) cobbly silt loam; massive; friable, nonsticky, nonplastic; few very fine, fine, medium, and coarse roots; 30 percent coarse dark yellowish brown (10YR 4/6) redox concentrations; moderately acid, pH 5.8.
TYPE LOCATION: Western Interior Rivers Soil Survey Area, Alaska; Ahklun Mountains; UTM north 6778655 and UTM east 458581, zone 4.
RANGE IN CHARACTERISTICS:
Soil moisture regime: Aquic
Mean annual soil temperature: 32 to 34 degrees F
Thickness of organic materials: 2 to 6 inches
O horizons:
Matrix color: hue 10YR, value 2 to 4, chroma 1 to 3
Texture: peat or mucky peat
Reaction Class: very strongly acid to slightly acid
A horizons (where present):
Matrix color: hue 2.5Y or 10YR, value 2 to 4, chroma 2 or 3
Texture: silt loam or mucky silt
Reaction Class: strongly acid to moderately acid
B horizons
Matrix color: hue 5Y, 2.5Y, or 10YR; value 4; chroma 1 or 2
Texture: silt loam or silt
Reaction Class: strongly acid to slightly acid
C horizons:
Matrix color: hue 5Y, 2.5Y, or 10YR; value 4 or 5; chroma 2 to 4
Texture: silt loam or silt
Reaction Class: moderately acid to slightly acid
COMPETING SERIES: These are no series in this family. When a series is established, this series placeholder will be dropped (see REMARKS).
GEOGRAPHIC SETTING:
Parent material: loess and alluvium
Landform: toeslopes of hills, and floodplains
Slope: 0 to 9 percent
Mean annual temperature: 28 to 30 degrees F.
Mean annual precipitation: 15 to 18 inches
GEOGRAPHICALLY ASSOCIATED SOILS: These include Typic Cryaquents and Aquic Cryofluvents on similar landforms.
DRAINAGE AND PERMEABILITY: Very poorly to poorly drained. Low to medium runoff. Permeability is moderate.
USE AND VEGETATION: Used for subsistence and wildlife habitat. The native vegetation is typical of Boreal scrub.
DISTRIBUTION AND EXTENT: MLRA 237 Ahklun Mountains and MLRA 230 - Yukon-Kuskokwim Highlands, Alaska. The soil is extensive.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES PROPOSED: The Western Interior Rivers Area, Alaska, 2007
REMARKS: This series is set-up as a placeholder to allow the use of a short family name. The range in characteristics is broader than a typical series and may even encompass the full range of the family. There are currently no series designated in this soil family.
Diagnostic features and horizons recognized in this profile include:
Mineral horizons: from 2 to 59 inches.
Temperature regime: Cryic
Moisture regime: Aquic
Irregular carbon decrease: 2 to 59 inches
Redox features: 11 to 59 inches
National Cooperative Soil Survey
U.S.A.