LOCATION KUSLINA AK
Established Series
Rev. MHC/JPM
05/2022
KUSLINA SERIES
The Kuslina series consists of very poorly or poorly drained soils formed in a thick organic mat overlying a thin loess mantle underlain by stratified loamy alluvium. Kuslina soils are on stream terraces. Permafrost occurs at a depth of 5 to 14 inches below the surface of the mineral soil. Slopes range from 0 to 7 percent. Mean annual temperature is about 26 degrees F. and the mean annual precipitation is about 12 inches.
TAXONOMIC CLASS: Loamy, mixed, superactive, nonacid, subgelic Typic Historthels
TYPICAL PEDON: Kuslina peat--on a 2 percent slope under dwarf black spruce forest at 1000 feet elevation. (When described, the soil was moist in the top 7 inches of the mineral soil and wet below)
Oi--10 inches to 3 inches; brown (7.5YR 4/2) peat consisting of raw fibrous moss, twigs, and root fibers; gradual smooth boundary. (2 to 9 inches thick)
Oe--3 inches to 0; very dark brown (10YR 2/2) mucky peat; partially decomposed moss, twigs, and root fibers; abrupt smooth boundary. ( 2 to 8 inches thick)
A--0 to 4 inches; very dark brown (10YR 2/2) silt loam with lenses of black (10YR 2/1) mucky silt loam; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; many very fine, fine, and medium roots; neutral (pH 7.0); clear smooth boundary. (1 to 5 inches thick)
2C1--4 to 7 inches; very dark grayish brown (2.5Y 3/2) fine sandy loam; weak thin platy structure; friable, slightly sticky and slightly plastic; common very fine, fine, and medium roots; neutral (pH 7.2); clear wavy boundary. (2 to 25 inches thick)
2C2--7 to 11 inches; very dark grayish brown (2.5Y 3/2) very fine sandy loam with thin strata of loamy fine sand and sand; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; few fine roots; neutral (pH 7.2); abrupt smooth boundary. (3 to 18 inches thick)
2Cf--11 to 21 inches; very dark grayish brown (2.5Y 3/2) fine sandy loam with thin strata of sand, fine sand, and loamy sand; occasional gravel; frozen on August 14, 1983.
TYPE LOCATION: Copper River Area, Alaska; 7 miles northwest of Kenny Lake, 300 feet south and 900 feet east of the NW corner of section 3, T.1N., R.2E., Copper River Meridian.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is less than 32 degrees F. The mat of organic material consists of fibrous moss over partially decomposed moss, twigs, and roots 8 to 16 inches thick. Depth to permafrost ranges from 5 to 14 inches below the mineral soil surface two months after the summer solstice. Composite texture of the stratified particle size control section is sandy loam, fine sandy loam or loam. There is less than 18 percent clay and more than 15 percent fine sand or coarser in the control section. The organic mat is strongly or moderately acid and the mineral soil is neutral to moderately alkaline.
The A horizon has moist hue of 7.5YR or 10YR; moist value of 1, 2, 3, or 4; and moist chroma of 1, 2 or 3. Texture is commonly silt loam but ranges to include mucky silt loam, silt or very fine sandy loam. Color stratification is common in this horizon due to variable organic matter content within the loess strata, however, organic matter content does not exceed 12 percent.
The 2C horizons have moist hue of 10YR, 2.5Y, or 5Y; moist value of 3 or 4; and moist chroma of 1 or 2. Textures are stratified and include very fine sandy loam, fine sandy loam, sandy loam, silt loam, sand and loamy fine sand. Dark colors are due to the high concentration of black sand grains. Coarse fragment content is less than 5 percent. Sandy textures and gravelly strata become more common with increasing depth.
COMPETING SERIES: These are the
Copper River, Deborah (T),
Mendeltna,
Saulich,
Tolsona, and
Umiat (T) series. Copper River, Deborah, and Saulich soils have silty textures with less than 15 percent fine sand or coarser. Mendeltna soils have more than 18 percent clay. Tolsona soils are not stratified. Umiat soils have weathered bedrock within the control section.
GEOGRAPHIC SETTING: Kuslina soils formed in a thick organic mat over a thin loess mantle underlain by stratified loamy alluvium on stream terraces. Slopes are 0 to 7 percent.
The climate is subarctic continental with long, cold winters and short, warm summers. Mean annual precipitation ranges from 8 to 17 inches and the mean annual snowfall ranges from 39 to 68 inches. Mean January temperature is minus 10 degrees F., mean July temperature is 56 degrees F., and the mean annual temperature ranges from 23 to 27 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing
Copper River soils, and the
Klutina, and
Nizina soils. Klutina and Nizina soils are well drained and somewhat excessively drained, have thin organic mats, lack permafrost, and are on floodplains and low stream terraces.
DRAINAGE AND PERMEABILITY: Very poorly or poorly drained. Runoff is slow. Permeability is moderately rapid in the organic mat, moderate in the loess mantle and moderately rapid in the mineral soil above the permafrost. Altered drainage occurs where the insulating organic mat is destroyed by fire or clearing. Loss of the organic mat results in lowering of the permafrost level and subsequent lowering of the water table.
USE AND VEGETATION: Dominant native vegetation on Kuslina soils is black spruce and white spruce forest. The successional state of the vegetation in a given area is closely related to the fire history. This soil is used primarily for wildlife habitat.
DISTRIBUTION AND EXTENT: Copper River Basin, Alaska. The series is of moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES ESTABLISHED: Copper River Area, Alaska. 1986.
REMARKS: Diagnostic horizons and features recognized in this pedon: a histic epipedon from 10 to 0 inches; permafrost at 11 inches, and saturated conditions above the permafrost; coarse-loamy particle size from 0 to 14 inches; pH >5.5 (1:1,H20) in the control section. The particle size control section extends from the surface of the mineral soil to 14 inches. The series control section extends from 10 inches above to 10 inches below the permafrost level.
National Cooperative Soil Survey
U.S.A.