LOCATION TIKIGAK AK
Tentative Series
SAS/CBB
11/2024
TIKIGAK SERIES
Depth class: very deep
Drainage class: well drained
Parent material: loamy colluvium over gravelly loamy residuum weathered from sandstone and shale
Landscape: hills
Landform: hillslopes
Slopes: 8 to 30 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 85 days
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, nonacid, subgelic Typic Haplogelolls
TYPICAL PEDON: Tikigak silt loam in a white spruce woodland on an east facing linear, linear backslope on a slope of 18 percent at an elevation of 311 m (1,020 ft)
Oi--0 to 13 cm (0 to 5 in); slightly decomposed plant material, dark brown (7.5YR 3/3) moist, brown (7.5YR 5/3) dry; nonsmeary; many very fine, fine, and coarse and common medium roots throughout; moderately acid (pH 5.7); abrupt smooth boundary. (4 to 14 cm, 2 to 6 in thick)
AB--13 to 44 cm (5 to 17 in); silt loam, very dark grayish brown (10YR 3/2) moist, grayish brown (10YR 5/2) dry; weak coarse subangular blocky structure; friable, slightly hard, nonsticky, nonplastic; nonsmeary; common very fine and fine roots throughout; very fine tubular pores; 5 percent coarse, faint, irregular dark brown (10YR 3/3) masses of oxidized iron; 3 percent gravel; moderately acid (pH 5.8); abrupt smooth boundary. (25 to 35 cm, 10 to 14 in thick)
2Bw--44 to 82 cm (17 to 32 in); gravelly loam, dark grayish brown (2.5Y 4/2) moist, light brownish gray (2.5Y 6/2) dry; strong medium granular structure; friable, slightly hard, slightly sticky, moderately plastic; nonsmeary; few very fine roots throughout; fine interstitial pores; 25 percent gravel; moderately acid (pH 6.0); clear smooth boundary. (20 to 90 cm, 8 to 35 in thick)
2C--82 to 200 cm (32 to 79 in); very gravelly sandy loam, dark grayish brown (2.5Y 4/2) moist, light brownish gray (2.5Y 6/2) dry; massive; very friable, soft, nonsticky, slightly plastic; nonsmeary; few very fine roots throughout; very fine interstitial pores; 40 percent gravel; slightly acid (pH 6.3). (61 to 151 cm, 24 to 59 in thick)
TYPE LOCATION: Nulato Hills - Continental Divide and Blackburn Hills Soil Survey Area, Alaska; latitude 64 degrees 53 minutes 49.78 seconds north, longitude 160 degrees 5 minutes 59.97 seconds west, datum WGS84, UTM north 7197446.10 and UTM east 447930.71, zone 4W, datum WGS84.
RANGE IN CHARACTERISTICS:
Soil moisture regime: udic
Soil temperature regime: gelic
Mean annual soil temperature: -1 to 0 degrees C. (30 to 32 degrees F.)
Thickness of organic material: 4 to 14 cm (2 to 6 in)
Thickness of mollic epipedon: 25 to 35 cm (10 to 14 in)
Thickness of cambic horizon: 20 to 90 cm (8 to 35 in)
Depth to redoximorphic concentrations: 4 to 14 cm (2 to 6 in)
Depth to lithologic discontinuity: 29 to 49 cm (11 to 19 in)
Oi horizon:
Hue: 7.5YR or 5YR
Value: 2 to 3 moist, 4 to 5 dry
Chroma: 2 to 4
Texture: slightly decomposed plant material
Organic matter: 60 to 90 percent
Reaction class: moderately acid to neutral (pH 5.6 to 7.3)
AB horizon:
Hue: 10YR or 7.5YR
Value: 2 to 3 moist, 4 to 5 dry
Chroma: 1 to 3
Texture: silt loam or silt
Sand: 0 to 25 percent
Silt: 65 to 98 percent
Clay: 2 to 8 percent
Rock fragments: 0 to 5 percent
Organic matter: 2 to 8 percent
Reaction class: moderately acid to neutral (pH 5.6 to 7.3)
2Bw horizon:
Hue: 2.5Y or 10YR
Value: 3 to 4 moist, 4 to 5 dry
Chroma: 2 to 3
Texture: gravelly or very gravelly loam or sandy clay loam
Sand: 25 to 70 percent
Silt: 0 to 50 percent
Clay: 18 to 30 percent
Rock fragments: 15 to 45 percent
Organic matter: 1 to 4 percent
Reaction class: moderately acid to neutral (pH 5.6 to 7.3)
2C horizon:
Hue: 2.5Y or 10YR
Value: 4 to 5 moist, 6 to 7 dry
Chroma: 2 to 3
Texture: gravelly or very gravelly sandy loam or loam
Sand: 30 to 75 percent
Silt: 5 to 50 percent
Clay: 10 to 22 percent
Rock fragments: 20 to 50 percent
Organic matter: 0.4 to 3 percent
Reaction class: slightly acid to neutral (pH 6.1 to 7.3)
Some pedons have both a folistic and a mollic epipedon.
COMPETING SERIES: This is the Egoosikcreek (AK) series.
Egoosikcreek soils have aquic conditions at depths between 5 to 140 cm (2 to 55 in), silty clay loam textures in the cambic horizon, and occur on swales of mountains.
GEOGRAPHIC SETTING:
Elevation: 130 to 400 meters (430 to 1,310 feet)
Parent material: loamy colluvium over gravelly loamy residuum weathered from sandstone and shale
Landform: hillslopes
Slopes: 8 to 30 percent
Mean annual precipitation: 300 to 500 mm (12 to 20 in)
Mean annual air temperature: -6 to -2 degrees C. (21 to 28 degrees F.)
Frost free period: 70 to 85 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ungalik,
Igniq, and Uvluutit soils.
Ungalik soils have a paralithic contact at depths between 150 to 200 cm (60 to 80 in), a cryic temperature regime, and occur on similar landforms on linear, concave backslope positions.
Igniq soils have a folistic epipedon, cryoturbation at depths below 15 cm (6 in), and occur on similar landforms on footslope and backslope positions.
Uvluutit soils have an ochric epipedon, free carbonates at depths between 26 to 119 cm (10 to 47 in), and occur on similar landforms on convex, convex backslopes.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: well drained
Saturated Hydraulic Conductivity: very high in the Oi horizon, moderately high in the AB and 2C horizons, and moderately high to high in the 2Bw horizon
Permeability: rapid to very rapid in the Oi horizon, moderate in the AB horizon, slow to moderately rapid in the 2Bw horizon, and slow to moderate in the 2C horizon
Runoff: medium or high
USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: splendid feather moss, tealeaf willow, bog blueberry, woodland horsetail, black crowberry, Richardson's willow, white spruce, Schreber's big red stem moss, moss, lingonberry, tomentypnum moss, goose neck moss, Richardson's brookfoam, cup lichen, greygreen reindeer lichen, Sitka alder, marsh Labrador tea, cetraria lichen, netleaf willow, red fruit bearberry, Siberian alder, cloudberry, and shortstalk sedge.
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: 38 to 113 cm (15 to 44 in)
Mollic epipedon: 13 to 44 cm (5 to 17 in) (AB horizon)
Cambic horizon: 44 to 82 cm (17 to 32 in) (2Bw horizon)
Redoximorphic concentrations: 13 to 44 cm (5 to 17 in) (AB horizon)
Lithologic discontinuity: 44 to 200 cm (17 to 79 in) (2Bw and 2C horizons)
ADDITIONAL DATA:
User pedon ID: 2022AK180554
National Cooperative Soil Survey
U.S.A.