LOCATION BLACKCOVE               AK

Established Series
SAS/MPS
02/2022

BLACKCOVE SERIES


Landscape--hills, valley
Landform--depression
Slope--0 to 5 percent
Parent material--mossy organic material over loess
Mean annual precipitation--about 480 mm
Mean annual air temperature--about -3 degrees C
Depth class--very deep
Drainage class--very poorly drained
Soil moisture regime--peraquic
Soil temperature regime--cryic
Soil moisture subclass--typic

TAXONOMIC CLASS: Euic Typic Cryosaprists

TYPICAL PEDON: Blackcove peat on a south southeast facing linear, linear wet meadow on a slope of 1 percent at an elevation of 180 m (The soil was wet throughout the profile when described on June 27, 2018.)

Oi--0 to 15 cm; peaty slightly decomposed plant material, reddish yellow (7.5YR 7/8) dry, strong brown (7.5YR 5/8) moist; common very fine and fine roots; very strongly acid (pH 5.0); abrupt smooth boundary

Oe--15 to 25 cm; mucky peat, moderately decomposed plant material, brownish yellow (10YR 6/6) dry, dark yellowish brown (10YR 4/6) moist; many very fine and common fine and medium roots; moderately acid (pH 5.8); abrupt smooth boundary

Oa--25 to 180 cm; mucky highly decomposed plant material, dark gray (10YR 4/1) dry, black (10YR 2/1) moist; many very fine and common fine roots; slightly acid (pH 6.2); abrupt smooth boundary

Cg--180 to 200 cm; silt loam, 98 percent greenish gray (10Y 6/1) and 2 percent brownish yellow (10YR 6/6) dry, 98 percent dark greenish gray (10Y 4/1) and 2 percent dark yellowish brown (10YR 4/6) moist; slightly acid (pH 6.2)

TYPE LOCATION: Yukon-Koyukuk Census Area County, Alaska, latitude 63.1355300 longitude -160.8085120 degrees, datum WGS84 (Coordinates determined with a GPS unit)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--0 to 3 degrees C
Soil moisture control section--saturated at the soil surface during much of the growing season
Aquic conditions--throughout the profile
Thickness of sapric soil materials--115 to 155 cm
Total thickness of organic layers--greater than 130 cm

Oi horizon
Value--3 to 5 moist, 5 to 7 dry
Chroma--6 to 8 moist
Reaction--4.5 to 5.5
Organic matter content--35 to 55 percent
Rubbed fiber content--40 to 100 percent
Thickness--10 to 20cm

Oe horizon
Hue--7.5YR or 10YR
Value--2 to 4 moist, 4 to 6 dry
Chroma--2 to 6
Reaction--5.4 to 6.4
Organic matter content--35 to 55 percent
Rubbed fiber content--17 to 40 percent
Thickness--10 to 35 cm

Oa horizon
Hue--7.5YR or 10YR
Value--2 to 3 moist, 4 to 5 dry
Chroma--1 or 2
Reaction--5.0 to 6.0
Organic matter content--35 to 55 percent
Rubbed fiber content--0 to 17 percent
Sodium pyrophosphate color value and chroma-when chroma is 2, value is 5 or less; when chroma is 3, value is 6 or less
Thickness--85 to 155 cm

Cg horizon
Hue--10Y or 2.5Y
Value--4 or 5 moist, 6 or 7 dry
Chroma--1 or 2
Fine-earth texture--silt, silt loam
Clay--5 to 13 percent
Sand--10 to 30 percent
Organic carbon--1 to 2 percent
Reaction--5.5 to 6.3

COMPETING SERIES:
* Yamsay--no mineral soil layers present, winter soil temperature does not range below 0 degrees C, herbaceous organic material; lake beds, channels, valley floors, sag ponds and depressional areas of lava plateaus
* Stirfry--folistic epipedon, mossy organic material over volcanic ash and pumice; drainageways of a lava plateau
* Karheen--coarse fragments present; organic material, which is underlain, and intermixed, with beach deposits; uplifted beaches adjacent to tidal water

GEOGRAPHIC SETTING:
*Elevation--50 to 400 m
*Climate--warm, moist summers; cold, dry winters
*Mean annual precipitation--460 to 550 mm
*Mean annual air temperature-- -5 to -1 degrees C
*Frost-free period--55 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS:
* Nuna--mineral soil layer exists within 130 cm of the surface; thermokarst depressions on terraces

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
*Drainage class--very poorly drained
*Saturation during normal years--saturated throughout the profile during the growing season
*Ponding--frequent, very long
*Saturated hydraulic conductivity (Ksat)--moderately high or high in the organic soil horizons, moderately high in the mineral soil horizons

USE AND VEGETATION:
Use--wildlife habitat, recreation, subsistence
Potential native vegetation--boreal bog sedge, water sedge, bog rosemary, dwarf birch, Alaska bog willow, resin birch, black crowberry, water horsetail, purple marshlocks, sphagnum, fewflower sedge, sparseflower sedge, blueberry willow, roundleaf sundew, tall cottongrass,

DISTRIBUTION AND EXTENT: Nulato Hills-Southern Seward Peninsula Highlands, Alaska; MLRA 240; small extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA

SERIES ESTABLISHED: Nulato Hills BLM area, Nome Census Area, Alaska; 2021

REMARKS:
Diagnostic horizons and features recognized in this pedon
*Surface tier--zone from 0 to 30 cm
*Subsurface tier--zone from 30 to 90 cm
*Bottom tier--zone from 90 to 130 cm
*Thickness of organic layers--180 cm
*Aquic conditions--present throughout the profile
*Fibric soil materials--0 to 15 cm
*Hemic soil materials--15 to 25 cm
*Sapric soil materials--25 to 180 cm
*Reduced matrix--180-200 cm


National Cooperative Soil Survey
U.S.A.