LOCATION NIKOLAI                 AK

Established Series
Rev. RBH/SR/DLM
05/2022

NIKOLAI SERIES

Depth class: very deep
Drainage class, poorly or somewhat poorly drained
Parent material: muck over loamy till over sandy and gravelly glaciofluvial deposits
Landform: depressions on till plains and coastal plains
Slopes: 0 to 12 percent
Mean annual precipitation: 18 to 24 inches.
Mean annual temperature: about 33 degrees F.

TAXONOMIC CLASS: Loamy, mixed, dysic Terric Cryosaprists

TYPICAL PEDON: Nikolai peat -- undisturbed (All colors are for moist soil)

Oi--0 to 2 inches; brown (7.5YR 4/2) mucky peat; many very fine, fine, and medium roots; extremely acid (pH 4.2); abrupt smooth boundary.

Oa--2 to 32 inches; dark reddish brown (5YR 2.5/2) muck; many very fine, fine, and medium roots; extremely acid (pH 4.3); abrupt smooth boundary. (Combined thickness of the O horizons is 12 to 35 inches thick)

2Cg1--32 to 41 inches; dark gray (2.5Y 4/1) silt loam; massive; firm, nonsticky and nonplastic; few very fine and fine roots; very strongly acid (pH 4.8); clear wavy boundary. (5 to 14 inches thick)

3Cg2--41 to 60 inches; gray (5Y 5/1) loamy sand; single grained; very friable, nonsticky and nonplastic; few very fine roots; strongly acid (pH 5.2).

TYPE LOCATION: Western Kenai Peninsula Area, Alaska; about 2 miles south of the Kenai River; in the SW 1/4 of the NE 1/4, section 29, T. 5 N., R. 11 W.; Kenai B4 NE 1:25,00 quad; Seward Meridian; UTM north 6708155 and UTM east 596465, zone 3.

RANGE IN CHARACTERISTICS:
Thickness of organic material: 12 to 35 inches
Lenses of volcanic ash: may occur anywhere in the profile

O horizons:
Matrix color: has 5YR to 10YR; value of 2 to 4; chroma of 1 to 3
Reaction class: extremely acid or very strongly acid

2Cg horizon:
Matrix color: hue of 10YR to 5Y; value of 2.5 to 5; chroma of 1 or 2
Texture: silt loam, very fine sandy loam, fine sandy loam modified by 0 to 25 percent total coarse fragments; 0 to 20 percent gravel, 0 to 5 percent cobbles
Reaction class: very strongly acid or strongly acid

3Cg horizon:
Matrix color: hue of 10YR to 5Y; value of 2.5 to 5; chroma of 1 or 2
Texture: loamy sand, sand modified by 0 to 45 total coarse fragments; 0 to 40 percent gravel, 0to 5 percent gravel
Reaction class: very strongly acid to moderately acid

COMPETING SERIES: There are no competing series in this classification.

GEOGRAPHIC SETTING:
Drainage class, poorly or somewhat poorly drained
Parent material: muck over loamy till over sandy and gravelly glaciofluvial deposits
Landform: depressions on till plains and coastal plains
Slopes: 0 to 12 percent
Climate: maritime with cool summers and long moderately cold winters
Mean annual temperature: about 33 degrees F.
Mean annual precipitation: 18 to 24 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cohoe, Island, and Kalifonsky soils. Cohoe and Island soils are well drained mineral soils of uplands. Kalifonsky soils are somewhat poorly drained soils of bog border positions.

DRAINAGE AND PERMEABILITY: Poorly drained, very high runoff. Saturated hydraulic conductivity is moderately high in the muck layer, high in the loamy layer, and high to very high is the sandy layer. The water table is near the surface much of the time, but commonly drops several feet in late summer.

USE AND VEGETATION: A few areas are used for gardens or forage crops. Mostly the soils are in native vegetation consisting of tall grass, dominantly bluejoint, and associated forbs and shrubs. In places, there is a forest dominated by white spruce and paper birch with varying amounts of willows and balsam poplar.

DISTRIBUTION AND EXTENT: MLRA 224, Cook Inlet Lowlands, South-central Alaska. The series is of small extent.

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

SERIES ESTABLISHED: Kenai - Kasilof Area, Alaska. 1960.

REMARKS: Diagnostic features and horizon in this profile include:
Muck soil texture: from 2 to 32 inches
Loamy and sandy textures: from 32 to 60 inches
Temperature regime: cryic
Reaction class: less than 5.0 in (1:1 H2O) in the control section

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National Cooperative Soil Survey
U.S.A.