LOCATION DEARDORF OR
Established Series
Rev. RJO/DAL
10/2012
DEARDORF SERIES
The Deardorf series consists of moderately deep, well-drained soils on ridges and shoulder slopes of mountains. Deardorf soils are formed in volcanic ash overlying colluvium from andesitic basalt. Slopes are 0 to 60 percent. The mean annual precipitation is about 29 inches and the mean annual temperature is about 38 degrees F.
TAXONOMIC CLASS: Ashy over loamy-skeletal, amorphic over isotic, frigid Typic Udivitrands
TYPICAL PEDON: Deardorf stony ashy silt loam - woodland, on a 10 percent north-facing slope at an elevation of 6,040 feet. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inches; needles and twigs
A--1 to 2 inches; very dark grayish brown (10YR 3/2) stony ashy silt loam, grayish brown (10YR 5/2) dry; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, and few medium roots; common fine irregular pores; 5 percent gravel, 5 percent cobbles and 5 percent stones; neutral (pH 7.0) clear wavy boundary. (1 to 4 inches thick)
Bw--2 to 17 inches; dark yellowish brown (10YR 3/4) stony ashy silt loam, very pale brown (10YR 7/4) dry; weak fine and very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine, medium and coarse roots; few fine tubular pores; 5 percent gravel, 5 percent cobbles and 10 percent stones; slightly acid (pH 6.5); clear wavy boundary. (13 to 19 inches thick)
2Eb--17 to 25 inches; brown (10YR 4/3) very stony loam, pale brown (10YR 6/3) dry; weak fine and very fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; few fine and medium tubular pores; 20 percent gravel, 20 percent cobbles and 20 percent stones; moderately acid (pH 5.6); clear smooth boundary. (0 to 9 inches thick)
2Bwb--25 to 35 inches; dark yellowish brown (10YR 4/4) extremely stony loam, light yellowish brown (10YR 6/4) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, few medium and coarse roots; few fine tubular pores; 20 percent gravel, 20 percent cobbles and 25 percent stones; moderately acid (pH 5.6); abrupt irregular boundary. (5 to 10 inches thick)
2R--35 inches; andesitic basalt bedrock
TYPE LOCATION: Baker County, Oregon
Section 6, T. 13 S., R. 36 E.
Latitude: 44 degrees, 27 minutes, 40 seconds N
Longitude: 118 degrees, 20 minutes, 40 seconds W
UTM Coordinates: Zone: 11; Northing: 4923968.5; Easting: 393048.5
USGS Quadrangle: Rail Gulch
RANGE IN CHARACTERISTICS:
Soil Temperature: frigid regime
Mean Annual Soil Temperature: 38 to 41 degrees F
Mean Summer Soil Temperature: 47 to 50 degrees F
Mean Winter Soil Temperature: 32 to 36 degrees F
Soil Moisture: udic regime; dry 30 to 40 days in summer
Particle-size Control Section: mineral soil surface to bedrock
Upper part (ashy): 14 to 20 inches thick
Clay content: 5 to 7 percent
Rock fragment content: 5 to 25 percent
Lower Part (loamy-skeletal): 7 to 21 inches thick
Clay content: 12 to 17 percent
Rock fragment content: 40 to 70 percent
Rock fragment shape: angular
Diagnostic Horizons and Features:
andic soil properties: upper boundary at the mineral surface; 14 to 20 inches thick
A1 + 1/2Fe(aox): 1.0 to 3.0 percent
bulk density: 0.65 to 1.0 g/cc
P retention: 40 to 90 percent
0.02-2.0 mm fraction: 40 to 60 percent of fine earth
glass content in the 0.02-2.0 mm fraction: 60 to 90 percent
water content at 1500 kPa (air dried): 5 to 12 percent
8Si + 2Fe (aox): 5 to 12 percent
8Si - 2Fe (aox): 4 to 8 percent
ochric epipedon: 1 to 4 inches thick
cambic horizon:
upper: 13 to 19 inches thick
lower: 5 to 10 inches thick
lithic contact depth: 20 to 40 inches
Major Horizons:
A horizon
color, moist: 7.5YR 2.5/2; 10YR 2/2, 3/2, 4/3, 5/4
color, dry: 10YR 4/3, 5/2, 5/3, 5/4, 6/3, 6/4
texture: ASHY-SIL, ST-ASHY-SIL
clay content: 5 to 8 percent
rock fragment content: 0 to 20 percent
gravel: 0 to 10 percent
cobbles: 0 to 5 percent
stones: 0 to 5 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
Bw horizon
color, moist: 7.5YR 3/4; 10YR 3/4, 4/4, 6/4
color, dry: 10YR 6/4, 7/4
texture: ASHY-SIL, ST-ASHY-SIL, CB-ASHY-SIL, GR-ASHY-SIL
clay content: 5 to 6 percent
rock fragment content: 5 to 30 percent
gravel: 5 to 20 percent
cobbles: 0 to 10 percent
stones: 0 to 10 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
2Eb horizon (some pedons have 2AEb horizons; other pedons do not have either)
color, moist: 7.5YR 3/4, 5/4; 10YR 3/3, 4/3, 4/4
color, dry: 7.5YR 4/4, 6/4; 10YR 6/3, 6/4
texture: STV-L, STX-SIL, GRV-L, STX-L
clay content: 10 to 16 percent
rock fragment content: 35 to 75 percent
gravel: 20 to 35 percent
cobbles: 10 to 25 percent
stones: 0 to 30 percent
reaction: moderately acid to slightly acid; pH: 5.6 to 6.5
2Bwb horizon (some pedons have 2BCb horizons)
color, moist: 7.5YR 4/3, 5/4; 10YR 4/4
color, dry: 7.5YR 5/4; 10YR 5/3, 6/3, 6/4
texture: STX-L, CBX-L, GRV-L
clay content: 12 to 17 percent
rock fragment content: 40 to 70 percent
gravel: 20 to 45 percent
cobbles: 20 to 30 percent
stones: 0 to 30 percent
reaction: moderately acid to slightly acid; pH: 5.6 to 6.5
COMPETING SERIES:
Boulderjud -- deep (40 to 60 inches) to a paralithic contact of weathered granite; ashy part of the pscs has 30 to 65 percent glass in the 0.02 to 2.0 mm fraction; has 2Bt horizons below the ash mantle; formed in coarse-silty volcanic ash over colluvium and residuum from granitic rocks
Bulgar -- very deep (>60 inches); ashy part of the pscs has 60 to 90 percent glass in the 0.02 to 2.0 mm fraction; ash mantle with greater than 5 percent rounded rock fragments; has 2EBb, 2Ab, 2AEb, or 2Eb buried surface horizon below the ash mantle; loamy-skeletal throughout the series control section (to 80 inches); glacial rock fragments in lower pscs are rounded; formed in volcanic ash over, mostly granitic, till
Bullroar -- very deep (>60 inches); ashy part of the pscs has 60 to 90 percent glass in the 0.02 to 2.0 mm fraction; ash mantle with less than 5 percent rounded rock fragments; texture in 2BC horizon is loam, sandy loam or loamy sand (loamy-skeletal); has 2EBb, 2ACb, or 2Eb buried surface horizon below the ash mantle; coarse sand and gravel in lower part of series control section (60 to 80 inches); rounded alluvial fragments in lower pscs; formed in volcanic ash over mixed alluvium
Ferguson -- very deep (>60 inches); texture of ash is very fine sandy loam; ashy part of the pscs has 30 to 55 percent glass in the 0.02 to 2.0 mm fraction; has 2Bw horizon; depth to 2C horizon with loamy coarse sand or sand (sandy-skeletal) is 40 to 60 inches; formed in volcanic ash over, mostly granitic, glaciofluvial deposits
Gutridge -- deep (40 to 60 inches) to a lithic contact; ashy part of the pscs has 60 to 90 percent glass in the 0.02 to 2.0 mm fraction; rock fragments in the loamy-skeletal part are subangular; formed in volcanic ash over colluvium from metasedimentary rock
Stalter -- moderately deep (20 to 40 inches) to a paralithic contact of weathered granite; ashy part of the pscs has 60 to 90 percent glass in the 0.02 to 2.0 mm fraction; formed in volcanic ash over colluvium and residuum from granite
Threecent -- moderately deep (20 to 40 inches) to a lithic contact; ashy part of the pscs has 60 to 90 percent glass in the 0.02 to 2.0 mm fraction; loamy-skeletal part of pscs has 4 to 12 percent clay; formed in volcanic ash over colluvium and residuum from metasedimentary rock
Twobit -- moderately deep (20 to 40 inches) to a lithic contact; ashy part of the pscs has 60 to 90 percent glass in the 0.02 to 2.0 mm fraction; loamy-skeletal part of pscs has 18 to 27 percent clay; formed in volcanic ash over colluvium and residuum from metavolcanic rock
GEOGRAPHIC SETTING:
Landform: summits to shoulder slopes and upper back slopes of mountains
Slope gradient: 0 to 60 percent
Parent material: volcaniclastic volcanic ash overlying colluvium
Lithology: Mazama ash overlying andesitic basalt
Elevation: 5,200 to 6,200 feet
Climate: cold, wet winters and cool, moist summers
Mean annual precipitation: 23 to 35 inches
Mean annual air temperature: 36 to 39 degrees F
Frost-free period: 25 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS:
Balmcreek: occur on convex summits, shoulder slopes and steep backslopes, 10 to 20 inches to a lithic contact; has influence of volcanic ash; 60 to 75 dry days in summer
Olot: occur at lower elevations and more southerly aspects, 25 to 35 percent clay in lower part of pscs; 45 to 90 dry days in summer
Rebarrow: occur on planar to concave, mid to lower backslopes and swales; very deep (>60 inches); has argillic layer; 19 to 29 percent clay in lower part of pscs
DRAINAGE AND PERMEABILITY:
Drainage: well drained
Permeability: moderately rapid over moderate
USE AND VEGETATION:
Use: watershed, wildlife habitat, timber production and recreation
Native vegetation: grand fir, lodgepole pine, western larch, Douglas fir, longtube twinflower, common princes pine, grouse huckleberry, big huckleberry, sidebells pyrola, white flowered hawkweed, pink wintergreen, blueleaf strawberry, pinegrass and northwestern sedge
Ecological site: Dominant: ABGR/ LIBOL2; others may include ABGR/VASC and PICO(ABGR)/VASC.
DISTRIBUTION AND EXTENT:
MLRA 10; Central Rocky and Blue Mountain Foothills
Distribution: Blue Mountains in Baker, Grant and Union Counties
Extent: small
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wallowa-Whitman National Forests, Oregon, 2012
REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon: 1 to 2 inches (A horizon)
cambic layer:
upper: 2 to 17 inches (Bw horizon)
lower: 25 to 35 inches; (2Bwb horizon)
particle-size control section:
ashy part: 1 to 17 inches; (A and Bw horizons)
loamy-skeletal part: 17 to 35 inches; (2Eb and 2Bwb horizons)
National Cooperative Soil Survey
U.S.A.