LOCATION BRIGADIER               AK

Established Series
Rev. DKS/JPM
02/2022

BRIGADIER SERIES

Depth class: shallow to bedrock
Drainage class: well drained
Parent material: silty micaceous loess over colluvium/residuum
Landform: hill and mountain slopes
Slopes: 0 to 70 percent
Mean annual precipitation: about 12 inches
Mean annual temperature: about 26 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, shallow Typic Dystrocryepts

TYPICAL PEDON: Brigadier silt loam - on a slope of 44 percent at 1700 feet elevation under black spruce forest (All colors are for moist soil)

Oe--0 to 6 inches (0 to 16 cm); black (7.5YR 2.5/1) moderately decomposed plant material; many very fine to coarse roots; extremely acid (pH 3.8); clear smooth boundary. (4 to 9 inches (11 to 24 cm) thick)

A--6 to 8 inches (16 to 20 cm); black (7.5YR 2.5/1) silt loam; weak medium granular structure; friable, slightly sticky and slightly plastic; few fine roots; very strongly acid (pH 4.6); abrupt wavy boundary (2 to 9 inches (4 to 23 cm) thick)

2Bw--8 to 20 inches (20 to 50 cm); brown (10YR 4/3) extremely channery sandy loam; structureless; loose; slightly sticky and slightly plastic; few fine roots; 40 percent channers, to percent flagstones, and 20 percent stones; strongly acid (pH 5.4); gradual smooth boundary. (3 to 12 inches (8 to 50 cm) thick)

2Cr--20 to 24 inches (56 to 60 cm); variegated weathered schist bedrock.

TYPE LOCATION: Fort Wainwright Area, Alaska; UTM zone 6, 515720E 7161229N.

RANGE IN CHARACTERISTICS:
Soil moisture regime: udic
Mean annual soil temperature: 33 degrees F
Thickness of organic materials: 4 to 9 inches
Thickness of loess mantle: 2 to 16 inches
Depth to bedrock: 10 to 20 inches from mineral surface
Coarse fragments in control section: 35 to 75v percent (weighted average)
Other: control section contains substantial amounts of mica; coarse fragments are dominantly schist channers

O horizon:
Matrix color: hue of 5YR to 7.5YR; value of 2 to 4; chroma of 1 to 3
Texture: slightly to moderately decomposed plant material
Reaction class: extremely acid to very strongly acid

A horizon:
Matrix color: hue of 7.5YR to 10YR; value of 2 to 4; chroma of 1 to 3
Texture: silt loam or mucky silt loam
Coarse fragments: 0 to 10 percent
Reaction class: extremely acid to strongly acid
Other: AE horizons present in some pedons

2Bw horizon:
Matrix color: value of 3 or 4; chroma of 3 or 4
Texture: silt loam, loam, or sandy loam
Coarse fragments: 35 to 75 percent
Reaction class: strongly acid to moderately acid

2C horizon (when present):
Matrix color: hue of 10YR to 5Y; value of 4 to 6; chroma of 3 to 6
Texture: loam, sandy loam, or loamy coarse sand
Coarse fragments: 50 to 90 percent
Reaction class: strongly acid to moderately acid

COMPETING SERIES: This is the Gilmore series in the same family. Gilmore soils have O horizons that are thinner than 4 inches.

GEOGRAPHIC SETTING:
Parent material: micaceous loess over weathered schist bedrock
Landform: dominantly north facing hill and mountain sidelsopes
Slope: 0 to 70 percent
Mean annual temperature: 23 to 28 degrees F.
Mean annual precipitation: 10 to 15 inches
Climate zone: cold continental

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gilmore, Steese and Ester soils. Gilmore soils are on similar landforms but are warmer due to south aspects. Ester soils are on northfacing backslopes and have permafrost. Steese soils are on southfacing backslopes and are moderately deep to bedrock.

DRAINAGE AND PERMEABILITY: Well drained. Medium to rapid runoff. Moderate permeability in the loamy surface horizons and moderate to moderately rapid in the skeletal substratum.

USE AND VEGETATION: Most forested. The principal tree species is black spruce of non-commercial quality. Used for recreation, military training, water supply, and wildlife habitat.

DISTRIBUTION AND EXTENT: MLRA 176. East-central Alaska. The series is extensive.

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

SERIES ESTABLISHED: Greater Fairbanks Area, Alaska 2002.

REMARKS: Diagnostic features and horizons recognized in this profile include:
Ochric epipedon: 6 to 20 inches
Cambic horizon: 8 to 20 inches
Temperature regime: cryic
Moisture regime: udic
Particle size: weighted average of loamy-skeletal from 16 to 20 inches
Other: paralithic contact at 20 inches

Brigadier soils thaw more slowly in spring than south-facing counterparts. Some pedons retain seasonal frost until mid-July.

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National Cooperative Soil Survey
U.S.A.