LOCATION BIGELK ORTentative Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Vitrandic Haploxerolls
TYPICAL PEDON: Bigelk very stony ashy silt loam - forested, on a 55 percent planar northfacing slope at an elevation of 4,300 feet. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 2 inches; slightly decomposed needles and leaves
A--2 to 14 inches; dark brown (10YR 3/3) very stony ashy silt loam, dark yellowish brown (10YR 4/4) dry; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine, and common medium and coarse roots; many fine irregular pores; 10 percent gravel, 15 percent cobbles and 15 percent stones; neutral (pH 7.3); clear wavy boundary. (7 to 14 inches thick)
2Bwb1--14 to 26 inches; dark yellowish brown (10YR 4/4) extremely stony silt loam, yellowish brown (10YR 5/6) dry; weak medium and fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; many very fine, fine, medium and coarse roots; few fine tubular pores; 20 percent gravel, 20 percent cobbles and 20 percent stones; neutral (pH 7.0); clear smooth boundary. (8 to 12 inches thick)
2Bwb2--26 to 37 inches; dark yellowish brown (10YR 4/4) extremely stony silt loam, yellowish brown (10YR 5/4) dry; weak medium and fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; many fine, and common medium and coarse roots; few fine tubular pores; 25 percent gravel, 20 percent cobbles and 20 percent stones; neutral (pH 7.0); gradual smooth boundary. (7 to 24 inches thick)
2Bwb3--37 to 50 inches; dark yellowish brown (10YR 4/4) extremely stony loam, yellowish brown (10YR 5/4) dry; weak medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine, common medium and few coarse roots; few fine tubular pores; 30 percent gravel, 20 percent cobbles and 20 percent stones; neutral (pH 7.0). (17 inches thick)
2BC--50 to 61 inches; dark yellowish brown (10YR 4/4) extremely stony loam, yellowish brown (10YR 5/4) dry; weak fine subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common fine and medium roots; 35 percent gravel, 20 percent cobbles and 20 percent stones; neutral (pH 7.0). (13 to 25 inches thick)
TYPE LOCATION: Baker County, Oregon
Section 3 (NE 1/4, NE 1/4, SW 1/4), T. 7 S., R. 45 E.
Latitude: 44 degrees, 59 minutes, 11 seconds N
Longitude: 117 degrees, 11 minutes, 42 seconds W
UTM coordinates: zone 11; north 4981239.7 meters, east 484626.9 meters; NAD27
USGS Quadrangle: Jimtown
RANGE IN CHARACTERISTICS:
Soil Temperature: frigid regime
Mean Annual Soil Temperature: 39 to 45 degrees F
Mean Summer Soil Temperature: 47 to 52 degrees F
Mean Winter Soil Temperature: 32 to 37 degrees F
Soil Moisture: xeric regime; dry 45 to 60 consecutive days in summer
Particle-size Control Section: from 10 to 40 inches below mineral soil surface
clay content, average: 7 to 17 percent
rock fragment content, average: 50 to 75 percent; rock shape: rounded to subrounded
Diagnostic Horizons and Features:
vitrandic subgroup properties: upper boundary at the mineral surface; 7 to 14 inches thick
Al+1/2Fe (ammonium oxalate): 0.4 to 1.0 percent[CoFu1]
P retention: 30 to 50 percent
0.02-2.0 mm fraction: 30 to 40 percent of fine earth
glass content in the 0.02-2.0mm fraction: 35 to 50 percent
mollic epipedon: 10 to 19 inches thick
cambic horizon: 13 to 51 inches thick
ultic subgroup feature: base saturation (sum of cations) 55 to 70 percent in A and 2Bwb1 horizons
A horizon:
color, moist: 10YR 2/2, 3/2, 3/3
color, dry: 10YR 4/3, 4/4, 5/2, 5/3
texture: STX-ASHY-SIL, STV-ASHY-SIL, STX-ASHY-L
clay content: 5 to 14 percent
rock fragment content: 40 to 70 percent total
gravel: 10 to 20 percent
cobbles: 10 to 25 percent
stones: 15 to 25 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
base saturation (sum of cations) 55 to 70 percent
2ABb horizon, present in some pedons: (3 to 5 inches thick)
color, moist: 10YR 3/2, 3/3
color, dry: 10YR 4/3, 4/4, 4/6, 5/4
texture: STX-L, STX-SIL
clay content: 5 to 17 percent
rock fragment content: 60 to 75 percent total
gravel: 20 to 25 percent
cobbles: 20 to 25 percent
stones: 20 to 25 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
base saturation (sum of cations) 55 to 70 percent
2Bwb horizon:
color, moist: 10YR 3/4, 4/4, 5/4
color, dry: 10YR 5/4, 5/6, 6/6
texture: STX-L, STX-SIL
clay content: 8 to 17 percent
rock fragment content: 65 to 80 percent total
gravel: 25 to 30 percent
cobbles: 20 to 25 percent
stones: 20 to 35 percent
reaction: moderately acid to neutral; pH: 5.6 to 7.3
2BC horizon:
color, moist: 2.5Y 5/4; 10YR 4/4, 5/4, 5/6
color, dry: 2.5Y 6/4; 10YR 5/4, 5/6, 6/4
texture: STX-SL, CBX-SL, STX-SIL, STX-L
clay content: 5 to 22 percent
rock fragment content: 65 to 85 percent total
gravel: 25 to 35 percent
cobbles: 20 to 25 percent
stones: 15 to 25 percent
reaction: moderately acid to neutral; pH: 5.6 to 7.3
COMPETING SERIES:
Bearspring: very deep; formed in granitic colluvium; minor volcanic ash influence (glass content 5 to 20 percent); particle-size control section averages 35 to 50 percent rock fragments; rock fragments are angular; dry 60 to 75 consecutive days in summer
Cassal: deep (40 to 60 inches) to densic contact (dense till); volcanic ash influenced layer (glass content 5 to 20 percent) 12 to 18 inches thick with discontinuity between ashy layer and till substratum; distinct redoximorphic features at 30 to 45 inches; dry 60 to 75 consecutive days in summer
Cherrycreek: deep (40 to 60 inches) to a lithic contact (basalt); does not have an organic horizon above surface of mineral soil (not forested); mixed mantle of volcanic ash and loess (glass content 15 to 30 percent), 35 to 50 inches thick; mollic epipedon is 20 to 35 inches thick; dry 60 to 75 consecutive days in summer
Coyotebluff: deep (40 to 60 inches) to a lithic contact (granite); mixed volcanic ash mantle (glass content 35 to 50 percent) 7 to 14 inches thick; mollic epipedon is 20 to 26 inches thick; particle-size control section averages 3 to 12 percent clay
Deck: moderately deep (20 to 40 inches) to a lithic contact (metavolcanic rock); particle-size control section averages 20 to 34 percent clay; dry 60 to 75 consecutive days in summer
Eastpine: moderately deep (20 to 40 inches) to a lithic contact (metasedimentary rock); minor volcanic ash influence (glass content 5 to 15 percent)
Egyptcreek: moderately deep (20 to 40 inches) to a lithic contact (welded tuff); mollic epipedon is 7 to 14 inches thick; dry 75 to 90 consecutive days in summer
Fredonyer: moderately deep (20 to 40 inches) to lithic contact (andesite or basalt); does not have organic horizon above surface of mineral soil (not forested); mollic epipedon is 20 to 40 inches thick; dry more than 90 consecutive days in summer
Golfer: moderately deep (20 to 40 inches) to a paralithic contact (weathered granite); minor influence of volcanic ash (glass content 5 to 15 percent); particle-size control section averages 2 to 10 percent clay; dry 60 to 75 consecutive days in summer
Grubcreek: moderately deep (20 to 40 inches) to a lithic contact (andesite, andesitic basalt or basalt); minor volcanic ash influence (glass content 5 to 15 percent); particle-size control section averages 18 to 33 percent clay; dry 60 to 75 consecutive days in summer
Kettlecreek: deep (40 to 60 inches) to a lithic contact (argillite); minor volcanic ash influence (glass content 5 to 15 percent); dry 60 to 75 consecutive days in summer
Longs: deep (40 to 60 inches) to a lithic contact (basalt); mollic epipedon is 20 to 45 inches thick; subsoil has faint clay films on ped faces; particle-size control section averages 18 to 27 percent clay; dry 45 to 75 consecutive days in summer
Midpeak: moderately deep (20 to 40 inches) to a lithic contact (breccia); mixed volcanic ash mantle (glass content 5 to 20 percent) with discontinuity between mantle and buried cambic horizon; dry 60 to 75 consecutive days in summer
Mineral: moderately deep (20 to 40 inches) to a lithic contact (granitic rocks); volcanic ash influence (glass content 5 to 20 percent); dry 60 to 75 consecutive days in summer
Peahke: moderately deep (20 to 40 inches) to a paralithic contact; volcanic ash mantle (glass content 20 to 30 percent), 7 to 14 inches thick; particle-size control section averages 18 to 30 percent clay, and has 60 to 70 percent channers
Piersonte: very deep; formed in colluvium from shale; mollic epipedon is 20 to 35 inches thick; particle-size control section averages 18 to 30 percent clay, rock fragments are mostly shale channers; dry 60 to 90 consecutive days in summer
Porch: moderately deep (20 to 40 inches) to lithic contact (argillite); rock fragments are angular; dry 60 to 75 consecutive days in summer
Scoap: very deep; formed in till or outwash materials of mixed lithology; mollic epipedon is 20 to 30 inches thick; dry 60 to 75 consecutive days in summer
Shalrock: moderately deep (20 to 40 inches) to a lithic contact (sandstone); mixed volcanic ash mantle (glass content 5 to 15 percent); with discontinuity between mantle and substratum; particle-size control section averages 25 to 50 percent medium and coarse sand; dry 60 to 75 consecutive days in summer
Shilling: very deep; formed in colluvium from basalt; particle-size control section averages 18 to 27 percent clay; dry 45 to 75 consecutive days in summer
Umatilla: very deep; formed in colluvium from basalt; mollic epipedon is 20 to 30 inches thick (mollic colors throughout); discontinuity between ashy layer and subsoil horizons; particle-size control section averages 25 to 35 percent clay; dry 60 to 80 consecutive days in summer
Webbgulch: moderately deep (20 to 40 inches) to a lithic contact (andesitic basalt or basalt); rock fragments are subangular; dry 60 to 75 consecutive days in summer
Yellcreek: very deep; formed in colluvium of mixed lithology; minor volcanic ash influence (glass content 5 to 20 percent) with discontinuity between volcanic ash influence zone and substratum; mollic epipedon is 7 to 15 inches thick; rock fragments are angular; dry 60 to 75 consecutive days
GEOGRAPHIC SETTING:
Landform: lateral moraines in glaciated mountain valleys
Slope gradient: 0 to 90 percent
Parent material: mixed volcanic ash, loess and colluvium overlying till
Lithology: mixed
Elevation: 3,800 to 5,300 feet
Climate: cold, wet winters and cool, dry summers
Mean annual precipitation: 40 to 50 inches
Mean annual air temperature: 39 to 44 degrees F
Frostfree period: 40 to 100 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Gulliford: on well drained channel shelves, with sandy-skeletal substratum and oxyaquic conditions within 20 inches, and under moist meadow vegetation
Inkler: on footslopes and north aspects; thin undisturbed volcanic ash mantle, under Douglas-fir, and western larch with an understory of common snowberry, mallow ninebark and pinegrass
Lakefork: on moraines with gentle slopes and north aspects; very deep soil with ash mantle greater than 14 inches thick and more than 35 percent rock fragments; under grand fir, western larch, Engelmann spruce, queen's cup beadlily, Hooker's fairybell, mountain brome, sedges and pinegrass
Melloe: on poorly drained floodplains; with loamy-skeletal particle-size control section, aquic conditions within 10 to 18 inches, under wet meadow vegetation
Terlough: on somewhat poorly drained low terraces with a mollic epipedon, loamy-skeletal substratum and oxyaquic conditions within 16 inches, under fir and spruce forest with udic moisture regime
Tertoo: on well drained relict high terraces and toeslope fans with thick ash mantle over loamy-skeletal materials and xeric moisture regime under grand fir and ponderosa pine forest
Torchspring: on toe slopes and glaciated valley floors; very deep with ash mantle over an argillic horizon, under grand fir, western larch, birchleaf spiraea, big huckleberry, showy aster, pinegrass and mountain brome
Twocolor: on moraines with gentle slopes and south aspects; very deep soil with ash mantle greater than 14 inches thick and more than 35 percent rock fragments; under grand fir, western larch, big huckleberry, prince's pine and pinegrass
DRAINAGE AND PERMEABILITY:
Drainage: well drained
Permeability: moderate to moderately rapid
USE AND VEGETATION:
Use: livestock grazing, timber production, watershed and recreation.
Potential native vegetation: grand fir, Douglas-fir, ponderosa pine, birchleaf spiraea, Rocky Mountain maple, big huckleberry, Oregon grape, common snowberry, showy aster, yarrow, white-flowered hawkweed, pinegrass, mountain brome and elk sedge.
Plant Association: ABGR/SPBE (grand fir/birchleaf spiraea); may include: ABGR/ACGL (grand fir/rocky mountain maple) and ABGR/VAME (grand fir/big huckleberry)
DISTRIBUTION AND EXTENT:
Distribution: MLRA: 43c, Blue Mountains, northeastern Oregon
Extent: small
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Wallowa-Whitman National Forest, Oregon 2008. The source of the name is a stream.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon: 2 to 14 inches; A horizon
cambic horizon: 14 to 50 inches; 2Bwb1, 2Bwb2 and 2Bwb3 horizons
vitandic supgroup properties: 2 to 14 inches; A horizon
particle-size control section: 12 to 42 inches; A, 2Bwb1, 2Bwb2 and 2Bwb3 horizons