LOCATION NUNANJIAK AK
Tentative Series
SAS/MPS
10/2024
NUNANJIAK SERIES
Depth class: deep to paralithic bedrock
Drainage class: well drained
Parent material: herbaceous organic material over volcanic ash influenced loamy colluvium over gravelly loamy colluvium over gravelly loamy residuum weathered from mudstone
Landscape: mountains, hills
Landform: mountain slopes, hillslopes
Slopes: 20 to 70 percent
Mean annual precipitation: about 450 mm (18 in)
Mean annual air temperature: about -3 degrees C. (27 degrees F.)
Frost-free period: 70 to 90 days
TAXONOMIC CLASS: Medial over loamy-skeletal, mixed over isotic Andic Humicryepts
TYPICAL PEDON: Nunanjiak highly organic silt loam in an alder community on a west facing linear, linear backslope on a slope of 45 percent at an elevation of 450m (1475 ft).
Oe--0 to 7 cm (0 to 3 in); moderately decomposed plant material; very dark brown (7.5YR 2.5/2) broken face moist, brown (7.5YR 4/2) broken face dry: common very fine, fine, medium, coarse, and very coarse roots throughout; extremely acid (pH 4.0; clear wavy boundary. (4 to 10 cm, 2 to 4 in thick)
Oa--7 to 21 cm (3 to 8 in); highly decomposed plant material; black (10YR 2/1) broken face moist, dark gray (10YR 4/1) broken face dry; common very fine, fine, and medium roots throughout; 10 percent channers; extremely acid (pH 3.7), slightly acid (NaF pH 6.5); gradual wavy boundary. (10 to 16 cm, 4 to 6 in thick)
Bw--21 to 35 cm (8 to 14 in); channery highly organic silt loam; dark olive brown (2.5Y 3/3) broken face moist, light olive brown (2.5Y 5/3) broken face dry; weak medium granular structure; very friable, soft, nonsticky, nonplastic, nonsmeary; common very fine, fine, and medium roots throughout; common very fine, fine, and medium tubular pores; 25 percent channers; very strongly acid (pH 5.0), very strongly alkaline (NaF pH 9.3); 6 percent volcanic glass; clear wavy boundary. (8 to 20 cm, 3 to 8 in thick)
A--35 to 46 cm (14 to 18 in); very channery highly organic silt loam; 60 percent very dark brown (10YR 2/2) broken face and 40 percent black (10YR 2/1) broken face moist, 60 percent dark grayish brown (10YR 4/2) broken face and 40 percent dark gray (10YR 4/1) broken face dry; weak fine granular structure; very friable, soft, slightly sticky, nonplastic, nonsmeary; common very fine and fine roots throughout; common very fine, fine, and medium tubular pores; 40 percent channers; very strongly acid (pH 4.9), strongly alkaline (NaF pH 9.0); 15 percent volcanic glass; clear wavy boundary. (5 to 35 cm, 2 to 14 in thick)
Bhs--46 to 67 cm (18 to 26 in); flaggy highly organic medial silt loam; 60 percent black (10YR 2/1) broken face and 40 percent very dark brown (7.5YR 2.5/2) broken face moist, 60 percent dark gray (10YR 4/1) broken face and 40 percent brown (7.5YR 4/2) broken face dry; weak coarse subangular blocky structure; friable, slightly hard, slightly sticky, nonplastic, weakly smeary; common very fine and fine roots throughout; common very fine and fine tubular pores; 5 percent channers and 15 percent flagstones; moderately acid (pH 5.6), very strongly alkaline (NaF pH 9.9); 28 percent volcanic glass; abrupt wavy boundary. (5 to 24 cm, 2 to 9 in thick)
2Bw--67 to 90 cm (26 to 35 in); channery silt loam; olive brown (2.5Y 4/3) broken face moist, light yellowish brown (2.5Y 6/3) broken face dry; weak medium granular structure; friable, slightly hard, slightly sticky, nonplastic, nonsmeary; common very fine tubular pores; 20 percent channers and 10 percent flagstones; moderately acid (pH 5.7), very strongly alkaline (NaF pH 9.2); 1 percent volcanic glass; clear wavy boundary. (15 to 25 cm, 6 to 10 in thick)
2C--90 to 110 cm (35 to 43 in); very flaggy fine sandy loam; dark olive brown (2.5Y 3/3) broken face moist, light olive brown (2.5Y 5/3) broken face dry; massive; friable, slightly hard, slightly sticky, nonplastic, nonsmeary; 20 percent channers and 30 percent flagstones; moderately acid (pH 5.8), very strongly alkaline (NaF pH 9.0); 3 percent volcanic glass; abrupt irregular boundary. (10 to 25 cm, 4 to 10 in thick)
3Cr--110 to 135 cm (43 to 53 in); weakly to moderately coherent mudstone bedrock.
TYPE LOCATION: Nulato Hills - Continental Divide and Blackburn Hills Soil Survey Area, Alaska; latitude 64.2954568, longitude-160.0522120, datum WGS84, UTM north 7130359.73 and UTM east 449079.94, 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: 15 to 26 cm (6 to 10 in)
Thickness of folistic epipedon: 15 to 26 cm (6 to 10 in)
Thickness of andic soil properties: 5 to 24 cm (2 to 9 in)
Thickness of umbric epipedon: 18 to 79 cm (7 to 31 in)
Thickness of cambic horizon: 15 to 25 cm (6 to 10 in)
Depth to paralithic contact: 100 to 150 cm (40 to 40 in)
Oe and Oa horizon:
Hue: 5YR, 7.5YR, or 10YR
Value: 2 to 3 moist, 4 or 5 dry
Chroma: 1 to 3
Texture: moderately or highly decomposed plant material
Organic matter: 60 to 90 percent
Reaction class: ultra acid to strongly acid (pH 3.0 to 5.5)
Bw horizon:
Hue: 10YR or 2.5Y
Value: 3 or 4 moist, 5 to 6 dry
Chroma: 3 or 4
Texture: highly organic silt loam, or their channery analogues
Sand: 10 to 40 percent
Clay: 4 to 12 percent
Silt: 50 to 80 percent
Rock fragments: 0 to 30 percent
Organic matter: 10 to 19 percent
Reaction class: extremely acid to strongly acid (pH 3.5 to 5.5)
A horizon:
Hue: 5YR, 7.5YR, or 10YR
Value: 2 to 3 moist, 4 or 5 dry
Chroma: 1 to 3
Texture: highly organic silt loam, highly organic silt, or their channery analogues
Sand: 5 to 40 percent
Clay: 4 to 12 percent
Silt: 50 to 91 percent
Rock fragments: 15 to 50 percent
Organic matter: 10 to 19 percent
Reaction class: extremely acid to very strongly acid (pH 3.5 to 5.0)
Bhs horizon:
Hue: 2.5YR, 5YR, 7.5YR, or 10YR
Value: 2 to 3 moist, 4 or 5 dry
Chroma: 1 to 4
Texture: highly organic medial silt loam, or their flaggy analogues
Sand: 15 to 40 percent
Clay: 4 to 10 percent
Silt: 50 to 80 percent
Rock fragments: 0 to 30 percent
Channers: 0 to 15 percent
Flagstones: 0 to 20 percent
Organic matter: 10 to 19 percent
Bulk density: 0.5 to 1.0 g/cm3
Al plus 1/2 Fe:1 to 2 percent
Volcanic glass content: 20 to 35 percent
Phosphorus retention: 70 to 100 percent
Reaction class: extremely acid to moderately acid (pH 3.5 to 6.0)
2Bw horizon:
Hue: 10YR or 2.5Y
Value: 3 or 4 moist, 5 or 6 dry
Chroma: 3 or 4
Texture: silt loam, loam, or their channery analogues
Sand: 10 to 45 percent
Clay: 6 to 16 percent
Silt: 39 to 80 percent
Rock fragments: 15 to 59 percent
Channers:15 to 55 percent
Flagstones: 0 to 30 percent
Organic matter: 2 to 4 percent
Reaction class: very strongly acid to moderately acid (pH 4.5 to 6.0)
2C horizon:
Hue: 10YR or 2.5Y
Value: 3 or 4 moist, 5 or 6 dry
Chroma: 2 or 3
Texture: loam, fine sandy loam, or their channery or flaggy analogues
Sand: 34 to 70 percent
Clay: 4 to 16 percent
Silt: 14 to 50 percent
Rock fragments: 35 to 59 percent
Channers: 15 to 45 percent
Flagstones: 0 to 35 percent
Organic matter: 1 to 3.5 percent
Reaction class: very strongly acid to moderately acid (pH 4.5 to 6.0)
3Cr horizon
Weakly to moderately coherent mudstone bedrock.
Some pedons have a lithic contact at depths between 58 cm (50 in) and 180 cm (71 in)
COMPETING SERIES: none
GEOGRAPHIC SETTING:
Elevation: 100 to 550 meters (325 to 1805 feet)
Parent material: herbaceous organic material over volcanic ash influenced loamy colluvium over gravelly loamy colluvium over gravelly loamy residuum weathered from mudstone
Landform: mountain slopes and hillslopes
Slopes: 20 to 70 percent
Mean annual precipitation: 300 to 600 mm (12 to 20 in)
Mean annual air temperature: -5 to -1 degrees C. (23 to 30 degrees F.)
Frost free period: 70 to 90 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Apkun, Atkaktuk, Aullasik, Iyagak, Iyyagrik, Kimigaak, Kinak, Niakuk, Piksrun, Siku, Sikuruk, Tagluk, Tui, Tumi, and Urgiilik soils.
Apkun soils have a lithic contact at depths betweeen 50 to100 cm (20 to 40 in), have a gelic soil temperature regime, lack a folistic epipedon, lack a cambic horizon, lack andic soil properties, and occur on similar landforms on mountainflanks, center third
Atkaktuk soils have a fragmental layer at depths less than 50 cm (20 in), have a gelic soil temperature regime, lack a folistic epipedon, lack a cambic horizon, lack andic soil properties, and occur on similar landforms on mountainflanks, center-third
Aullasik soils have a lithic contact at depths between 150 to 200 cm (60 to 80 in), lack a folistic epipedon, lack andic soil properties, and occur on similar landforms on mountainflanks, center third
Iyagak soils have an ochric epipedon, have a fragmental particle-size class, lack andic soil properties and occur on similar landforms swales and mountainflanks, center third
Iyyagrik soils have lithic contact at depths between 100 to 150cm (40 to 60 in), have a mollic epipedon, lack a folistic epipedon, lack a cambic horizon, lack andic soil properties, and occur on mountainflanks, upper third
Kimigaak soils have a lithic contact at depths between 50 to 100cm (20 to 40 in), have an ochric epipedon, and occur on ridges on hills
Kinak soils lack a folistic epipedon, lack andic soil properties, and occur on headslopes of hills
Niakuk soils have a fragmental layer at depths less than 100 cm (40 in), have a lithic contact at depths between 100 to 150 cm (39 to 59 in), have an ochric epipedon, lack andic soil properties, and occur on mountainflanks, upper third
Piksrun soils have a gelic soil temperature regime, lack a folistic epipedon, lack a cambic horizon, lack andic soil properties, and occur on similar landforms on mountainflanks, center and upper third
Siku soils have aquic conditions starting between 0 to 25 cm (0 to 10 in), have a reduced matrix starting between 0 to 25 cm (0 to10 in), have a gelic soil temperature regime, lack an umbric epipedon, lack a cambic horizon, lack andic soil properties, and occur on mountainflanks, lower third
Sikuruk soils have aquic conditions starting between 0 to 25 cm (0 to 10 in), have a reduced matrix starting between 25 to 50 cm (10 to 20 in), have a gelic soil temperature regime, have permafrost, lack a cambic horizon, lack andic soil properties, and occur on saddles of hills
Tagluk soils have a mollic epipedon, lack a folistic epipedon, lack a cambic horizon, lack andic soil properties, and occur on headslopes of hillslopes
Tui soils have an ochric epipedon, lack andic soil properties, and occur on nose slopes of hillslopes
Urgiilik soils have a lithic contact at depths between 50 to 100 cm (20 to 40 in), have an ochric epipedon, lack andic soil properties, and occur on similar landforms on mountainflanks, center third
DRAINAGE AND PERMEABILITY:
Drainage class: well drained
Saturated Hydraulic Conductivity: very high in the Oe and Oa horizons, moderately high to high in the Bw, A, Bhs, 2Bw and 2C horizons
Permeability: rapid to very rapid in the Oe and Oa horizons, moderate to moderately rapid in the Bw, A, Bhs, and 2Bw horizons, moderate to rapid in the 2C horizon
Runoff: medium
USE AND VEGETATION:
Use: wildlife habitat, recreation and subsistence.
Native vegetation: Sitka alder, bluejoint, spreading woodfern, beauverd spirea, stiff clubmoss, tealeaf willow, red currant
DISTRIBUTION AND EXTENT: MLRA 240, Nulato Hills-Southern Seward Peninsula Highlands, Alaska. 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: 46 to 110 cm (18 to 43 in)
Folistic epipedon: 0 to 21 cm (0 to 8 in) (Oe and Oa horizons)
Umbric epipedon: 21 to 67 cm (8 to 26 in) (Bw, A, and Bhs horizons)
Volcanic glass: 21 to 110 cm (8 to 43 in) (Bw, A, Bhs, 2Bw, and 2C horizons)
Spodic materials : 46 to 67 cm (18 to 26 in) (Bhs horizon)
Andic soil properties: 46 to 67 cm (18 to 26 in) (Bhs horizon)
Lithological discontinuity: 67 to 110 cm (26 to 43 in) (2Bw and 2C horizons)
Cambic horizon: 67 to 90 cm (26 to 35 in) (2Bw horizon)
Lithologic discontinuity: 110 to 135 cm (43 to 53) (3Cr horizon)
Paralithic contact: 110 to 135 cm (43 to 53 in) (3Cr horizon)
ADDITIONAL DATA:
User pedon ID: S2021AK180916
KSSL lab pedon: 22N0121
National Cooperative Soil Survey
U.S.A.