LOCATION FAIRBANKS               AK

Established Series
Rev. BEK/JPM/DLM
05/2022

FAIRBANKS SERIES

Depth class: very deep
Drainage class: well drained
Parent Material: micaceous loess
Landform: loess mantled hills, mountain footslopes, and outwash plains
Slopes: 0 to 70 percent
Mean annual temperature: about 26 degrees F., -3.3 C.
Mean annual precipitation: is about 13 inches, 330 mm

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

TYPICAL PEDON: Fairbanks silt loam - forested (All colors are for moist soil)

Oi--0 to 1 inch, (0 to 3 cm); slightly decomposed forest litter.

Oe--1 to 3 inches, (3 to 8 cm); dark reddish brown (5YR 2.5/2) partially decomposed organic materials; many fine and coarse roots; mycelia; abrupt smooth boundary.

A--3 to 6 inches, (8 to 15 cm); brown (10YR 4/3) silt loam; weak fine granular structure; very friable; many fine, medium, and coarse roots; moderately acid (pH 5.8); clear wavy boundary. (2 to 4 inches thick);

E--6 to 9 inches, (15 to 23 cm); brown (10YR 5/3) silt loam; pale brown (10YR 6/3) on ped faces; moderate very thin platy structure; very friable; many fine roots; common fine pores; moderately acid (pH 5.8); clear wavy boundary. (2 to 4 inches thick)

Bw--9 to 18 inches, (23 to 46 cm); dark yellowish brown (10YR 4/4) silt loam; yellowish brown (10YR 5/4) on ped faces; moderate very thin platy structure; very friable; discontinuous bands of pale brown (10YR 6/3) and brown (10YR 5/3) silt loam approximately 1/2 inch thick; dark yellowish brown strata approximately 1/4 inch thick; many fine roots; common fine pores; slightly acid (pH 6.3); abrupt wavy boundary. (8 to 15 inches thick)

BC--18 to 29 inches, (46 to 74 cm); dark grayish brown (2.5Y 4/2) silt loam; moderate very thin platy structure; very friable; common fine roots; common fine pores; slightly acid (pH 6.3); gradual wavy boundary. (4 to 11 inches thick)

C1--29 to 43 inches, (74 to 109 cm); olive (5Y 4/3) silt loam; dark yellowish brown (10YR 4/4) common medium distinct mottles; moderate very thin platy structure; very friable; few fine roots; common fine pores; slightly acid (pH 6.3); gradual wavy boundary. (6 to 20 inches thick)

C2--43 to 60 inches, (74 t0 152 cm); olive (5Y 4/3) silt loam; weak medium platy structure; very friable; few fine roots; common fine pores; neutral (pH 7.0).

TYPE LOCATION: Fairbanks Area, Alaska; in the SW 1/4 of the SE 1/4 of section 29., T.1S., R.2W., Fairbanks Meridian.
RANGE IN CHARACTERISTICS:

Organic layer thickness: 1 to 6 inches, 2 to 15 cm
Solum thickness: 16 to 34 inches, 41 to 86 cm
Weighted average particle size of the control section: less than 18 percent clay and less than 15 percent fine sand or coarser with substantial mica content Reaction: moderately acid to neutral throughout the profile.

A horizon:
Matrix color: hue of 7.5YR or 10YR; value of 3 or 4; chroma of 2 to 4
Texture: silt loam or loam

E horizon:
Matrix color: hue of 7.5YR to 2.5Y; value of 3 to 5; chroma of 2 to 4
Texture: silt loam or loam

Bw horizon:
Matrix color: hue of 7.5YR to 2.5Y' value of 3 to 5; chroma of 2 to 4
Texture: silt loam or loam, thin strata of silty clay loam are present in some pedons

C horizon:
Matrix color: hue of 10YR to 5Y; value of 4 to 6; chroma of 2 to 4
Texture: silt loam or loam

COMPETING SERIES: These are the Bodenburg, Fairless, Koyukuk, Nunaniq, and Toghotthele series in the same family. Bodenburg soils do not have substantial mica content in the control section. Fairless soils do not have thin fine textured lamellae in parts of the solum. Koyukuk have sands and gravel in the substratum. Nunaniq soils are presumed to have warmer soil temperatures. Toghotthele soils have calcium carbonate in the substratum.

GEOGRAPHIC SETTING:
Parent Material: micaceous loess
Landform: loess mantled hills, mountain footslopes, and outwash plains
Slopes: 0 to 70 percent
Climate: cold continental
Mean annual temperature: 24 to 28 degrees F., -4.4 to -2.2 C.
Mean annual precipitation: is 12 to 14 inches, 305 to 356 mm

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Steese and Minto soils on hillslopes. Steese soils are on backslopes and shoulders and are moderately deep to bedrock. Minto soils are on toeslope positions and are moderately well drained.

DRAINAGE AND PERMEABILITY: Well drained, low to high runoff, saturated hydraulic conductivity is moderately high to high through the mineral soil

USE AND VEGETATION: Mostly in forest dominated by white spruce, paper birch and quaking aspen. Some areas are cleared and cultivated for vegetables, grasses and grains.

DISTRIBUTION AND EXTENT: MLRA 231 Interior Alaska Highlands. The series is extensive.

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

SERIES ESTABLISHED: Yukon-Tanana Region, Alaska, 1914.

REMARKS: Diagnostic layers and features recognized in this profile include:
Ochric epipedon: 3 to 9 inches, 8 to 23 cm
Cambic horizon: 9 to 18 inches, 23 to 46 cm
Particle size control section: coarse-silty, 10 to 40 inches, 25 to 102 cm
Temperature regime: Cryic

A detailed discussion of Fairbanks soils is given in J.A. DeMent, "The Morphology and Genesis of Subarctic Brown Forest Soils of Central Alaska", PhD Thesis, Cornell University, 1962; 110pp. and appendix.

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National Cooperative Soil Survey
U.S.A.