LOCATION JOKINAUGH AK
Established Series
JDP/DJM/TJR
05/2022
JOKINAUGH SERIES
Landscape--alluvial plains
Landform--depressions on flood plains
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--poorly drained
Soil moisture regime--aquic
Soil temperature regime--cryic
Soil moisture subclass--typic
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, nonacid Typic Cryaquents
TYPICAL PEDON: Jokinaugh silt loam on a mixed shrub and grassland flood plain depression with a slope of 0 percent and an elevation of 100 m (The soil was moist throughout when described on July 17, 2008.)
Oe--0 to 5 cm; mucky peat; many fine and medium roots, and few coarse roots; neutral (pH 6.7); abrupt smooth boundary
A--5 to 7 cm; silt loam; grayish brown (10YR 5/2) dry, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium roots; common fine and medium pores; neutral (pH 6.6); abrupt smooth boundary
Cg1--7 to 80 cm; silt loam; light gray (2.5Y 7/1) dry, gray (2.5Y 5/1) moist; strong fine angular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots, and common medium roots; few fine and medium pores; 7 percent strong brown (7.5YR 4/6) moist, masses of oxidized iron; noneffervescent; neutral (pH 7.3); diffuse smooth boundary
Cg2--80 to 130 cm; silt loam; 70 percent gray (2.5Y 6/1) dry, dark gray (2.5Y 4/1) moist, 30 percent light olive brown (2.5Y 5/3) dry, dark olive brown (2.5Y 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine pores; 5 percent strong brown (7.5YR 4/6) moist, masses of oxidized iron and 5 percent dark reddish brown (5YR 3/3) moist, masses of oxidized iron; noneffervescent; neutral (pH 7.1); clear smooth boundary
Cg3--130 to 150 cm; silt loam; 70 percent grayish brown (2.5Y 5/2) dry, very dark grayish brown (2.5Y 3/2) moist, 30 percent light olive brown (2.5Y 5/3) dry, dark olive brown (2.5Y 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; few fine pores; slightly effervescent; slightly alkaline (pH 7.5)
TYPE LOCATION: Yukon-Koyukuk Census Area, Alaska; latitude 66.0086111 degrees, longitude -149.0844444 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
Oe horizon
Thickness--2 to 10 cm
Reaction--5.0 to 7.0
Oa horizon (where present)
Thickness--2 to 10 cm
Reaction--5.0 to 7.0
A horizon
Hue--10YR, 2.5Y
Value--2 or 3 moist, 4 or 5 dry
Chroma--1 or 2 moist
Fine-earth texture--silt loam, very fine sandy loam, silt
Clay content--2 to 18 percent
Reaction--6.0 to 8.0
Effervescence--none to slight
Thickness--1 to 12 cm
Bg horizon (where present)
Hue--10YR, 2.5Y, 5Y
Value--3 to 5 moist, 5 to 7 dry
Chroma--1 or 2 moist
Fine-earth texture--silt loam, very fine sandy loam, silt
Clay content--2 to 18 percent
Reaction--6.5 to 8.0
Effervescence--none to strong
Thickness--10 to 30 cm
Cg1 and Cg2 horizons
Value--2 to 5 moist, 4 to 7 dry
Chroma--1 or 2 moist
Fine-earth texture--silt loam, very fine sandy loam, silt
Clay content--2 to 18 percent
Reaction--6.5 to 8.0
Effervescence--none to strong
Combined thickness--120 to 145 cm
COMPETING SERIES:
Peede--these soils contain buried surface horizons and visible mica in the solumn
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:
Chetlechak--aquic conditions within 50 cm with frequent ponding; depression edges on similar landforms
Theodore--aquic conditions within 100 cm; similar landforms, proximal to major rivers
Kingslough--no aquic conditions within 150 cm; permafrost within 100 cm; higher positions on similar landforms
Tanjoga--aquic conditions within 25 cm with frequent ponding; adjacent floodplains of low energy rivers
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained
Saturation in normal years--water table top depth between a depth of 0 to 50 cm in May and June during flooding and ponding events; saturated between depths of 50 to 75 cm in July, and saturated below a depth of 75 cm throughout the rest of the year
Flooding--occasional, brief
Ponding--frequent, long
Saturated hydraulic conductivity (Ksat)--moderately high or high throughout
USE AND VEGETATION:
Use--wildlife habitat, subsistence, recreation
Potential natural vegetation--bluejoint, Northwest Territory sedge, wheat sedge, largeleaf avens, starwort, fireweed, field horsetail, threepetal bedstraw, wild mint
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 30 to 105 cm
*Ochric epipedon
*Reduced matrix--Cg1, Cg2, and Cg3 horizons
*Redoximorphic iron concentrations--Cg1 and Cg2 horizons
*Aquic conditions--Cg1, Cg2, and Cg3 horizons
National Cooperative Soil Survey
U.S.A.