LOCATION NINCHUUN                AK

Established Series
Rev. TLP/JBS/DLM
05/2022

NINCHUUN SERIES

Depth class: shallow or moderately deep to permafrost and glacial till
Drainage class: poorly drained
Parent material: loess over glaciofluvial deposits
Landform: moraines
Slopes: 0 to 35 percent
Mean annual precipitation: about 14 inches
Mean annual temperature: about 26 degrees F.

TAXONOMIC CLASS:

TYPICAL PEDON: Ninchuun silt loam - on a slope of 2 percent under black spruce at 1700 feet elevation. (All colors are for moist soil unless noted)

Oe--0 to 6 inches (0 to 15); very dark brown (10YR 2/2) moderately decomposed organic matter; many very fine to coarse roots; strongly acid (pH 5.4); clear smooth boundary. (3 to 8 inches thick)

A--6 to 12 inches (15 to 31 cm); black (10YR 2/1) silt loam; weak very fine granular structure; very friable; nonsticky and slightly plastic; slightly acid (pH 6.2); clear wavy boundary. (4 to 8 inches thick)

Bg/Ajj--12 to 16 inches (31 to 41 cm); very dark gray (10YR 3/1) and very dark brown (10YR 2/2) silt loam; weak very fine granular structure; very friable; nonsticky and slightly plastic; common very fine to fine roots; slightly acid (pH 6.2); clear wavy boundary. (3 to 7 inches thick)

Bjjg--16 to 20 inches (41 to 51 cm); dark reddish gray (2.5YR 3/1) and very dark brown (10YR 2/2) silt loam; weak thin platy structure; very friable; slightly sticky and slightly plastic; few very fine to fine roots; common fine distinct dark yellowish brown (10YR 3/6) redoximorphic concentrations; slightly acid (pH 6.2); abrupt wavy boundary. (3 to 7 inches thick)

Bjjgf--20 to 32 inches (51 to 81 cm); dark reddish gray (2.5YR 4/1) and dark gray (10YR 4/1) permanently frozen silt loam; massive; extremely firm; slightly sticky and slightly plastic when thawed; common medium prominent dark yellowish brown (10YR 3/6) redoximorphic concentrations; slightly acid (pH 6.4). (10 to 16 inches thick)

2Cf--32 to 60 inches (81 to 152 cm); light olive brown (2.5Y 5/4) permanently frozen gravelly sandy loam; massive; 20 percent gravel; common medium prominent dark yellowish brown (10YR 3/6) redoximorphic concentrations; slightly acid (pH 6.5).

TYPE LOCATION: Near the south end of Meadows Road; in the SW 1/4 of the NW 1/4, section 12, T. 135 S., R. 9 E; Mt. Hayes 1:63,360 quad; Fairbanks Meridian; UTM north 7075795 and UTM east 552867, zone 6.

RANGE IN CHARACTERISTICS:

Mean annual soil temperature: about 25 degrees F
Thickness of organic materials: 2 to 8 inches
Depth to frozen soil (July-August): 16 to 33 inches
Depth to glacial till: 23 to 46 inches


O horizon:
Matrix color: hue of 7.5YR or 10YR; value of 2 or 3; chroma of 1 or 3
Texture: slightly or moderately decomposed organic matter
Reaction class: extremely acid to strongly acid

A horizon:
Matrix color: hue of 7.5YR or 10YR; value of 2 or 3; chroma of 1 or 2
Texture: silt loam or mucky silt loam
Reaction class: strongly acid to slightly acid

Bjjg and Bjjgf horizon:
Matrix color: hue of 10YR or 2.5Y; value of 3 to 5; chroma of 1 to 4
Texture: silt loam
Reaction class: moderately acid or slightly acid

2Cf horizon:
Matrix color: chroma 3 or 4
Texture: gravelly fine sandy loam, gravelly sandy loam, or gravelly silt loam
Coarse Fragments: 15 to 30 percent gravel

COMPETING SERIES: These are the Batza, Bradway, Chetlake, Tanana, and Tetlin series. Batza soils lack coarse fragments in the upper 30 inches of the solum. Bradway and Tanana soils have substantial mica content and lack coarse fragments in the control section. Chetlake soils have cobbles and stones. Tanana soils also contain lenses of fine sand or fine sandy loam. Tetlin series soils formed in micaceous loess on bedrock cored hills and lack coarse fragments in the control section.

GEOGRAPHIC SETTING:
Parent material: loess over glaciofluvial deposits
Landform: moraines
Slope: 0 to 35 percent
Mean annual temperature: 24 to 28 degrees F.
Mean annual precipitation: 12 to 16 inches

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Windyridge series. Windyridge series are well drained soils, without permafrost on glacial moraines.

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

USE AND VEGETATION: The native vegetation includes black spruce forest.

DISTRIBUTION AND EXTENT: MLRA 229, Interior Alaska Lowlands, The series is of moderate extent.

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

SERIES ESTABLISHED: Fort Greely Soil Survey, Alaska, 2002

REMARKS: Diagnostic features and horizons recognized in this profile include:
Umbric epipedon: from 0 to 20 inches
Cambic horizon: from 6 to 20 inches
Moisture regime: Aquic
Redoximorphic features: 12 to 32 inches

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National Cooperative Soil Survey
U.S.A.