LOCATION TSANA                   AK

Established Series
Rev. JPM/DLM
12/2022

TSANA SERIES


The Tsana series consists of well drained soils formed in silty loess over loamy glacial till. Tsana soils are on till plains. Slopes range from 0 to 20 percent. Mean annual temperature is about 26 degrees F. and the average annual precipitation is about 12 inches.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Typic Haplocryepts

TYPICAL PEDON: Tsana silt loam - on a 1 percent slope under white spruce forest at 1500 feet elevation.

Oi--2 inches to 0; peat; undecomposed roots, mosses, and forest litter; abrupt wavy boundary. (1 to 5 inches thick)

A--0 to 2 inches; black (10YR 2/1) moist silt loam, light brownish gray (10YR 6/2) dry; weak very fine subangular blocky structure; loose, nonsticky and nonplastic; many roots of all sizes; neutral (pH 6.8); abrupt wavy boundary. (1 to 8 inches thick)

Bw--2 to 3 inches; brown (10YR 4/3) moist silt loam, light yellowish brown (10YR 6/4) dry; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many roots of all sizes; neutral (pH 7.0); clear wavy boundary. (0 to 3 inches thick)

2C1--3 to 8 inches; dark grayish brown (2.5Y 4/2) moist fine sandy loam, olive (5Y 5/3) dry; moderate thin platy structure parting to moderate very fine subangular blocky; soft, very friable, nonsticky and slightly plastic; common roots of all sizes; neutral (pH 7.0); clear wavy boundary. (3 to 20 inches thick)

2C2--8 to 14 inches; dark grayish brown (2.5Y 4/2) moist sandy loam with pockets about 3 inches in diameter of loamy sand and sand; weak thin platy structure parting to weak very fine subangular blocky; soft, very friable, nonsticky and nonplastic; few roots; neutral (pH 7.0); clear wavy boundary. (5 to 25 inches thick)

2C3--14 to 30 inches; olive gray (5Y 4/2) moist fine sandy loam; weak thick platy structure; soft, very friable, nonsticky and nonplastic; very few roots in the upper few inches; 10 to 15 percent gravel and cobble; slightly alkaline (pH 7.4); gradual wavy boundary. (0 to 18 inches thick)

2C4--30 to 60 inches; olive gray (5Y 4/2) moist fine sandy loam; strong fine and very fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; 10 to 15 percent gravel and cobble; slightly alkaline (pH 7.6).

TYPE LOCATION: Copper River Area, Alaska; 6 miles east of Kenny Lake; about 1000 feet west and 400 feet south of the NE corner of section 7, T.2S., R.4E., Copper River Meridian.

RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 32 to 35 degrees F. Thickness of the loess mantle ranges from 1 to 8 inches. The weighted average particle size of the control section has less than 18 percent clay and more than 15 percent fine sand or coarser.

The A horizon has hue of 10YR or 2.5Y; value moist of 2, 3 or 4; and chroma moist of 1, 2 or 3. Rock fragment content ranges from 0 to 5 percent gravel; Reaction is slightly acid or neutral. The Bw horizon, when present, has hue of 7.5YR, 10YR, or 2.5Y; value moist of 2, 3 or 4; and chroma moist of 2, 3 or 4. Texture is silt loam, silt, fine sandy loam, sandy loam, or loam. Rock fragment content ranges from 0 to 5 percent gravel. Reaction is slightly acid or neutral.

The 2C horizon has hue of 10YR, 2.5Y or 5Y; value moist of 3, 4 or 5; and chroma moist of 1 or 2. Texture is fine sandy loam, sandy loam or loam. Rock fragment content ranges from 0 to 30 percent gravel and cobble. The reaction ranges from neutral to mildly alkaline.

COMPETING SERIES: These are the Progress, Eska, Ganhona, Kalambach, Mine, Sambrito, Southpaw, Steese, and Tebay series. Progress and Ganhona soils have stratified textures. Eska, Kalambach, Southpaw, and Steese soils have solums greater than 8 inches thick. Mine and Sambrito soils have mean annual soil temperatures above 35 degrees F. Tebay soils have mottles in the substratum.

GEOGRAPHIC SETTING: Tsana soils formed in a thin silty loess mantle overlying loamy glacial till on till plains. Slopes range from 0 to 20 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 Klawasi and Tolsona soils. Klawasi soils are on lacustrine terraces and have less than 10 inches of a loess mantle over clayey substratums. Tolsona soils are on similar landforms and are the permafrost counterparts of the Tsana soils. Due to disturbance of the organic mat, the permafrost table and water table have dropped below the control section in the Tsana soils.

DRAINAGE AND PERMEABILITY: Well drained; runoff is slow to rapid; permeability is moderate.

USE AND VEGETATION: Most areas of Tsana soils have native vegetation of white spruce, aspen and willow. The successional state of the vegetation in a given area is closely related to the fire history. Small areas are cleared for hay and pastureland.

DISTRIBUTION AND EXTENT: Copper River Basin. The series is of moderate extent.

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

SERIES ESTABLISHED: Copper River Area, Alaska. 1990.

REMARKS: Diagnostic horizons and features recognized in this pedon include: cryic temperature regime; weighted average particle size of coarse-loamy from 10 to 40 inches; pH > 5.5 (1:1,H2O) in the control section.

The Tolsona series is recognized for those pedons where, due to thickening of the organic mat, the permafrost table and water table have risen into the series control section.


National Cooperative Soil Survey
U.S.A.