LOCATION YASUDA AK
Established Series
JDP/DJM/TJR
02/2022
YASUDA SERIES
Landscape--alluvial plains
Landform--depressions on stream terraces
Slope--0 to 3 percent
Parent material--alluvium
Mean annual precipitation--about 255 mm
Mean annual air temperature--about -6 degrees C
Depth class--very deep
Drainage class--very poorly drained
Soil moisture regime--aquic
Soil temperature regime--cryic
Soil moisture subclass--typic
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, calcareous Typic Halaquepts
TYPICAL PEDON: Yasuda silt loam on a grassland terrace depression with a slope of 1 percent and an elevation of 110 m (The soil was moist throughout when described on August 28, 2015.)
Oe--0 to 7 cm; mucky peat; few very fine, fine and medium roots; strongly alkaline (pH 8.5); clear smooth boundary
Bng1--7 to 28 cm; silt loam; light gray (5Y 7/2) dry, olive gray (5Y 5/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine, fine, and medium roots; few fine and medium pores; 15 percent strong brown (7.5YR 4/6) moist, masses of oxidized iron in matrix and 20 percent gray (N 5/) moist, iron depletions in matrix; strongly effervescent; strongly alkaline (pH 8.9); clear smooth boundary
Bng2--28 to 43 cm; very fine sandy loam; gray (N 6/) dry, dark gray (N 4/) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; few fine and medium pores; 15 percent strong brown (7.5YR 4/6) moist, masses of oxidized iron in matrix; strongly effervescent; strongly alkaline (pH 8.7); clear smooth boundary
Bng3--43 to 150 cm; very fine sandy loam; light gray (N 7/) dry, gray (N 5/) moist; massive; soft, very friable, nonsticky and nonplastic; slightly effervescent; moderately alkaline (pH 8.4)
TYPE LOCATION: Yukon-Koyukuk Census Area, Alaska; latitude 66.3829700 degrees, longitude -147.6571000 degrees, datum WGS84 (coordinates determined with a GPS)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--0.5 to 2.5 degrees C
Depth to redoximorphic features--0 to 25 cm
Other features--exchangeable sodium percentage of 15 or more in 50 percent of the layers between the mineral soil surface and a depth of 50 cm
Oe horizon
Thickness--5 to 15 cm
Reaction--6.5 to 9.0
A horizon (where present)
Hue--10YR, 2.5Y
Value--2 to 5 moist, 4 to 7 dry
Chroma--1 or 2 moist
Fine-earth texture--silt loam, very fine sandy loam, loam
Clay content--0 to 18 percent
Reaction--7.5 to 9.0
Effervescence--slight to violent
Thickness--2 to 15 cm
Bng1, Bng2, and Bng3 horizons
Hue--N, 5Y, 2.5Y
Value--3 to 5 moist, 4 to 7 dry
Chroma--0 to 2 moist
Fine-earth texture--silt loam, very fine sandy loam, silt
Clay content--0 to 18 percent
Reaction--7.5 to 9.0
Effervescence--slight to violent
Combined thickness--120 to 145 cm
COMPETING SERIES:
None
GEOGRAPHIC SETTING:
Elevation--90 to 300 m
Climate--short, warm summers and long, very cold winters
Mean annual precipitation--210 to 310 mm
Mean annual air temperature-- -12 to 0 degrees C
Frost-free period--45 to 97 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Pitka--aquic conditions within 25 cm with occasional ponding; depression edges on similar landforms
Tlozhavun--no aquic conditions within 150 cm; higher positions on similar landforms
Tajittro--aquic conditions within 100 cm; higher positions on similar landforms
Gwichin--aquic conditions within 100 cm with rare flooding; higher positions on similar landforms
Nuntragut--aquic conditions within 100 cm with rare flooding; higher positions on similar landforms
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--very poorly drained
Saturation in normal years--water table top depth between a depth of 0 to 25 cm in June, saturated below a depth of 25 cm throughout the rest of the year
Flooding--none
Ponding--frequent, brief and long
Saturated hydraulic conductivity (Ksat)--high throughout
USE AND VEGETATION:
Use--wildlife habitat, subsistence, recreation
Potential natural vegetation--slimstem reedgrass, foxtail barley, arctic rush, slender wheatgrass, Nuttall's alkaligrass, bluejoint, water sedge, wheat sedge, common yarrow, great burnet, largeleaf avens, marsh felwort, redwool plantain, silvery primrose, northern bog aster
DISTRIBUTION AND EXTENT: Yukon Flats Lowlands, Alaska; MLRA 232; moderate extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA
SERIES ESTABLISHED: Yukon Flats National Wildlife Refuge, Yukon-Koyukuk Census Area, Alaska; 2020
REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 32 to 107 cm
*Ochric epipedon
*Redoximorphic iron concentrations--Bng1 and Bng2 horizons
*Redoximorphic iron depletions with chroma of 2 or less--Bng1 horizon
*Reduced matrix--Bng1, Bng2, Bng3 horizons
*Aquic conditions--Bng1, Bng2, Bng3 horizons
At least one horizon between 20 to 50 cm depth must have less than 8 percent clay, or have an n value of 0.7 or less.
Exchangeable sodium percentage of 15 or more in Bng1 and Bng2 horizons are inferred from reaction over 8.5 and lab data from similar pedons; see user pedon IDs S2014AK290010, S2014AK2903052, and S2015AK290009 in the NCSS database for supporting chemical data.
National Cooperative Soil Survey
U.S.A.