LOCATION RIME AK
Established Series
SDB/MJS
08/2025
RIME SERIES
Depth class: very deep
Drainage class: well drained
Parent material: mossy organic material over silty loess over sandy alluvium
Landscape: mountains
Landform: flood plains and river valleys
Slope: 0 to 5 percent
Mean annual precipitation: about 600 mm (24 in)
Mean annual air temperature: about -3 degrees C (27 F)
Frost-free period: 32 to 71 days
TAXONOMIC CLASS: Sandy-skeletal, mixed Fluventic Haplocryepts
TYPICAL PEDON: Rime moderately decomposed plant material in a white spruce community on a flood plain with a slope of 5 percent at an elevation of 639m (2095 ft).
Oi--0 to 12 cm (0 to 5 in); slightly decomposed plant material, dark brown (7.5YR 3/2) broken face moist; many very fine and fine, few medium and many coarse roots throughout; very strongly acid (pH 4.9); clear wavy boundary (10 to 15 cm, 4 to 6 in)
Oe--12 to 21 cm (5 to 8 in); moderately decomposed plant material, very dark brown (10YR 2/2) broken face moist; many very fine and fine, few medium, and many coarse roots throughout; very strongly acid (pH 4.8); abrupt wavy boundary (7 to 12 cm, 3 to 5 in)
Bw--21 to 37 cm (8 to 15 in); silt loam, dark yellowish brown (10YR 3/4) broken face moist; moderate medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; nonsmeary; common very fine, fine, and few medium roots throughout; very fine dendritic tubular pores; extremely acid (pH 4.0); abrupt wavy boundary (15 to 20 cm, 6 to 8 in)
2C--37 to 150 cm (15 to 59 in); very cobbly sand, very dark grayish brown (2.5Y 3/2) broken face moist; single grain; loose, nonsticky, nonplastic; nonsmeary; few very fine roots throughout; interstitial pores; 20 percent subangular gravels by volume, 35 percent subrounded cobbles by volume; very strongly acid (pH 4.5) (103 to 118 cm, 40 to 46 in)
TYPE LOCATION: North Copper River Soil Survey Area, Alaska; latitude 63.06838, longitude -143.35051, UTM 6995380.00 north and UTM 381238.92 east, zone 7, Datum WGS84.
RANGE IN CHARACTERISTICS:
Soil moisture regime: udic
Soil temperature regime: cryic
Mean annual soil temperature: 0 to 5 degrees C. (0 to 41 degrees F)
Thickness of organic material: 17 to 27cm (7 to 11 in)
Thickness of epipedon: 17 to 27 cm (7 to 11 in)
Thickness of cambic horizon: 15 to 20 cm (6 to 8 in)
Depth to lithologic discontinuity: 32 to 47 cm (13 to 19 in)
Oi and Oe horizon:
Hue: 7.5YR or 10YR
Value: 2 to 3
Chroma: 1 to 3
Texture: Slightly decomposed plant material, moderately decomposed lant material
Organic matter: 60 to 90 percent
Reaction class: very strongly acid to strongly acid (pH 4.5 to 5.5)
Bw horizon:
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 2 to 4
Texture: silt loam
Sand: 25 to 40 percent
Silt: 50 to 62 percent
Clay: 10 to 16 percent
Organic matter: 4 to 6 percent
Reaction class: extremely acid to strongly acid (pH 3.5 to 5.5)
2C horizon:
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 2 to 4
Texture: extremely cobbly sand, very cobbly sand
Sand: 87 to 95 percent
Silt: 1 to 8 percent
Clay: 4 to 8 percent
Rock fragments: 35 to 70 percent
Gravels: 15 to 25 percent
Cobbles: 20 to 45 percent
Organic matter: 0.5 to 1.5 percent
Reaction class: extremely acid to strongly acid (pH 4.0 to 5.5)
Some pedons have a lithic contact and/or sandy-skeletal substratum at depths greater than 127 cm (50 in).
COMPETING SERIES: These are the
Marysslough (AK) soils.
Marysslough soils occur at elevations of 0 to 8 m (0 to 26 ft) on flood plains and the leeward side of coast berms in shore complexes.
GEOGRAPHIC SETTING:
Elevation: 100 to 1000 meters (330 to 3280 ft)
Parent material: mossy organic material over silty loess over sandy alluvium
Landform: flood plains and river valleys
Slopes: 0 to 5 percent
Mean annual precipitation: 400 to 800 mm (16 to 31 in)
Mean annual air temperature: -2 to -4 degrees C. (28 to 25 degrees F)
Frost-free period: 32 to 71 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Dackey (AK), Drashner (AK), Slimecreek (AK), and
Sonderna (AK) series.
Dackey soils are somewhat poorly drained, have fine sandy loam surface horizon over stratified alluvium, and occur on floodplains and low stream terraces.
Drashner soils are somewhat poorly drained, have a histic epipedon, and occur on mountains and hillslopes.
Slimecreek soils are somewhat poorly drained, have aquic conditions starting between 14 and 39 cm (6 and 15 in) deep, and occur on floodplains in mountains.
Sonderna soils have an umbric epipedon, and occur on alluvial fans and fan terraces in mountains.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: well drained
Saturated Hydraulic Conductivity: very high in the Oi, Oe, and 2C horizons, moderately high in the Bw horizon.
Permeability: very rapid in the Oi, Oe, and 2C horizons, moderate in the Bw horizon.
Runoff: low
USE AND VEGETATION:
Use: wildlife habitat, recreation, and subsistence
Native vegetation: White spruce, feather moss
DISTRIBUTION AND EXTENT: MLRA 228 Interior Alaska mountains.
Extent: limited.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Wasilla, Alaska
SERIES ESTABLISHED: North Copper River Soil Survey, Alaska, 2024.
REMARKS: Diagnostic features and horizons recognized in this profile include:
Particle-size control section: 46 to 121 cm (18 to 48 in)
Folistic epipedon: 0 to 21 cm (0 to 8 in) (Oi, Oe horizons)
Cambic horizon: 21 to 37 cm (8 to 15 in) (Bw horizon)
Lithologic discontinuity: 37 to 150 cm (15 to 59 in) (2C horizon)
ADDITIONAL DATA:
User pedon Id: 2023AK261242
National Cooperative Soil Survey
U.S.A.