LOCATION GERSTLE                 AK

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

GERSTLE SERIES

Depth class: very deep
Drainage class: well drained
Parent material: stratified silty and sandy alluvium
Landform: alluvial plains, stream terraces, or alluvial fans
Slope: 0 to 3 percent
Mean annual temperature: 21 to 28 degrees F., -5 to -2.2 C.
Mean annual precipitation: 9 to 13 inches, 227 to 330 mm

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Aquic Haplocryepts

TYPICAL PEDON: Gerstle silt loam - on a 0 percent slope under black spruce forest at 1150 feet elevation. (All colors are for moist soil).

Oi--0 to 8 inches (0 to 19 cm); dark brown (7.5YR 3/2) peat consisting of slightly decomposed organic matter; many very fine to coarse roots; extremely acid (pH 4.2); clear smooth boundary. (2 to 8 inches thick)

AE--8 to 10 inches (19 to 25 cm); black (10YR 2/1) and brown (10YR 5/3) silt loam; weak medium subangular blocky structure; friable, nonsticky and slightly plastic; few very fine to fine roots; strongly acid (pH 5.2); abrupt wavy boundary. (1 to 5 inches thick)

Bw--10 to 43 inches (25 to 109 cm); brown (10YR 4/3) and brown (7.5YR 4/4) silt loam stratified with loamy fine sand; weak medium subangular blocky structure; very friable, nonsticky and nonplastic; few very fine to fine roots; common, large, prominent, grayish brown (2.5Y 5/2) redoximorphic depletions; moderately acid (pH 5.6); gradual smooth boundary.

BC--43 to 60 inches (109 to 152 cm); dark grayish brown (2.5Y 4/2) and dark yellowish brown (10YR 4/4) silt loam; massive; very friable; nonsticky and nonplastic; moderately acid (pH 6.0).

TYPE LOCATION: Gerstle River Area, Alaska; about 20 miles east-southeast of Delta Junction; SW 1/4 of the SW 1/4 of section 6, T.11S., R.14E.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 32 to 35 degrees F
O horizon:
Reaction class: extremely acid to strongly acid

AE or A horizons:
Matrix color: hue of 7.5YR or 10YR, value of 3 to 5, chroma of 2 to 4
Texture: silt loam or very fine sandy loam
Reaction class: strongly acid to neutral

Bw horizon:
Matrix color: hue of 7.5YR or 10YR, value of 3 to 5, chroma of 2 to 4
Redoximorphic features: hue of 2.5Y or 10YR, value of 3 to 5
Texture: silt loam or very fine sandy loam, may have strata of fine sandy loam, loam, fine sand, or sand, thin buried A or O horizons occur in some pedons
Reaction class: strongly acid to neutral

BC horizon:
Matrix color: hue of 10YR or 2.5Y, value of 3 to 5, chroma of 2 to 4
Redoximorphic features: hue of 2.5Y or 10YR, value from 3 to 5
Texture: silt loam with strata of fine sandy loam, loam, fine sand, loamy fine sand, or sand
Reaction class: strongly acid to neutral

C horizon or 2C horizon: (where present):
Matrix: Hue of 2.5Y or 10YR, value 3 to 5, chroma 2 to 4, or variegated
Texture: sand, fine sandy loam, sandy loam, loamy sand, stratified sand to fine sandy loam
Reaction class: strongly acid to neutral
Coarse fragments: 0 to 10 percent gravels.
Reaction class: strongly acid to neutral

COMPETING SERIES: This are the Audrey, Kusdry, Manchu, and Stamp (ID) soils. Audrey soils have rock fragments in the control section. Kusdry soils have saturated conditions below 36 inches. Manchu soils are moderately deep to weathered bedrock. Stamp soils have a mean annual soil temperature greater than 36 degrees F.

GEOGRAPHIC SETTING:
Parent material: stratified silty and sandy alluvium
Landform: alluvial plains, stream terraces, or alluvial fans
Slope: 0 to 3 percent
Climate: boreal continental with short, warm summers and long, cold winters
Mean annual temperature: 21 to 28 degrees F., -5 to -2.2 C.
Mean annual precipitation: 9 to 13 inches, 227 to 330 mm approximately one third of which falls as snow.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arrow, Moosehead, Jarvis, Salchaket, Tanacross and Beales soils. Arrow and Moosehead soils are on the alluvial plain where the loamy mantle over sand and gravel is thinner. Jarvis and Salchaket soils are in flooded areas between Gerstle soils and rivers. Tanacross soils occur where a thick surface organic horizon and permafrost have developed. Beales soils are on sandy hills or sandy plains.

DRAINAGE AND PERMEABILITY: Well drained. Slow runoff. Saturated hydraulic conductive is moderately high or high in the solum and high or very high in the substratum.

USE AND VEGETATION: Gerstle soils support forests dominated by black spruce, white spruce, and paper birch. Cleared areas are used for small grains, forages, and vegetables.

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

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

SERIES ESTABLISHED: Gerstle River Area, Alaska, 1995.

REMARKS: Diagnostic horizons and features recognized in this profile include: Cambic horizon: 2 to 35 inches, 5 to 89 cm
Temperature regime: cryic
Moisture regime: udic
Redoximorphic depletions: within 30 inches, 75 cm. of the mineral surface
Particle size control section: coarse-loamy from 10 to 40 inches, 25 to 102 cm from mineral soil surface.

If undisturbed for a prolonged period, forest succession may lead to the buildup of a thick O horizon and permafrost may become established.
In the spring a perched water table occurs over seasonal frost.

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National Cooperative Soil Survey
U.S.A.