LOCATION SEALOIL AK
Established Series
MPS/SAS/TJR
02/2022
SEALOIL SERIES
Landscape--hills
Landform--hillslopes
Slope--1 to 16 percent
Parent material--herbaceous organic material over loess
Mean annual precipitation--about 500 mm
Mean annual air temperature--about -3 degrees C
Depth class--very deep
Drainage class--somewhat poorly drained
Soil moisture regime--aquic
Soil temperature regime--cryic
Soil moisture subclass--typic
TAXONOMIC CLASS: Fine-loamy, isotic, nonacid Typic Cryaquepts
TYPICAL PEDON: Sealoil silt loam on an east-southeast facing concave, linear backslope of a hill on a slope of 9 percent at an elevation of 252 m (The soil was moist from 0 to 150 cm when described on July 31, 2019.)
Oi--0 to 7 cm; slightly decomposed plant material, light brown (7.5YR 6/4) dry, brown (7.5YR 4/4) moist; many very fine and common fine, medium, and coarse roots; moderately acid (pH 5.6); abrupt smooth boundary
Oa--7 to 21 cm; highly decomposed plant material, dark grayish brown (10YR 4/2) dry, very dark brown (10YR 2/2) moist; many very fine and common fine and medium roots; strongly acid (pH 5.3); abrupt smooth boundary
A--21 to 34 cm; silt loam, gray (10YR 5/1) dry, very dark gray (10YR 3/1) moist; weak fine subangular blocky structure; friable, nonsticky, nonplastic; common very fine and fine roots; strongly acid (pH 5.3); abrupt smooth boundary
C/Bg--34 to 63 cm; silt loam, 60 percent greenish gray (5GY 6/1) and 40 percent light brownish gray (10YR 6/2) dry, 60 percent dark greenish gray (5GY 4/1) and 40 percent dark grayish brown (10YR 4/2) moist; massive, and weak medium subangular blocky; firm, moderately sticky, moderately plastic; common very fine and fine roots; many fine irregular pores; 6 percent medium irregular strong brown (7.5YR 5/8) masses of oxidized iron and 8 percent coarse irregular brown (7.5YR 4/4) masses of oxidized iron; 3 percent gravel; strongly acid (pH 5.5); clear smooth boundary
Cg--63 to 150 cm; loam, greenish gray (5GY 6/1) dry, dark greenish gray (5GY 4/1) moist; massive; very firm, moderately sticky, moderately plastic; 5 percent medium irregular strong brown (7.5YR 5/8) masses of oxidized iron; 2 percent gravel; moderately acid (pH 5.9)
TYPE LOCATION: Nome Census Area, Alaska, latitude 63.6925060 longitude -160.5174210, datum WGS84 (coordinates determined with a GPS unit)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--0 to 3 degrees C
Soil moisture control section--saturated for more than two weeks during the growing season
Thickness of folistic epipedon--15 to 25 cm
Thickness of cambic horizon--25 to 60 cm
Depth to aquic conditions--25 to 50 cm
Depth to redoximorphic features--30 to 50 cm
Particle Size Control Section:
*Clay--18 to 30 percent
*Total fragments--0 to 10 percent gravels
*Sodium fluoride pH--8.4 to 11.6
*Ratio of 1500 kPa water to measured clay--0.6 to 6.0
Oi horizon
Thickness--4 to 12 cm
Oa horizon
Thickness--6 to 22 cm
A horizon
Hue--7.5YR or 10YR
Value--2 to 3 moist, 4 or 5 dry
Chroma-1 to 3
Fine-earth texture--silt, silt loam
Clay--4 to 14 percent
Sand--8 to 40 percent
Organic carbon--5 to 12 percent
Total rock fragment content--0 to 1 percent gravel
Reaction--5.3 to 6.6
Thickness--5 to 20 cm
C/Bg
Hue--10YR or 5GY
Value--4 or 5 moist, 6 or 7 dry
Chroma--1 or 2
Fine-earth texture--silt loam, clay loam, loam
Clay--14 to 30 percent
Sand--10 to 25 percent
Organic carbon--1 to 5 percent
Total rock fragment content--0 to 5 percent gravel
Reaction--5.5 to 6.8
Thickness--15 to 40 cm
Cg horizon
Hue--5Y, 5GY or N
Value--4 or 5 moist, 6 or 7 dry
Chroma--none or 1
Fine-earth texture--loam, silt loam, silty clay loam
Clay--20 to 35 percent
Sand--15 to 35 percent
Organic carbon--1 to 2 percent
Total rock fragment content--0 to 10 percent gravel
Reaction--5.5 to 6.9
Thickness--80 to 105 cm
COMPETING SERIES: none
GEOGRAPHIC SETTING:
*Elevation--100 to 700 m
*Climate--warm, moist summers; cold, dry winters
*Mean annual precipitation--430 to 615 mm
*Mean annual air temperature-- -5 to -1 degrees C
*Frost-free period--55 to 90 days
GEOGRAPHICALLY ASSOCIATED SOILS:
*
Chiroskey--umbric epipedon, no aquic conditions present, well drained, coarse fragments range to 75 percent in lower part of profile; hillslopes
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
*Drainage class--somewhat poorly drained
*Saturation during normal years--saturated at a depth of between 25 and 50 cm for more than two weeks during the growing season
*Saturated hydraulic conductivity (Ksat)--very high in the surface organic layer, high to moderately high throughout the rest of the profile
USE AND VEGETATION:
Use--wildlife habitat, recreation, subsistence
Potential native vegetation--white spruce, tealeaf willow, Barclay's willow, black crowberry, dwarf raspberry, cloudberry, field horsetail, woodland horsetail, water sedge, wideleaf polargrass, purple marshlocks, violet, arctic sweet coltsfoot, bog blueberry, beachhead iris
DISTRIBUTION AND EXTENT: Nulato Hills-Southern Seward Peninsula Highlands, Alaska; MLRA 240; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES ESTABLISHED: Nulato Hills BLM area, Nome Census Area, Alaska; 2021
REMARKS:
Diagnostic horizons and features recognized in this pedon
*Particle-size control section--zone from 46 to 121 cm
*Folistic epipedon--zone from 0 to 21 cm
*Cambic horizon--zone from 21 to 63 cm
*Reduced matrix--zone from 34 to 150 cm
*Redoximorphic iron concentrations--zone from 34 to 150 cm
*Aquic conditions--zone from 34 to 150 cm
________________________________________
National Cooperative Soil Survey
U.S.A.