LOCATION BLOWOUT OR
Tentative Series
JGM/MPR
12/2024
BLOWOUT SERIES
Landscape--western Cascade mountains
Landform--complex landslides
Slope--0 to 15 percent
Parent material--colluvium derived from volcanic rocks mixed with volcanic ash over residuum weathered from tuff
Mean annual precipitation--about 2600 mm
Mean annual air temperature--about 6 degrees C
Depth class--very deep
Drainage class--moderately well drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--aquic
TAXONOMIC CLASS: Medial over loamy, amorphic over isotic Aquic Haplocryands
TYPICAL PEDON: Blowout medial loam on a forested slope of 35 percent with an elevation of 1250 m
Oi--0 to 3 cm; slightly decomposed plant material; clear smooth boundary
Oe--3 to 8 cm; moderately decomposed plant material; abrupt wavy boundary
A1--8 to 12 cm; medial loam, very dark grayish brown (10YR 3/2) dry, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, fine, and coarse and many medium roots; common fine and many very fine tubular pores; 2 percent gravel; strongly acid (pH 5.1); abrupt wavy boundary
A2--12 to 40 cm; medial loam, brown (10YR 4/3) dry, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very friable, nonsticky and slightly plastic; few fine and common very fine, medium, and coarse roots; common fine and many very fine tubular pores; 2 percent tuff paragravel, 2 percent gravel, and 1 percent cobbles; strongly acid (pH 5.3); clear irregular boundary
A3--40 to 85 cm; medial loam, brown (10YR 4/3) dry, very dark grayish brown (10YR 3/2) moist; moderate very fine granular structure; soft, very friable, nonsticky and slightly plastic; few fine and common very fine, medium, and coarse roots; few fine and common very fine tubular pores; 2 percent tuff paragravel, 2 percent gravel, and 1 percent cobbles; moderately acid (pH 5.6); abrupt wavy boundary
2Bw1--85 to 125 cm; loam, light olive brown (2.5Y 5/4) dry, dark yellowish brown (10YR 4/4) moist; moderate coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common medium and few very fine and coarse roots; common very fine tubular pores; 2 percent medium irregular iron-manganese masses, brownish yellow (10YR 6/6) dry; 3 percent tuff paragravel, 1 percent gravel, and 1 percent cobbles; strongly acid (pH 5.4); gradual wavy boundary
2Bw2--125 to 150 cm; clay loam, light olive brown (2.5Y 5/4) dry, olive brown (2.5Y 4/3) moist; weak coarse subangular blocky structure; moderately hard, friable, slightly sticky and slightly plastic; few very fine roots; 2 percent medium irregular iron-manganese masses, brownish yellow (10YR 6/6) dry; 8 percent tuff paragravel, 3 percent gravel, and 1 percent cobbles; moderately acid (pH 5.6)
TYPE LOCATION: Linn County, Oregon, approximately 3.5 km west of Pinnacle Peak, in Willamette National Forest; 750 m north and 420 m east of the southwest corner of section 23, T. 11 S., R. 5 E., Willamette Meridian; latitude 44.6026260, longitude -122.1692250, datum WGS 84 (coordinates determined with a GPS)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4 to 6 degrees C
Depth to base of umbric epipedon--50 to 100 cm below mineral soil surface
Depth to redoximorphic features--50 to 100 cm below mineral soil surface
Thickness of andic soil properties--50 to 100 cm
Estimated properties of layers with andic soil properties
*Ammonium oxalate extractable Al plus 1/2 Fe--2 to 4 percent
*Particles 0.02 to 2.0-mm--greater than 30 percent of the fine-earth fraction
*Volcanic glass content in 0.02- to 2.0-mm fraction--5 to 30 percent
*15-bar water tension--30 to 70 percent (undried samples), greater than 15 percent (dried samples)
*Phosphate retention--85 to 100 percent
*1/3-bar bulk density--0.6 to 0.9 g/cm3
*Organic carbon content (weighted average)--less than 6 percent
O horizons
*Composition--slightly to moderately decomposed plant material
*Combined thickness--0 to 10 cm
A horizons
*Value--2 or 3 moist, 3 to 5 dry
*Chroma--1 to 3 moist or dry
*Fine-earth texture--medial loam, medial silt loam
*Clay content--15 to 27 percent
*Total fragment content--0 to 35 percent
*Gravel content--0 to 30 percent
*Paragravel content--0 to 10 percent
*Cobble content--0 to 5 percent
*Reaction--pH 5.1 to 6.0
*Combined thickness--50 to 100 cm
2Bw horizons
*Hue--10YR, 7.5YR, 2.5Y
*Value--4 to 6 moist, 5 to 8 dry
*Chroma--2 to 4 moist or dry
*Fine-earth texture--loam, clay loam, silt loam
*Clay content--18 to 35 percent
*Total fragment content--0 to 35 percent
*Gravel content--0 to 15 percent
*Paragravel content--0 to 30 percent
*Cobble content--0 to 5 percent
*Reaction--pH 5.1 to 6.0
COMPETING SERIES:
Metervik--mean annual soil temperature ranges from 0 to 2 degrees C; averages 5 to 15 percent clay in the particle-size control section
GEOGRAPHIC SETTING:
Elevation--980 to 1525 m
Climate--cold, wet winters; mild, dry summers
Mean annual precipitation--1500 to 3600 mm
Mean annual air temperature--5 to 7 degrees C
Frost-free period--60 to 105 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Icecap--50 to 100 cm to lithic contact; located in convex positions on mountain slopes and mountaintops
Idanha--averages greater than 35 percent rock fragments in the particle-size control section; located on mountain slopes
Longbow--greater than 150 cm to aquic conditions; located on complex landslides and mountaintops
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--moderately well drained
Saturation in normal years--below a depth of 50 to 100 cm in April through June
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--moderately high or high
USE AND VEGETATION:
Use--timber production, water supply, wildlife habitat, recreation
Potential natural vegetation--Pacific silver fir, Douglas-fir, western hemlock, Alaska huckleberry, thinleaf huckleberry, bunchberry dogwood, bride's bonnet, threeleaf foamflower
DISTRIBUTION AND EXTENT: Western Cascade Mountains, Oregon; MLRA 3; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Willamette National Forest, Linn County, Oregon; 2016; name from Blowout Creek in Willamette National Forest
REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 8 to 108 cm
*Umbric epipedon--zone from 8 to 85 cm
*Cambic horizon--zone from 85 to 150 cm
*Andic soil properties--zone from 8 to 85 cm
*Volcanic glass--zone from 8 to 85 cm
*Redoximorphic concentrations--zone from 85 to 150 cm
*Aquic conditions--zone from 85 to 150 cm
*Endosaturation--zone from 85 to 150 cm
*Depth to lithologic discontinuity--85 cm
8/2023--layers with andic soil properties meet criteria 2 (no ash required) and 3 for andic soil properties in the 13th edition of Keys to Soil Taxonomy.
ADDITIONAL DATA: Type location site ID--2014OR043823
National Cooperative Soil Survey
U.S.A.