LOCATION CHICHANTNA              AK

Established Series
KMO-JPM
02/2022

CHICHANTNA SERIES

The Chichantna series consists of very deep, very poorly drained organic soils formed in peat materials interlayered with strat of ash-influenced loess. Chichantna soils are in depressional areas on upland till plains. Slopes range from 0 to 8 percent. The mean annual temperature is about 32 degrees F., and the average annual precipitation is about 26 inches.

TAXONOMIC CLASS: Euic Fluvaquentic Cryosaprists

TYPICAL PEDON: Chichantna peat - on a 4 percent slope under bog vegetation. (All colors are for moist soil)

Oi-- 0 to 6 inches; dark reddish brown (5YR 2.5/2) slightly decomposed peat, reddish brown (5YR 3/2) squeezed; about 85 percent fibers, less than 75 percent rubbed; few fine and medium sedge and shrub roots; strongly acid; gradual wavy boundary. (3 to 8 inches thick)

Oe--6 to 15 inches; dark reddish brown (5YR 3/2) moderately decomposed peat; dark reddish brown (5YR 3/3) squeezed; about 75percent fibers less than 40 percent rubbed; few fine root shrubs; medium acid; abrupt smooth boundary. (0 to 9 inches thick)

C--15 to 16 inches; light olive brown (2.5Y 5/4) fine sandy loam; massive; friable; medium acid; abrupt smooth boundary.

Oa1--16 to 28 inches; dark reddish brown (5YR 3/2) muck; reddish brown (5YR 3/3) squeezed; about 30 percent fibers, less than 15 percent rubbed; medium acid; abrupt smooth boundary. (0 to 12 inches thick)

C'--28 to 35 inches; olive yellow (2.5Y 6/6) loam; massive; friable; medium acid; abrupt smooth boundary. (combined C horizons: 2 to 12 inches thick)

Oa2--35 to 64 inches; dark reddish brown (5YR 3/2) muck; reddish brown (5YR 3/3) squeezed; about 30 percent fibers, less than 10 percent rubbed; medium acid.

TYPE LOCATION: Yentna Area, Alaska, approximately 1500 feet east and 500 feet south of the northwest corner of section 1, T.17N., R.10W., Seward Meridian.

RANGE IN CHARACTERISTICS: Strata of mineral material, including volcanic ash, occur throughout the profile. Combined thickness of the various mineral strata is less than 12 inches. The subsurface tier is dominantly highly decomposed sphagnum moss peat with less than 15 percent fibers after rubbing. Reaction throughout the profile ranges from strongly acid to slightly acid. The pH (0.01M CaCl2) of the organic materials is 4.5 or greater within some part of the control section.

The organic materials have hue from 5YR to 10YR; value moist of 2 or 3; and chroma moist from 1 to 4.

The mineral strata have hue from 10YR to 5Y; value moist from 3 to 6; and chroma moist from 1 to 4.

COMPETING SERIES: These are the Bowstring and Tyonek series in the same family and the Nikolai series. Bowstring soils do not have strata of volcanic ash. Nikolai soils have a mineral layer thicker than 12 inches within the control section. Tyonek soils are formed in decomposing forest and grassland litter.

GEOGRAPHIC SETTING: Chichantna soils are in depressional areas within upland till plains. Slopes range from 0 to 8 percent. The soils formed in peat deposits interlayered with ash-influenced loess. The mean annual temperature ranges from 30 to 34 degrees F. Average annual precipitation ranges from 20 to 30 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Chuit, Kliskon, Puntilla, Starichkof, and Strandline soils. Chuit, Puntilla, and Strandline soils are well drained mineral soils formed in loess mantles overlying glacial till on moraines. Kliskon soils are somewhat poorly drained mineral soils formed in loess overlying glacial till on moraines. Starichkof soils have dominantly hemic organic material within the control section.

DRAINAGE AND PERMEABILITY: Very poorly drained. Moderate permeability. The water table is at or near the surface. USE AND VEGETATION: The native vegetation is mainly mosses and sedges, with scattered bog birch and ericaceous shrubs. Used as wildlife habitat.

DISTRIBUTION AND EXTENT: South-central Alaska. The series is of minor extent.

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

SERIES ESTABLISHED: Yentna Area, Alaska, 1986.

REMARKS: Diagnostic features and horizons recognized in this profile include: sapric material from 16 to 28 and 35 to 64 inches; frigid temperature regime; mineral strata from 15 to 16 inches and from 28 to 35 inches; pH greater than 4.5 (0.01M CaCl2) from 6 to 65 inches.

ADDITIONAL DATA: Laboratory data is available for this soil - NSSL number 79P-2132-2143.

---

National Cooperative Soil Survey
U.S.A.