LOCATION SOUTHRIVER AK
Established Series
MPS/SAS
02/2022
SOUTHRIVER SERIES
Landscape--valleys
Landform--floodplain
Slope--0 to 15 percent
Parent material--loamy alluvium over sandy and gravelly alluvium
Mean annual precipitation--about 445 mm
Mean annual air temperature--about -3 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--typic
TAXONOMIC CLASS: Sandy-skeletal, mixed Typic Haplocryepts
TYPICAL PEDON: Southriver sandy loam on a north northeastern facing convex, linear floodplain on a slope of 1 percent at an elevation of 265 m (The soil was moist throughout the profile when described on June 19, 2018.)
Oa--0 to 5 cm; highly decomposed plant material, grayish brown (10YR 5/2) dry, very dark grayish brown (10YR 3/2) moist; many very fine and fine and common medium roots; slightly acid (pH 6.1); abrupt wavy boundary
Bw--5 to 27 cm; loamy sand, light brownish gray (10YR 6/2) dry, dark grayish brown (10YR 4/2) moist; weak, coarse, subangular blocky structure; nonsticky, nonplastic; many very fine roots and common fine and medium roots; common very fine and few fine irregular pores; 5 percent gravel; slightly acid (pH 6.3); abrupt wavy boundary
2C1--27 to 60 cm; extremely gravelly sand, light brownish gray (2.5Y 6/2) dry, dark grayish brown (2.5Y 4/2) moist; single grain; nonsticky, nonplastic; many very fine roots and common fine roots; 70 percent fine prominent irregular moderately cemented very dusky red (2.5YR 2.5/2) manganese coatings with sharp boundaries on bottom of rock fragments; 10 percent cobbles, 50 percent gravel; neutral (pH 6.8); abrupt wavy boundary
2C2--60 to 150 cm; gravel, light yellowish brown (2.5Y 6/3) dry, olive brown (2.5Y 4/3) moist; single grain; nonsticky, nonplastic; 90 percent fine prominent irregular moderately cemented very dusky red (2.5YR 2.5/2) manganese coatings with sharp boundaries on bottom of rock fragments; 5 percent cobbles, 80 percent gravel; neutral (pH 6.8)
TYPE LOCATION: Nome Census Area, Alaska, latitude 63.5753130, longitude -160.7320580 degrees, datum WGS84 (Coordinates determined with a GPS unit)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--0 to 3 degrees C
Soil moisture control section--dry less than 45 consecutive days in June through October
Thickness of ochric epipedon--2 to 10 cm
Particle Size Control Section:
*Clay--0 to 8 percent
*Total fragments--55 to 85 percent gravels, cobbles
Oa horizon
Thickness--2 to 10 cm
Bw horizon
Hue--7.5YR or 10YR
Value--3 or 4 moist, 5 or 6 dry
Chroma-2 or 3
Fine-earth texture--silt loam, sandy loam
Clay--5 to 15 percent
Sand--15 to 85 percent
Organic carbon--3 to 5 percent
Total rock fragment content--0 to 10 percent gravel
Reaction--5.6 to 6.3
Thickness--15 to 50 cm
2C horizon
Hue--10YR or 2.5Y
Value--3 or 4 moist, 5 or 6 dry
Chroma--2 or 3
Fine-earth texture--coarse sand, sand, loamy sand
Clay--0 to 5 percent
Sand--80 to 100 percent
Organic carbon--1 to 3 percent
Total rock fragment content--55 to 60 percent
Total gravel content--45 to 60 percent
Total cobble content--0 to 10 percent
Reaction--5.9 to 6.9
Thickness--30 to 40 cm
3C horizon
Value--3 or 4 moist, 5 or 6 dry
Chroma--2 or 3
Fine-earth texture--coarse sand, sand
Clay--0 to 5 percent
Sand--90 to 100 percent
Organic carbon--0.1 to .2 percent
Total rock fragment content--65 to 85 percent
Total gravel content--65 to 85 percent
Total cobble content--0 to 10 percent
Reaction--5.8 to 7.0
COMPETING SERIES:
Como--somewhat excessively drained slopes range to 60 percent, no loamy mantle present, stones present throughout the profile, colluvium derived from coarse grained igneous and sedimentary rock; mountain slopes
Donnelly--micaceous loess parent material on surface, stones present throughout the profile, slope ranges to 70 percent; outwash plains, stream terraces, escarpments, and moraines
Pippin--A horizon present, somewhat excessively drained, does not flood; stream terraces
Sinona--A horizon present, pH of A horizon ranges to extremely acid, value of Bw ranges to 4, chroma of Bw ranges to 6, does not flood' stream terraces
GEOGRAPHIC SETTING:
*Elevation--0 to 550 m
*Climate--warm, moist summers; cold, dry winters
*Mean annual precipitation--305 to 585 mm
*Mean annual air temperature-- -5 to -1 degrees C
*Frost-free period--55 to 90 days
GEOGRAPHICALLY ASSOCIATED SOILS:
*
Goldcoast--gelic soil temperature regime, gelic materials, earth hummocks on terraces in valleys
*
Coalminecreek--somewhat poorly drained, coarse-silty particle-size class, floodplains in valleys
*
Quekilok--aquic conditions at soil surface, histic epipedon; depressions on floodplains
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
*Drainage class--well drained
*Flooding--occasional, very brief
*Saturation during normal years--none
*Saturated hydraulic conductivity (Ksat)--very high in the surface organic layer and sandy-skeletal layer, very high to high throughout the loamy mantle
USE AND VEGETATION:
Use--wildlife habitat, recreation, subsistence
Potential native vegetation--Balsam poplar, bluejoint, graminoid, Altai fescue, feltleaf willow, tealeaf willow, arctic raspberry, locoweed, captiate valerian, tall bluebells, fireweed, dwarf fireweed, Barclay's willow, Schreber's big red stem moss, field horsetail, moss, northern bedstraw, anemone
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 30 to 105 cm
*Ochric epipedon--zone from 0 to 5 cm
*Cambic--zone from 5 to 27 cm
*Lithologic discontinuity--zone from 27 to 150 cm
National Cooperative Soil Survey
U.S.A.