LOCATION KUSKOKWIMFAMILY AK
Tentative Series
Rev. JPM
02/2022
KUSKOKWIMFAMILY SERIES
Note: Used as a placeholder series until a series is established under the family class
Depth class: Very deep
Drainage class: somewhat poorly drained
Parent material: loess and alluvium
Landform: toeslopes and footslopes of hills, terraces, and floodplains
Slopes: 0 to 12 percent
Mean annual precipitation: about 16 inches
Mean annual temperature: about 29 degrees F.
TAXONOMIC CLASS: Coarse-silty, mixed, superactive Aquic Haplocryepts
TYPICAL PEDON: Kuskokwimfamily silt loam - on a slope of 1 percent on a terrace under tundra vegetation at 187 feet elevation. (All colors are for moist soil unless noted)
Oi--0 to 2 inches, (0 to 6 cm); very dark brown (7.5YR 2.5/3) slightly decomposed organic matter; common very fine and fine, and few medium and coarse roots; moderately acid, pH 6.0; abrupt smooth boundary.
A--2 to 6 inches, (6 to 14 cm); very dark brown (10YR 2/2) silt loam; weak fine granular structure; friable, nonsticky, nonplastic; common very fine and fine and few coarse roots; strongly acid, pH 5.5; clear smooth boundary.
Bw--6 to 24 inches, (14 to 60 cm); olive brown (2.5Y 4/4) silt loam; moderate medium granular structure; firm, nonsticky, nonplastic; common very fine and fine roots, and few medium and coarse roots; 10 percent fine grayish brown (2.5Y 5/2) gley; slightly acid, pH 6.5; gradual smooth boundary.
C1--24 to 69 inches, (60 to 175 cm); brown (10YR 4/3) silt loam; weak medium platy structure; firm, nonsticky, nonplastic; few very fine, fine, medium and coarse roots; 20 percent fine gray (10YR 5/1) gley and 25 percent fine strong brown (7.5YR 4/6) redox concentrations; slightly acid, pH 6.5; clear smooth boundary.
C2--69 to 79 inches, (175 to 200 cm); brown (10YR 4/3) stratified very fine sandy loam to silt loam; weak medium platy structure; friable, nonsticky, nonplastic; few very fine, fine, medium and coarse roots; 20 percent fine gray (10YR 5/1) gley and 25 percent fine strong brown (7.5YR 4/6) redox concentrations; slightly acid, pH 6.5.
TYPE LOCATION: Western Interior Rivers Soil Survey Area, Alaska; Red Devil area along south bank of river; UTM north 6853210 and UTM east 578541, zone 4.
RANGE IN CHARACTERISTICS:
Soil moisture regime: Udic
Mean annual soil temperature: 32 to 34 degrees F
Thickness of organic materials: 2 to 6 inches
Depth to coarse fragments: below 50 inches
O horizons:
Matrix color: hue 10YR, 7.5YR, or 5YR, value 2 or 3, chroma 1 to 3
Texture: slightly or moderately decomposed organic matter
Reaction Class: extremely acid to moderately acid
A horizons:
Matrix color: hue 10YR or 7.5YR; value 2 to 5; chroma 2 or 3
Texture: silt loam or very fine sandy loam
Reaction Class: very strongly acid or strongly acid
B horizons:
Matrix color: hue 2.5Y, 10YR, or 7.5YR; value 2 to 5; chroma 1 to 4
Texture: silt loam or very fine sandy loam
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 very fine sandy loam
Reaction Class: strongly acid to slightly acid
2C horizons (when present)
Texture: very gravelly sand, very gravelly coarse sand
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 and footslopes of hills, terraces, and floodplains
Slope: 0 to 12 percent
Mean annual temperature: 28 to 30 degrees F.
Mean annual precipitation: 15 to 18 inches
GEOGRAPHICALLY ASSOCIATED SOILS: These include Typic Histoturbels and Typic Cryofluvents on similar landforms.
DRAINAGE AND PERMEABILITY: Somewhat 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, woodland, and forestland.
DISTRIBUTION AND EXTENT: MLRA 229 - Interior Alaska Lowlands; MLRA 230 - Yukon-Kuskokwim Highlands; and MLRA 238- Yukon-Kuskokwim Coastal Plain, 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 79 inches.
Temperature regime: Cryic
Moisture regime: Udic
Cambic horizon: 6 to 24 inches
Redox features: 24 to 79 inches
National Cooperative Soil Survey
U.S.A.