LOCATION ELBOWCREEK OR
Established Series
Rev. RLW/KMS
11/2018
ELBOWCREEK SERIES
Landscape--mountains
Landform--plateaus
Slope--0 to 15 percent
Parent material--thick mantle of volcanic ash over lacustrine deposits
Mean annual precipitation--about 730 mm
Mean annual air temperature--about 6 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--frigid
Soil moisture subclass--typic
TAXONOMIC CLASS: Ashy over loamy, amorphic over isotic, frigid Alfic Udivitrands
TYPICAL PEDON: Elbowcreek ashy silt loam, forested
Oi--0 to 3 cm
A--3 to 15 cm; ashy silt loam, brown (7.5YR 5/3) dry, dark brown (7.5YR 3/3) moist; weak medium subangular blocky structure parting to weak fine subangular blocky; soft, friable, nonsticky and nonplastic; common very fine and fine roots throughout; common very fine and fine irregular pores; 1 percent gravel; neutral (pH 6.7); clear wavy boundary
Bw1--15 to 43 cm; ashy silt loam, light brown (7.5YR 6/3) dry, brown (7.5YR 4/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, fine, and medium roots throughout; common very fine irregular pores; 1 percent gravel; slightly acid (pH 6.5); clear wavy boundary
Bw2--43 to 58 cm; ashy silt loam, light yellowish brown (10YR 6/4) dry, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, fine, medium, and coarse roots throughout; common very fine interstitial pores; 1 percent gravel; slightly acid (pH 6.4); abrupt wavy boundary
2Bwb--58 to 76 cm; silt loam, light brown (7.5YR 6/3) dry, brown (7.5YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine, and medium roots throughout; common very fine interstitial and tubular pores; 3 percent gravel; slightly acid (pH 6.1); clear wavy boundary
2Btb1--76 to 119 cm; silt loam, pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; moderate medium subangular blocky structure; moderately hard, friable, moderately sticky and moderately plastic; common fine and medium roots throughout; common very fine tubular and irregular pores; 1 percent faint clay bodies on faces of peds; slightly acid (pH 6.1); clear smooth boundary
2Btb2--119 to 386 cm; silty clay loam, pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; moderate medium angular blocky structure; moderately hard, firm, moderately sticky and moderately plastic; common fine roots between peds; common very fine tubular and irregular pores; 15 percent distinct clay bodies on faces of peds; slightly acid (pH 6.1)
TYPE LOCATION: Wallowa County, Oregon; about 675 m west and 440 m south of the northeast corner of section 1, T. 5 N., R. 41 E., latitude 45.9444695, longitude -117.6340942, datum WGS 84 (source of coordinates unknown but most likely determined from a GPS)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4 to 8 degrees C
Soil moisture--dry 30 to 45 consecutive days following summer solstice
Layers influenced by volcanic ash--36 to 75 cm below mineral soil surface
Estimated properties of layers influenced by volcanic ash
*Ammonium oxalate extractable Al + 1/2 Fe--0.4 to 1.0 percent
*Phosphate retention--25 to 50 percent
*15-bar water retention--less than 30 percent (undried samples), 5 to 10 percent (dried samples)
*0.02- to 2.0-mm fraction--60 to 80 percent
*Glass content in 0.02- to 2.0-mm fraction--25 to 45 percent
Particle-size control section
*Upper part--4 to 8 percent clay; 1 percent total rock fragments
*Lower part--15 to 30 percent clay; 0 to 5 percent total rock fragments
A horizon
Fine-earth texture--ashy silt loam
Clay content--4 to 9 percent
Sand content--30 to 40 percent
Organic matter content--1.0 to 4.5 percent
Total rock fragment content--1 percent
Gravel content--1 percent
Reaction--6.1 to 7.3
Bw horizon
Fine-earth texture--ashy silt loam
Clay content--5 to 8 percent
Sand content--30 to 40 percent
Organic matter content--0.5 to 2.5 percent
Total rock fragment content--1 percent
Gravel content--1 percent
Reaction--6.1 to 7.3
2Bwb horizon
Fine-earth texture--silt loam
Clay content--15 to 19 percent
Sand content--3 to 15 percent
Total rock fragment content--1 to 5 percent
Gravel content--1 to 5 percent
Organic matter content--0 to 2 percent
Reaction--6.1 to 7.3
2Btb horizon
Fine-earth texture--silt loam, silty clay loam
Clay content--18 to 28 percent
Sand content--5 to 10 percent
Total rock fragment content--0 to 10 percent
Gravel content--0 to 10 percent
Organic matter content--0 to 2 percent
Reaction--6.1 to 7.3
COMPETING SERIES:
Dowper--0 to 75 percent pararock fragments in substratum
Jacot--loamy sand and sand in substratum
Mackatie--paralithic contact at a depth of 100 to 150 cm (deep)
Secunda--loamy sand and sand in substratum
Tamara--as much as 30 percent rock fragments in substratum
Tomodo--fragic properties in substratum
Turpentine--paralithic contact at a depth of 100 to 150 cm (deep)
GEOGRAPHIC SETTING:
Elevation--850 to 1520 m
Climate--cool, wet winters; hot, dry summers
Mean annual precipitation--530 to 990 mm
Mean annual temperature--5 to 7 degrees C
Frost-free season--40 to 150 days
GEOGRAPHICALLY ASSOCIATED SOILS: None given
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Saturation during normal years--none
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--moderately high
USE AND VEGETATION:
Use--timber production, wildlife habitat, water supply, livestock grazing
Potential natural vegetation--grand fir, northern twinflower, big huckleberry, Engelmann spruce, Douglas-fir, queencup bead lily, pathfinder, heartleaf arnica, starry false Solomon's seal, darkwoods violet, western meadow-rue, prince's pine, western larch, Utah honeysuckle, sweetcicely, baldhip rose, Columbia brome, Ross' sedge, roughfruit fairybells, woodland strawberry
DISTRIBUTION AND EXTENT: Blue Mountains in eastern Oregon; MLRA 10; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wallowa-Whitman National Forest, Oregon; 2018
REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Argillic horizon--zone from 76 to 386 cm
*Volcanic glass--zone from 3 to 58 cm
*Andic soil properties--zone from 3 to 58 cm
*Particle-size control section--zone from 3 to 103 cm
*Depth to lithologic discontinuity--58 cm
National Cooperative Soil Survey
U.S.A.