LOCATION SANAGON OR
Tentative Series
IRD. AGG/KLM/MPR
02/2025
SANAGON SERIES
Landscape--Eastern Cascade Mountains
Landform--moraines, glaciated mountain slopes
Slope--0 to 50 percent
Parent Material--volcanic ash mixed with till
Mean annual precipitation-- 750 mm
Mean annual air temperature-- 6 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic
TAXONOMIC CLASS: Ashy-skeletal, glassy, frigid Humic Vitrixerands
TYPICAL PEDON: Sanagon ashy sandy loam, forested, on a west-facing, 4 percent slope at an elevation of 1210 meters. (Colors are for dry soil unless otherwise noted.)
A1--0 to 4 centimeters; very dark gray (10YR 3/1) ashy sandy loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine roots ; many very fine irregular pores; 2 percent gravel; neutral (pH 6.8); abrupt smooth boundary
A2--4 to 18 centimeters; brown (10YR 4/3) ashy sandy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many very fine and fine roots; many very fine irregular pores; 5 percent gravel; neutral (pH 6.9); clear smooth boundary
A3--18 to 46 centimeters; brown (10YR 4/3) cobbly ashy sandy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many very fine and fine and few medium roots ; many very fine irregular pores; 12 percent gravel, 10 percent cobbles, and 2 percent stones; neutral (pH 7.0); clear smooth boundary
Bw--46 to 86 centimeters; brown (10YR 5/3) extremely cobbly ashy sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, very friable,nonsticky, nonplastic; common very fine and fine roots around fragments; many very fine irregular and common fine tubular pores; 15 percent gravel, 65 percent cobbles, and 5 percent stones; neutral (pH 7.0); gradual smooth boundary
C--86 to 200 centimeters; light yellowish brown (10YR 6/4) extremely cobbly ashy sandy loam, dark brown (10YR 3/3) moist; structureless single grain; loose, loose, nonsticky, nonplastic; few fine roots around fragments; common very fine irregular and common fine tubular pores; 30 percent gravel and 55 percent cobbles; neutral (pH 7.0)
TYPE LOCATION: Deschutes County, Oregon; Latitude 44.3595120, Longitude -121.7336630, datum WGS84 (coordinates determine with a GPS).
RANGE IN CHARACTERISTICS:
Mean annual soil temperature-- 7 degrees C
Soil Moisture--usually moist in winter and spring, dry in the moisture control section for 45 to 60 days in the 4 months following the summer solstice
Thickness of umbric epipedon--18 to 46 cm
Thickiness of cambic horizon--15 to 40 cm
Depth to till--45 to 80 cm
Reaction--pH 6.1 to 7.3 (slightly acid to neutral)
Thickness of surface ash influenced layers--90 to over 100 cm
Estimated properties of layers influenced by volcanic ash
*Ammonium oxalate extractable Al + Fe--0.4 to 1.0 percent
*0.02 to 2.0 mm fraction--50 to 90 percent
*Volcanic glass in the 0.02 to 2.0 mm fraction--50 to 80 percent
*P retention--40 to 70 percent
*1500 kPa water retention--less than 15 percent
Particle-size control section: mineral surface to 100 cm below mineral surface
*Clay content, weighted average: 1 to 5 percent
*Rock fragment content, weighted average: 35 to 85 percent
Oi horizon (where present)
*Thickness--0 to 5 cm
A1 horizon
*Value--2 moist, 3 dry
*Chroma--1 or 2
*Fine earth texture--ashy sandy loam, ashy loamy sand
*Clay--1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--2 to 5 percent
*Gravel--2 to 10 percent
*Reaction--pH 6.1 to 6.5 (slightly acid)
*Thickness--thickness of A1 horizon is 4 to 15 cm
A2 horizon
*Value--2 moist, 3 or 4 dry
*Chroma--2 moist, 3 dry
*Fine earth texture--ashy sandy loam, ashy loamy sand
*Clay--1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--1 to 3 percent
*Gravel--0 to 10 percent
*Reaction--pH 6.1 to 7.3 (slightly acid to neutral)
*Thickness--thickness of A2 horizon is 10 to 20 cm
A3 horizon
*Fine earth texture--ashy sandy loam, ashy loamy sand
*Clay--1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--1 to 2 percent
*Total rock fragment content--20 to 55 percent
*Gravel--10 to 30 percent
*Cobble--10 to 20 percent
*Stone--0 to 5 percent
*Reaction-- pH 6.1 to 7.3 (slightly acid to neutral)
*Thickness--thickness of A3 horizon is 15 to 30 cm
Bw horizon
*Value--2 to 3 moist, 3 to 5 dry
*Chroma--2 to 4 moist, 3 to 6 dry
*Fine earth texture--ashy sandy loam, ashy loamy sand
*Clay--1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--0.5 to 1 percent
*Total rock fragment content--20 to 89 percent
*Gravel--10 to 50 percent
*Cobble--10 to 65 percent
*Stone-0 to 40 percent
*Reaction--pH 6.6 to 7.3 (neutral)
*Thickness--thickness of Bw horizon is 15 to 30 cm
C horizon
*Value--3 to 5 moist, 4 to 6 dry
*Chroma--2 to 4 moist or dry
*Fine earth texture--ashy sandy loam, ashy loamy sand, sandy loam, loamy sand
*Clay--1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--0.2 to 0.8 percent
*Total rock fragment content--60 to 89 percent
*Gravel--20 to 30 percent
*Cobble--40 to 55 percent
*Stone--0 to 4 percent
*Reaction--pH 6.6 to 7.3 (neutral)
*Thickness--thickness of C horizon is 15 to 30 cm
COMPETING SERIES:
Fryrear,
Silentcone--50 to 100 cm to to a lithic contact; dry for more than 90 days following the summer solstice
Pipp--100 to 150 cm to a lithic contact; greater than 35 percent rock fragments in the upper horizons
Summertown--50 to 100 cm to a densic contact
Yapoah--greater than 35 percent rock fragments in the upper horizons of the particle size control section; dry for 60 to 90 days following the summer solstice
GEOGRAPHIC SETTING:
Elevation--990 to 1700 meters
Slope--0 to 50 percent
Climate--cool, wet winters and warm, dry summers
Mean annual precipitation--510 to 1000 mm
Mean annual air temperature--5 to 7 degress C
Frost-free period--50 to 80 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Wetache--occurs on backslopes of moraines; less than 45 dry days following the summer solstice
Dryache--occurs on the downwasted portions of moraines; less than 35 percent fragments in the particle size control section
Lundgren--occurs on outwash plains; greater than 90 dry days following the summer solstice
Skelwa--occurs on outwash plains
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--well drained
Saturated hydraulic conductivity (Ksat)--high to very high in all horizons
USE AND VEGETATION:
Use-- timber production, wildlife habitat, recreation
Vegetation-- grand fir, white fir, Douglas-fir, ponderosa pine, snowbrush ceanothus, greenleaf manzanita, golden chinquapin, long-stolon sedge, pinegrass, princes pine, Idaho fescue, western needlegrass, brackenfern, and bottlebrush squirreltail
Typical USFS Plant Association--ABCO-ABGR/CAIN4 (white fir-grand fir/long-stolen sedge)
DISTRIBUTION AND EXTENT:
East slopes of the Cascade Mountains in central Oregon; MLRA 6; minor extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE:Bozeman, Montana
SERIES PROPOSED:
Deschutes County, Deschutes National Forest, Oregon 2023; the name is derived from the nearby Santiam wagon road. This is a historic feature that's also recognized as a local landmark.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
*Particle-size control section--0 to 100 cm
*Umbric epipedon--0 to 46 cm
*Andic soil properties--0 to 200 cm
*Cambic horizon--46 to 86 cm
Laboratory data for the ash mantle is from lab pedon number 84P0811 (Belrick) and 86P0948 (Lundgren). This data is available from the NRCS-NSSC-Kellogg Soil Survey Laboratory, Lincoln, Nebraska. The U.S. Forest Service's "Soil Resource Inventory" data from landtypes 22 and 33 was also used for comparison of soil physical and chemical properties.
The volcanic ash deposit is from the eruption of Mt. Mazama (7.7 kya). There may be some areas with additional deposits from the Sand Mountain eruption (between 3 and 4 kya).
National Cooperative Soil Survey
U.S.A.