LOCATION NORTHRIVER              AK

Established Series
MPS/SAS
12/2022

NORTHRIVER SERIES


Landscape--hills, low mountains
Landform--hillslopes, mountain slopes
Slope--10 to 65 percent
Parent material--gravelly colluvium
Mean annual precipitation--about 495 mm
Mean annual air temperature--about -3 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--typic

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Dystrocryepts

TYPICAL PEDON: Northriver silt on an east southeast facing convex, linear backslope, on a slope of 40 percent at an elevation of 292 m (The soil was moist throughout when described on July 30, 2019.)

Oe--0 to 10 cm; moderately decomposed plant material, brown (7.5YR 4/3) dry, very dark brown (7.5YR 2.5/3) moist; many very fine, medium, and coarse, and common fine roots; extremely acid (pH 4.2); abrupt smooth boundary

A--10 to 19 cm; silt, dark gray (7.5YR 4/1) dry, black (7.5YR 2.5/1) moist; very coarse, subangular blocky structure; very friable, nonsticky, nonplastic; common very fine, fine, and medium roots; very strongly acid (pH 4.6); abrupt smooth boundary

2Bw--19 to 35 cm; very channery silt loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; very friable, nonsticky, nonplastic; common fine roots; common very fine pores; 50 percent channers; extremely acid (pH 4.4); clear smooth boundary

2C--35 to 150 cm; extremely channery silt loam, light brownish gray (2.5Y 6/2) dry, dark grayish brown (2.5Y 4/2) moist; massive; very friable, nonsticky, nonplastic; 80 percent channers; very strongly acid (pH 5.0)

TYPE LOCATION: Nome Census Area, Alaska, latitude 63.6557310 longitude -160.5242510 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--dry less than 45 consecutive days in June through October (udic soil moisture regime)
Thickness of ochric epipedon--10 to 25 cm
Depth to lithologic discontinuity--10 to 25 cm
Thickness of cambic horizon--25 to 45 cm

Particle Size Control Section:
*Clay--8 to 14 percent
*Total fragments--40 to 80 percent gravels, channers, cobbles

Oe horizon
Thickness--5 to 15 cm

A horizon
Hue--7.5YR or 10YR
Value--2 to 3 moist, 4 or 5 dry
Chroma--1 or 2
Fine-earth texture--silt, silt loam
Clay--5 to 10 percent
Sand--5 to 30 percent
Organic carbon--8 to 12 percent
Sodium fluoride pH--8.4 to 11.6
Ratio of 1500 kPa water to measured clay--0.6 to 3.0
Reaction--4.0 to 5.2
Thickness-- 5 to 25 cm

2Bw horizon
Hue--10YR or 2.5Y
Value--3 or 4 moist, 5 or 6 dry
Chroma--2 to 4
Fine-earth texture--silt loam, sandy loam, loam
Clay--5 to 16 percent
Sand--5 to 50 percent
Organic carbon--3 to 5 percent
Total rock fragment content--30 to 50 percent
Total channer content--0 to 50 percent
Total gravel content--0 to 35 percent
Reaction--4.4 to 5.4
Thickness--15 to 35 cm

2C horizon
Hue--10YR or 2.5Y
Value--3 or 4 moist, 5 or 6 dry
Chroma--2 to 4
Fine-earth texture--silt loam, fine sandy loam, loam
Clay--7 to 15 percent
Sand--15 to 55 percent
Organic carbon--1 to 2 percent
Total rock fragment content--40 to 80 percent
Total channer content--0 to 80 percent
Total gravel content--0 to 35 percent
Total cobble content--0 to 45 percent
Reaction--4.6 to 5.6

COMPETING SERIES:
* Angel--shallow to paralithic contact, backslopes, shoulder, and summits of hills and low mountains, slope range is 0 to 60 percent
* Brigadier--shallow to paralithic contact, north facing hill and mountain sideslopes, slope range is 0 to 70 percent
* Gilmore--very shallow or shallow to paralithic contact, crests and hillslopes on hillsides, mountainsides and ridgetops, slope range is 0 to 70 percent
* Leighcan--albic horizon, mountain slopes, slope range is 0 to 70 percent
* Jeru--volcanic ash mantle, mountains, slope range is 5 to 75 percent
* Blacksnag--mountain slopes, mesas, and structural benches, slope range is 2 to 30 percent
* Afley--moderately deep to bedrock, mesa summits, alpine mountain slopes, and alpine basins, slope range is 0 to 70 percent

GEOGRAPHIC SETTING:
*Elevation--100 to 600 m
*Climate--warm, moist summers; cold, dry winters
*Mean annual precipitation--415 to 640 mm
*Mean annual air temperature-- -5 to -1 degrees C
*Frost-free period--55 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS:
* Kanguq--isotic mineralogy, moderately deep to paralithic contact; hillslopes and mountain slopes on hills and mountains

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
*Drainage class--well drained
*Saturation during normal years--none
*Saturated hydraulic conductivity (Ksat)--very high in the surface organic layer, high to moderately high throughout the rest of the profile

USE AND VEGETATION:
Use--wildlife habitat, recreation, subsistence
Potential native vegetation--black spruce, resin birch, bog blueberry, lingonberry, black crowberry, marsh Labrador tea, green alder, tealeaf willow, splendid feather moss, sphagnum, white spruce, Siberian alder, beaverd spirea, dwarf birch, woodland horsetail, dwarf raspberry, Bigelow's sedge, bluejoint, Moss, Schreber's big red stem moss, juniper polytrichum moss, quaking aspen, grayleaf willow, greygreen reindeer lichen, reindeer lichen, star reindeer lichen, common ladyfern, Alaska wild rhubarb

DISTRIBUTION AND EXTENT: Nulato Hills-Southern Seward Peninsula Highlands, Alaska; MLRA 240; moderate 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
*Particle-size control section--zone from 35 to 110 cm
*Ochric epipedon--zone from 0 to 19 cm
*Lithologic discontinuity--zone from 19 to 150 cm
*Cambic horizon--zone from 10 to 35 cm


National Cooperative Soil Survey
U.S.A.