LOCATION SIKSRIK AK
Established Series
MJS/MPS
12/2024
SIKSRIK SERIES
Depth class: very deep
Drainage class: well drained
Parent material: loess over gravelly loamy colluvium derived from sedimentary rock
Landscape: hills
Landform: hillslopes
Slope: 4 to 25 percent
Mean annual precipitation: about 400 mm (16 in)
Mean annual air temperature: about -4 degrees C. (25 degrees F.)
Frost-free period: 70 to 90 days
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Haplocryepts
TYPICAL PEDON: Siksrik silt in a white spruce woodland with shrub understory community on a south facing footslope with 15 percent slope at an elevation of 297m (945 ft)
Oe--0 to 3 cm (0 to 1 in); moderately decomposed plant material; dark reddish brown (5YR 2.5/2) moist, dark reddish gray (5YR 4/2) dry; many very fine, fine, and few medium roots throughout; slightly acid (pH 6.3); clear wavy boundary. (2 to 12 cm, 1 to 5 in thick)
A1--3 to 7 cm (1 to 3 in); silt; very dark brown (7.5YR 2.5/2) moist, brown (7.5YR 4/2) dry; moderate medium subangular blocky structure; friable, slightly hard, slightly sticky, nonplastic; nonsmeary; many very fine, fine, and few medium roots throughout; many very fine dendritic tubular pores; 10 percent gravel; slightly acid (pH 6.5); clear wavy boundary. (1 to 4 cm, 0.5 to 2 in thick)
A2--7 to 20 cm (3 to 8 in); silt; dark brown (7.5YR 3/2) moist, brown (7.5YR 5/2) dry; moderate medium subangular blocky structure; friable, slightly hard, slightly sticky, nonplastic; nonsmeary; few very fine and fine roots throughout; common very fine irregular pores; 10 percent gravel; neutral (pH 7.1); clear wavy boundary. (3 to 13 cm, 1 to 5 in thick)
2Bw1--20 to 55 cm (8 to 22 in); very gravelly silt loam; light olive brown (2.5Y 5/3) moist, pale yellow (2.5Y 7/3) dry; weak medium subangular blocky structure; friable, slightly hard, slightly sticky, nonplastic; nonsmeary; few very fine roots throughout; common very fine irregular pores; 40 percent gravel; neutral (pH 6.8); clear wavy boundary. (15 to 50 cm, 6 to 20 in thick)
2Bw2--55 to 200 cm (22 to 79 in); very gravelly silt loam; light brownish gray (2.5Y 6/2) moist, pale yellow (2.5Y 8/2) dry; weak medium subangular blocky structure; friable, slightly hard, slightly sticky, nonplastic; nonsmeary; common very fine irregular pores; 50 percent gravel; neutral (pH 7.0).
TYPE LOCATION: Nulato Hills - Continental Divide and Blackburn Hills Soil Survey Area, Alaska; Latitude 64.2232962 and Longitude -160.3467610; UTM North 7122588.62 and UTM East 434656.93; zone 4, datum WGS84.
RANGE IN CHARACTERISTICS:
Soil moisture regime: udic
Soil temperature regime: cryic
Mean annual soil temperature: 0 to 3 degrees C. (32 to 37 degrees F.)
Thickness of organic material: 2 to 12 cm (1 to 5 in)
Thickness of ochric epipedon: 5 to 29 cm (2 to 11 in)
Thickness of cambic horizon: 133 to 180 cm (52 to 71 in)
Oe horizon:
Hue: 2.5YR, 5YR, 7.5YR, 10YR
Value: 2 to 4 moist, 4 to 6 dry
Chroma: 1 to 3
Texture: moderately decomposed material
Organic matter: 60 to 90 percent
Reaction class: moderately acid to neutral (pH 5.6 to 7.3)
A horizons:
Hue: 2.5YR, 7.5YR, 10YR, 2.5Y
Value: 2 to 4 moist, 4 to 6 dry
Chroma: 1 to 2
Texture: silt, silt loam or their gravelly analogues
Sand: 0 to 40 percent
Silt: 50 to 98 percent
Clay: 2 to 10 percent
Rock fragments: 0 to 25 percent
Organic matter: 2 to 8 percent
Reaction class: moderately acid to neutral (pH 5.6 to 7.3)
2Bw1 horizon:
Hue: 10YR, 2.5Y, 5Y
Value: 4 or 5 moist, 6 to 7 dry
Chroma: 1 to 3
Texture: loam, silt loam or their gravelly analogues
Sand: 10 to 52 percent
Silt: 36 to 80 percent
Clay: 3 to 12 percent
Rock fragments: 15 to 50 percent
Organic matter: 0.5 to 3 percent
Reaction class: moderately acid to neutral (pH 5.6 to 7.3)
2Bw2 horizon:
Hue: 10YR, 2.5Y, 5Y
Value: 4 to 6, 6 to 8 dry
Chroma: 2 or 3
Texture: loam, silt loam or their gravelly analogues
Sand: 10 to 52 percent
Silt: 32 to 80 percent
Clay: 3 to 16 percent
Rock fragments: 35 to 59 percent
Organic matter: 0.5 to 3 percent
Reaction class: moderately acid to neutral (pH 5.6 to 7.3)
Some pedons have a lithic or paralithic contact between 150 to 200 cm (60 to 80 in).
COMPETING SERIES: These are the
Aniruk,
Anugi,
Basaltlake, Buthclake,
Nunatak,
Telay,
Tui,
Urgiilik (AK),
Enentah,
Storm (CO),
Targhee (CO, ID, MT),
Garlet,
Kegsprings,
Mountedith,
Nooney (MT), Gnomes (NM),
Cuberant (UT),
Raymond (WY) series.
Aniruk soils have a frost free period range of 70 to 85 days
Anugi soils have a mean annual precipitation range of 300 to 600 mm (12 to 24 in)
Basaltlake soils have buried A horizons and have a mean annual air temperature of -4 degrees C. (25 degrees F.)
Butchlake soils have a mean annual air temperature range of -4 to -2 degrees C. (24 to 28 degrees F.)
Nunatak soils have a lithic contact at depths between 100 to 150 cm (40 to 60 in) and have a mean annual air temperature range of 0 to 9 degrees C. (32 to 48 degrees F.)
Telay soils have a mean annual air temperature of -3 degrees C. (26 degrees F.)
Tui soils have buried A and Bw horizons and have a mean annual precipitation range of 300 to 600 mm (12 to 24 in)
Urgiilik soils have a lithic contact at depths between 50 to 100 cm (20 to 40 in)
Enentah soils lack an organic surface, have an albic horizon, and have a mean annual air temperature range of 2 to 6 degrees C. (36 to 42 degrees F.)
Storm soils have a mean annual air temperature range of -1 to 3 degrees C. (31 to 38 degrees F.)
Targhee soils have a lithic contact at depths between 50 to 100 cm (20 to 40 in), lack an organic surface, and have a mean annual air temperature range of 2 to 4 degrees C. (36 to 39 degrees F.)
Garlet soils have an albic horizon, have secondary carbonates at depths below 80 cm (32 in), have a mean annual air temperature range of 2 to 7 degrees C. (36 to 45 degrees F.)
Kegsprings soils have a mean annual air temperature range of 1 to 4 degrees C. (34 to 39 degrees F.)
Mountedith soils have a mean annual air temperature range of 1 to 4 degrees C. (34 to 39 degrees F.)
Nooney soils have a lithic contact at depths between 100 to 150 cm (40 to 60 in) and have a mean annual air temperature range of 1 to 4 degrees C. (34 to 39 degrees F.)
Gnomes soils have a mean annual air temperature range of 1 to 3 degrees C. (34 to 38 degrees F.)
Cuberant soils have a lithic contact at depths between 50 to 100 cm (20 to 40 in) and have a mean annual air temperature range of 2 to 5 degrees C. (35 to 41 degrees F.)
Raymond soils have a mean annual air temperature range of 0 to 2 degrees C. (32 to 36 degrees F.)
GEOGRAPHIC SETTING:
Elevation: 50 to 325 meters (165 to 1065 feet)
Parent material: loess over gravelly loamy colluvium derived from sedimentary rock
Landform: hillslopes
Slope: 4 to 25 percent
Mean annual precipitation: 300 to 500 mm (12 to 20 in)
Mean annual air temperature: -6 to -1 degrees C. (21 to 30 degrees F.)
Frost free period: 70 to 90 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Amigak,
Ena,
Iksrukkaa,
Stovecreek, Tenmileriver, and
Urgiilik soils.
Amigak soils have aquic conditions starting between 0 to 25 cm (0 to 10 in), have a reduced matrix starting within 65 cm (26 in), have a histic epipedon, have cryoturbation, and occur on similar landforms on backslopes and footslopes
Ena soils have an umbric epipedon, have a coarse-loamy particle size class, have an isotic mineralogy class, and occur on backslopes and mountainflanks
Iksrukkaa soils have a paralithic contact at depths between 50 to 100 cm (20 to 40 in), have a folistic epipedon, lack a cambic horizon, have a pH range of 3.5 to 5.5, and occur on backslopes and shoulders
Stovecreek soils have aquic conditions starting between 0 to 25 cm (0 to 10 in), have a reduced matrix starting within 70 cm (28 in), have an umbric epipedon, have a coarse-loamy particle size class, have an isotic mineralogy class, have a nonacid reaction class, and occur on drainageways
Tenmileriver soils have an umbric epipedon, have andic soil properties, have a medial over loamy-skeletal particle size class, have an acid reaction class, have a gelic soil temperature regime, and occur on footslopes, backslopes, and mountainflanks, lower third
Urgiilik soils have a lithic contact at depths between 50 to 100 cm (20 to 40 in) and occur on backslopes and mountainflanks, center third
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: well drained
Saturated Hydraulic Conductivity: very high in the Oe horizon, moderately high in the A1 and A2 horizons, and moderately high to high in the 2Bw1 and 2Bw2 horizons
Permeability: rapid to very rapid in the Oe horizon, moderate in the A1 and A2 horizons, and moderate to rapid in the 2Bw1 and 2Bw2 horizons
Runoff: medium
USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: black crowberry, splendid feather moss, white spruce, greygreen reindeer lichen, reindeer lichen, Siberian alder, bog blueberry, sphagnum, beauverd spirea, bluejoint, common ladyfern, cup lichen
DISTRIBUTION AND EXTENT: MLRA 240, Nulato Hills-Southern Seward Peninsula Highlands. The series is of moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Wasilla, Alaska
SERIES ESTABLISHED: Nulato Hills - Continental Divide and Blackburn Hills Soil Survey, Alaska, 2024.
REMARKS: Diagnostic features and horizons recognized in this profile include:
Particle-size control section: 28 to 103 cm (11 to 41 in)
Ochric epipedon: 0 to 20 cm (0 to 8 in) (A1 and A2 horizon)
Cambic horizon: 20 to 200 cm (8 to 79 in) (2Bw1 and 2Bw2 horizons)
Lithologic discontinuity: 20 to 200 cm (8 to 79 in) (2Bw1 and 2Bw2 horizons)
ADDITIONAL DATA:
User pedon ID: 2021AK180814
National Cooperative Soil Survey
U.S.A.