LOCATION TETLIN                  AK

Established Series
Rev. DKS/JPM
02/2022

TETLIN SERIES

Depth class: shallow to deep over permafrost
Drainage class: poorly drained
Parent material: micaceous loess or colluvium derived from loess
Landform: bedrock-cored hillslopes
Slope: 3 to 50 percent
Mean annual precipitation: 9 to 15 inches
Mean annual temperature: 21 to 28 degrees F.

TAXONOMIC CLASS:

TYPICAL PEDON: Tetlin peaty silt loam - on a 30 percent slope under white spruce forest at 1500 feet elevation. (All colors are for moist soil)

Oi--0 to 6 inches; dark brown (7.5YR 3/2) slightly decomposed plant material; extremely acid (pH 4.4); clear wavy boundary. (1 to 8 inches thick)

O/E--6 to 7 inches; dark brown (7.5YR 3/2) slightly decomposed plant material and light brownish gray (10YR 6/2) silt loam; single grain; loose, nonsticky and nonplastic; many very fine to coarse roots; extremely acid (pH 4.2); clear wavy boundary.

Bw--7 to 23 inches; dark brown (10YR 3/3) silt loam; weak coarse subangular blocky structure; friable, nonsticky and slightly plastic; few very fine to fine roots; moderately acid (pH 5.8); abrupt smooth boundary.

Bgf--23 to 60 inches; olive brown (2.5Y 4/4), perennially frozen silt loam; massive, parting to weak medium platy structure; very hard; nonsticky and slightly plastic (when thawed): common large distinct dark grayish brown (2.5Y 4/2) redoximorphic depletions; slightly acid (pH 6.4).

TYPE LOCATION: Gerstle River Area, Alaska; about 30 miles east southeast of Delta Junction; SW 1/4 of the SW 1/4 of section 36, T.12S., R.15E.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: less than 32 degrees F
Particle size control section: less than 18 percent clay and less than 15 percent fine sands or coarser
Depth to permafrost: 10 to 60 inches below the soil surface
Coarse fragments: weathered rock fragments may occur below 40 inches

The O horizon is slightly decomposed plant material
Reaction class: extremely acid to slightly acid.

A horizon: (where present)
Matrix color: hue of 7.5YR or 10YR; value of 2 or 3; chroma of 1 or 2
Texture: silt loam, mucky silt loam or peaty silt loam
Reaction class: strongly acid or moderately acid

Bw horizon:
Matrix color: value of 3 to 5, chroma of 3 or 4
Texture: silt loam or very fine sandy loam
Reaction class: strongly acid to mildly alkaline

Bg and Bgf horizons:
Matrix color: hue of 10YR to 5Y, value of 3 to 5; chroma of 1 to 4
Redoximorphic features are common
Texture: silt loam or very fine sandy loam
Thin buried A horizons: present in some pedons
Reaction class: moderately acid to slightly alkaline

COMPETING SERIES: These are the Batza, Bradway, Chetlake, Ninchuun, and Tanana series of the same family. Batza, Chetlake, and Ninchuun soils do not have micaceous influence. Bradway and Tanana soils have lenses of fine sand or fine sandy loam.

GEOGRAPHIC SETTING:
Parent material: micaceous loess or colluvium derived from loess
Landform: bedrock-cored hillslopes
Slope: 3 to 50 percent
Climate: is boreal continental, with short, warm summers and long, cold winters Mean annual precipitation: 9 to 15 inches, approximately one third of which falls as snow
Mean annual temperature: 21 to 28 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Steese soils and Gilmore soils. The Steese and Gilmore soils lack permafrost and occur on ridge crests and south-facing slopes of the bedrock hills.

DRAINAGE AND PERMEABILITY: Poorly drained. Medium to very rapid runoff. Saturated hydraulic conductivity is moderately high above the permafrost and very low in the permafrost.

USE AND VEGETATION: Tetlin soils support forests of white spruce and black spruce, often with an alder understory. They are used for wildlife habitat and watershed management.

DISTRIBUTION AND EXTENT: MLRA 231, Interior Alaska Highlands. The series is of limited extent.

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

SERIES ESTABLISHED: Gerstle River Area, Alaska, 1995.

REMARKS: Diagnostic features recognized in this profile include:
Permafrost: 23 inches with aquic conditions above
Cambic horizon: 7 to 23 inches
Temperature regime: pergelic
Particle size control section: coarse-loamy from 10 to 40 inches
Moisture regime: aquic

Saturated soil is present above the permafrost to within 10 inches of the surface in mid-summer.

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National Cooperative Soil Survey
U.S.A.