LOCATION DRYACHE                 OR

Tentative Series
IRD. AGG/KLM/MPR
02/2025

DRYACHE SERIES

Landscape: Eastern Cascade Mountains
Landform: moraines
Slope: 0 to 50 percent
Parent Material: volcanic ash mixed with ablation till
Mean annual precipitation: around 750 mm
Mean annual air temperature: around 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, glassy, frigid Humic Vitrixerands

TYPICAL PEDON: Dryache ashy sandy loam, forested, on a northeast-facing, 24 percent slope at an elevation of 1243 meters. (Colors for dry soil unless otherwise noted.)

A1--0 to 9 centimeters; ashy sandy loam, very dark grayish brown (10YR 3/2), black (10YR 2/1) moist; weak medium granular structure; friable, nonsticky, nonplastic; many fine and very fine and few medium roots; many very fine irregular pores; 5 percent subrounded gravel; neutral (pH 6.7); clear smooth boundary

A2--9 to 42 centimeters; ashy sandy loam, dark grayish brown (10YR 4/2), very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many fine and very fine roots; many very fine irregular pores; 8 percent subrounded gravel; neutral (pH 6.9); clear smooth boundary

A3--42 to 70 centimeters; ashy sandy loam, dark grayish brown (10YR 4/2), very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many very fine and common fine roots; many very fine irregular pores; 12 percent subrounded gravel; neutral (pH 7.0); clear smooth boundary

AC--70 to 111 centimeters; extremely cobbly ashy sandy loam, dark grayish brown (10YR 4/2), very dark brown (10YR 2/2) moist; weak medium subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; common very fine and few fine roots; many very fine irregular and few fine tubular pores; 25 percent subrounded gravel and 60 percent subrounded cobbles; neutral (pH 7.0); clear smooth boundary

C--111 to 200 centimeters; extremely cobbly ashy sandy loam, brown (10YR 5/3), very dark grayish brown (10YR 3/2) moist; structureless single grain; loose, loose, nonsticky, nonplastic; few fine roots around fragments; many very fine irregular and few fine tubular pores; 12 percent subrounded gravel and 75 percent subrounded cobbles; neutral (pH 7.0)

TYPE LOCATION: Deschutes County, Oregon; latitude 44.3457590, longitude -121.7301050, datum WGS84 (coordinates determined with a GPS).

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--around 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 45 cm
Depth to till--80 to over 100 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
*Clay content, weighted average: 1 to 5 percent
*Rock fragment content, weighted average: 2 to less than 35 percent

Oi horizon (where present)
*In-lieu of texture--slightly decomposed plant material (needles, twigs)
*Thickness--0-5 cm

A horizons
*Value--1 to 3moist, 3 or 4 dry
*Chroma--1 or 2
*Fine earth texture--ashy sandy loam, ashy loamy sand, ashy fine sandy loam
*Clay--1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--2 to 5 percent at surface, 1 to 3 percent in lower part
*Gravel--0 to 15 percent
*Reaction--pH 6.1 to 7.3 (slightly acid to neutral)
*Thickness--the combined thickness of A horizons is 30 to 70 cm

Bw horizon (where present)
*Value--3 moist, 3 to 5 dry
*Chroma--3
*Fine earth texture--ashy sandy loam, ashy loamy sand, ashy fine sandy loam
*Clay-- 1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--0.50 to 1 percent
*Gravel--0 to 20 percent
*Reaction--pH 6.1 to 7.3 (slightly acid to neutral)
*Thickness--thickness of B horizon is 20 to 40 cm

AC horizon
*Value--2 or 3 moist, 4 dry
*Chroma--2 moist, 2 or 3 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 1.5 percent
*Total rock fragment content--20 to 85 percent
*Gravel--5 to 45 percent
*Cobble--15 to 80 percent
*Reaction--pH 6.6 to 7.3 (neutral)
*Thickness--thickness of AC horizon is 20 to 40 cm

C horizon
*Value--3 to 5 moist, 4 to 6 dry
*Chroma--2 to 4 moist or dry
*Fine earth texture--sandy loam, loamy sand, ashy sandy loam
*Clay--1 to 5 percent
*Sand--55 to 90 percent
*Organic matter--0.2 to 1 percent
*Total rock fragment content--15 to 90 percent
*Gravel--5 to 65 percent
*Cobble--15 to 85 percent
*Stone--0 to 65 percent
*Reaction--pH 6.6 to 7.3 (neutral)
*Thickness--thickness of C horizon is 15 to 90 cm

COMPETING SERIES:
Cobey--dry for 60 to 75 consecutive days following the summer solstice; averages less than 50 percent sand throughout the particle size control section (loam and silt loam texture classes)
Drypok--dry 60 to 90 consecutive days in summer and early fall; 50 to 100 cm to a paralithic contact.
Ermabell--dry 90 to 110 consecutive days following the summer solstice; averages greater than 75 percent sand in the particle size control section (loamy fine sand and coarser); depth to outwash material is greater than 100 cm.
Laidlaw--dry for 90 to 110 consecutive days following the summer solstice; 10 to 30 percent durinodes in the lower horizons; base saturation is 80 to 100 percent by ammonium acetate.
Lundgren--dry for 90 to 110 consecutive days; base saturation is 85 to 100 by ammonium acetate; depth to outwash material is 50 to 100 cm.
Pilotbutte--dry in the moisture control section for 60 to 90 days following the summer solstice; base saturation is 65 to 80 percent by ammonium acetate
Retep--50 to 100 cm to a paralithic contact; dry in all parts of the moisture control section for 60 to 75 consecutive days following the summer solstice.
Suttle--dry in all parts for 60 to 90 consecutive days following the summer solstice; depth to stratified outwash is 50 to 76 cm; particle size control section averages 15 to 35 percent coarse fragments all of which are gravel size cinders.
Trailcreek--50 to 100 cm to a paralithic contact
Wanoga-- 50 to 100 cm to a paralithic or lithic contact
Denoga--dry for 60 to 90 days following the summer solstice; 100 to 200 cm to a lithic contact
Conelicker--dry for 60 to 90 days following the summer solstice; has gravel sized cinders throughout the particle size control section

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 similar geomorphic positions at higher elevations; less than 45 dry days following the summer solstice
Sanagon--occurs on summits and shoulder slopes of moraines; averages greater 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; averages greater than 35 percent fragments in the particle size control section

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--well drained
Saturated hydraulic conductivity (Ksat)-- high to very high throughout

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/CARU (white fir-grand fir/pinegrass)

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 both Dry Creek and Cache Mountain, which are landscape features in close proximity to where the series concept was developed.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
*Particle-size control section--0 to 100 cm
*Umbric epipedon--0 to 42 cm
*Andic soil properties--0 to 200 cm

Laboratory data inferred from geographically associated Belrick series (Pedon#:84P0811) and Lundgren series (Pedon#: 86P0948). 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).

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National Cooperative Soil Survey
U.S.A.