LOCATION CHISTOCHINA             AK

Established Series
Rev. MHC/JPM/DLM
02/2022

CHISTOCHINA SERIES


The Chistochina series consists of very deep, somewhat excessively drained soils formed in sandy glacial drift. Chistochina soils are on drumlins, moraines and undulating glacial till plains. Slopes range from 0 to 7 percent. Mean annual temperature is about 26 degrees F., and the average annual precipitation is about 12 inches.

TAXONOMIC CLASS: Sandy, mixed Typic Haplocryepts

TYPICAL PEDON: Chistochina silt loam -- on a 7 percent slope under aspen forest at 2000 feet elevation. When described the soil was moist throughout.

Oi--3 inches to 0; dark reddish brown (5YR 3/3) fibrous roots, moss and twigs; abrupt smooth boundary. (1 to 4 inches thick)

A--0 to 1 inches; dark brown (10YR 3/3) silt loam; moderate medium platy structure; very friable, nonsticky and nonplastic; many roots of all sizes; slightly acid (pH 6.4); clear irregular boundary. (1 to 6 inches thick)

2Bw--1 to 8 inches; brown (7.5YR 4/4) fine sandy loam; moderate medium subangular blocky structure; very friable, nonsticky and nonplastic; common very fine, fine and medium roots; slightly acid (pH 6.4); clear wavy boundary. (2 to 9 inches thick)

3C1--8 to 17 inches; dark brown (10YR 3/3) loamy fine sand with patches of very dark gray (N 3/0); weak medium subangular blocky structure; very friable, nonsticky and nonplastic; few very fine, fine and medium roots; 10 percent subrounded gravel; neutral (pH 7.0); diffuse smooth boundary. (7 to 25 inches thick)

3C2--17 to 31 inches; very dark gray (10YR 3/1) fine sand: single grain; loose, nonsticky and nonplastic; 10 percent subrounded gravel and occasional cobble; neutral (pH 7.0); diffuse irregular boundary. (12 to 23 inches thick)

3C3--31 to 60 inches; very dark gray (10YR 3/1) gravelly fine sand; single grain; loose, nonsticky and nonplastic; 15 percent subrounded gravel and occasional cobble; neutral (pH 7.2).

TYPE LOCATION: Copper River Area, Alaska; 8 miles east of Copper Center; 1900 feet north and 2600 feet east of the SW corner of section 25, T.3N., R.1E., Copper River Meridian.

RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 32 to 35 degrees F. Thickness of the organic mat ranges from 1 to 4 inches. Thickness of the loess cap is 3 to 15 inches. Solum thickness ranges from 4 to 11 inches. Texture in the control section includes sand, loamy sand, and loamy fine sand with a weighted average of less than 50 percent very fine sand. The soil is slightly acid in the solum and neutral to mildly alkaline in the substratum.

The A horizon has moist hue of 7.5YR or 10YR; moist value of 2 or 3; and moist chroma of 1, 2, or 3. Texture is silt loam or fine sandy loam. Coarse fragment content ranges from 0 to 15 percent with 0 to 15 percent gravel and 0 to 10 percent cobble.

The 2Bw horizon has moist hue of 7.5YR or 10YR; moist value and chroma of 3 or 4. Texture includes sandy loam and fine sandy loam. Coarse fragment content ranges from 0 to 15 percent with 0 to 15 percent gravel and 0 to 10 percent cobble.

The 3C horizons have moist hue of 10YR, 2.5Y, 5Y or neutral; moist value of 2, 3, or 4; and moist chroma of 0, 1, or 2. Textures include loamy fine sand, fine sand, and sand. Pockets of fine sandy loam and loam are common. Dark colors are due to the high concentration of black sand grains. Coarse fragment content ranges from 0 to 30 percent with 5 to 20 percent gravel and 0 to 10 percent cobbles.

COMPETING SERIES: These are the Beales and Chistna series. Beales soils have strongly acid substratums. Chistna soils have strongly acid or moderately acid soil reaction in the upper part of the solumn.

GEOGRAPHIC SETTING: Chistochina soils formed in a thin loess mantleover sandy glacial drift on drumlins, moraines, and undulating glacial till plains. Slopes are convex and range from 0 to 7 percent. The climate is subarctic continental with long, cold winters and short, warm winters. 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 include the Tebay, Tolsona and Pippin soils. Tebay soils have loamy textures and are on drumlins and glacial till plains. Tolsona soils are shallow to permafrost, poorly drained, and are in depressions between drumlins and on undulating glacial till plains. Pippin soils are gravelly, somewhat excessively drained soils on esker hillslopes and till plains.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Runoff is slow to medium. Permeability is moderate in the surface horizon, moderately rapid in the subsoil, and rapid in the substratum.

USE AND VEGETATION: Most areas of Chistochina soils have native vegetation of aspen and white spruce. The successional stage of the vegetation is closely related to fire history. This soil is used primarily for wildlife habitat.

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

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

SERIES ESTABLISHED: Copper River Area, Alaska. 1986.

REMARKS: Diagnostic features and horizons recognized in this profile include: a cambic horizon from 1 to 8 inches; sandy particle size from 8 to 60 inches; a cryic temperature regime.


National Cooperative Soil Survey
U.S.A.