LOCATION SANKLUNA                AK

Established Series
Rev. MHC/JPM
02/2022

SANKLUNA SERIES

The Sankluna series consists of very deep well drained soils formed in stratified sandy and silty alluvium. Sankluna soils are on floodplains. Slopes range from 0 to 15 percent. Mean annual temperature is about 26 degrees F., and the average annual precipitation is about 18 inches.

TAXONOMIC CLASS: Sandy, mixed Typic Cryofluvents

TYPICAL PEDON: Sankluna fine sandy loam on a 2 percent slope under bluejoint grass and willow scrub at 2450 feet (747 meters) elevation. (colors are for moist soil)

AC--0 to 11 inches; dark brown (10YR 3/3) moist fine sandy loam; weak fine granular structure; very friable, nonsticky and nonplastic; many very fine and fine roots; slightly acid (pH 6.5); gradual smooth boundary. (4 to 12 inches thick)

C1--11 to 17 inches; dark grayish brown (2.5Y 4/2) moist stratified fine sand and sand; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; many very fine and fine roots; slightly acid (pH 6.4); gradual smooth boundary. (6 to 24 inches thick)

C2--17 to 43 inches; dark grayish brown (2.5Y 4/2) moist stratified fine sand and sand; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; few very fine roots; slightly acid (pH 6.4); clear smooth boundary. (10 to 28 inches thick)

C3--43 to 60 inches; very dark grayish brown (10YR 3/2) and dark grayish brown (2.5Y 4/2) stratified sand through silt with composite texture of sandy loam; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; slightly acid (pH 6.4).


TYPE LOCATION: Gulkana River Area, Alaska; about 12 miles north of Sourdough; the SE1/4 of the SW1/4 of section 20, T.13N., R.3W., Copper River Meridian.

RANGE IN CHARACTERISTICS: The control section is stratified sand, fine sand, fine sandy loam, loamy fine sand, and silt loam. The composite texture is sand or loamy sand with less than 50 percent very fine sand. The soil is slightly acid or neutral. The organic mat ranges from 0 to 1 inch.

The AC horizon has moist hue of 10YR or 2.5Y; moist value of 2 or 3; and moist chroma of 1, 2, or 3. Texture includes fine sandy loam, loamy fine sand, and fine sand. This horizon is finely stratified in many pedons.

The C horizons have moist hue from 10YR and 2.5Y; moist value from 3 or 4; and moist chroma of 2 or 3. Texture is stratified sand, fine sandy loam, and silt loam. Composite texture is loamy sand or sand. Dark colors are due to the high concentration of black sand grains. Occasional pockets and strata of organic materials occur and have hue of 7.5YR or 10YR; chroma moist of 1 or 2. .

COMPETING SERIES: There are no competing soils in this family. Soils in this subgroup include the Salchaket, Susitna and Takotna. All competing soils have composite textures in the particle-size control section that are coarse-loamy. In addition, Salchaket soils contain large quantities of micaceous material. Takotna soils are calcareous within the control section. Susitna soils are very strongly or strongly acid in the upper horizons.

GEOGRAPHIC SETTING: Sankluna soils formed in stratified sandy alluvium flood plain point bars. Slopes range from 0 to 15 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 is 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 Hogan and Kuslina soils. Hogan soils are on terraces and have permafrost at 20 to 40 inches. Kuslina soils are on high terrace positions and have a histic epipedon and permafrost within the profile.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is slow or medium. These soils are subject to flooding.

USE AND VEGETATION: Primary use of these soils is wildlife habitat and recreation. Most areas have native vegetation of bluejoint reedgrass and willow scrub.

DISTRIBUTION AND EXTENT: Copper River Basin, Alaska. The series is of minor extent.

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

SERIES ESTABLISHED: Gulkana River Area, Alaska. 1999.

REMARKS: Diagnostic features and horizons recognized in this pedon include: sandy size from 0 to 60 inches; assumed irregular decrease in organic carbon based on the stratification and flood history; pH more than 5.5
(1:1,HCl) from 0 to 60 inches; cryic temperature regime.

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National Cooperative Soil Survey
U.S.A.