LOCATION LEMISH OR
Tentative Series
IRD. AGG/DEW
08/2025
LEMISH SERIES
Landscape--Eastern Cascade mountains
Landform--moraines or glaciated mountain slopes
Slope--5 to 50 percent slopes
Parent Material--volcanic ash mixed with till and/or colluvium derived from till
Mean annual precipitation--980 mm
Mean annual air temperature--3.5 degrees C
Depth class--very deep
Drainage class--somewhat excessively drained
Soil moisture regime--xeric
Soil temperature regime--cryic
Soil moisture subclass--typic
TAXONOMIC CLASS: Ashy-skeletal, glassy Xeric Vitricryands
TYPICAL PEDON: Lemish ashy loamy sand, forested, on a 38 percent slope at an elevation of 1446 meters. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 4 centimeters; slightly decomposed plant material; strongly acid (pH 5.5); abrupt wavy boundary.
A--4 to 10 centimeters; brown (10YR 4/3) ashy loamy sand, dark brown (10YR 3/3) moist; weak coarse granular structure; soft, very friable, nonsticky, nonplastic; many very fine and common fine roots throughout; many fine irregular pores; 10 percent stones; slightly acid (pH 6.3); abrupt smooth boundary.
AB--10 to 34 centimeters; dark yellowish brown (10YR 4/4) gravelly ashy loamy coarse sand, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure parts to single grain; soft, very friable, nonsticky, nonplastic; few very fine, common medium, and many fine roots throughout and few coarse roots in the top of horizon; many fine irregular pores; 18 percent gravel, 5 percent cobbles, and 2 percent stones; slightly acid (pH 6.5); clear smooth boundary.
Bw1--34 to 57 centimeters; yellowish brown (10YR 5/4) paragravelly loamy coarse sand, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure parts to single grain; soft, very friable, nonsticky, nonplastic; common medium and many fine roots throughout; many fine irregular pores; 10 percent paragravel pumice fragments, 8 percent cobbles, and 2 percent stones; neutral (pH 6.7); gradual smooth boundary.
Bw2--57 to 84 centimeters; brown (10YR 5/3) very cobbly ashy loamy coarse sand, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure parts to single grain; loose, nonsticky, nonplastic; common medium and fine roots around fragments; few medium irregular pores; 4 percent gravel and 38 percent cobbles; neutral (pH 6.8); clear smooth boundary.
C--84 to 152 centimeters; brown (10YR 5/3) extremely cobbly ashy loamy sand, dark yellowish brown (10YR 3/4) moist; single grain; loose, nonsticky, nonplastic; few medium roots around fragments; few medium irregular pores; 2 percent gravel, 45 percent cobbles, and 20 percent stones; neutral (pH 7.0).
TYPE LOCATION: Deschutes County, Oregon; SW 1/4, SE 1/4 of section 35, T. 20 S, R. 7 E; Latitude 43.7898920, Longitude -121.8529280, datum WGS84 (coordinates determine with a GPS).
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--5.2 to 7.2 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 ash influenced layers--over 100 cm
Estimated properties of layers influenced by volcanic ash
Ammonium oxalate extractable Al + Fe--0.4 to 1.0 percent
1500 kPa water content (air dry)--3 to 12 percent
0.02 to 2.0 mm fraction--55 to 90 percent
Volcanic glass in the 0.02 to 2.0 mm fraction--40 to 80 percent
P retention--25 to 50 percent
Particle-size control section: mineral soil surface to 100 cm below the soil surface
Clay content, weighted average--1 to 8 percent
Rock fragment content, weighted average--35 to 85 percent
A horizons
Hue--10YR
Value--3 to 5
Chroma--3 to 6
Fine earth texture--ashy loamy sand, ashy loamy coarse sand or ashy sandy loam
Clay content--1 to 8 percent
Sand content--55 to 90 percent
Organic matter--0.50 to 2 percent
Total rock fragment content--0 to 45 percent
Pumice paragravel--0 to 10 percent
Gravel--0 to 35 percent
Cobble--0 to 35 percent
Stone--0 to 10 percent
Reaction--6.1 to 7.3 (slightly acid to neutral)
Thickness--5 to 25 cm
Bw horizon(s)
Hue--10YR
Value--3 to 7
Chroma--3 to 6
Fine earth texture--ashy loamy sand, ashy loamy coarse sand, ashy sandy loam
Clay content--1 to 8 percent
Sand content--55 to 90 percent
Organic matter--0.10 to 0.50 percent
Total rock fragment content--20 to 85 percent
Pumice paragravel--0 to 10 percent
Gravel--0 to 45 percent
Cobble--5 to 50 percent
Stone--0 to 20 percent
Reaction--6.1 to 7.3 (slightly acid to neutral)
Thickness--23 to 27 cm
C horizon
Hue--10YR
Value--3 to 8
Chroma--3 to 8
Fine earth texture--ashy loamy sand, ashy loamy coarse sand or ashy sandy loam
Clay content--1 to 8 percent
Sand content--55 to 90 percent
Organic matter--0 to 0.25 percent
Total rock fragment content--40 to 85 percent
Pumice paragravel--0 to 10 percent
Gravel--0 to 45 percent
Cobble--35 to 65 percent
Stone--10 to 35 percent
Reaction--6.1 to 7.3 (slightly acid to neutral)
Thickness--50 to 80 cm
COMPETING SERIES:
Azwell--50 to 100 cm to lithic contact; has a cambic horizon
Bamber--100 to 150 cm to lithic contact; has an albic horizon
Fears--has a cambic horizon; does not allow loamy sand or loamy coarse sand in the particle-size control section
Gurlidawg--50 to 100 cm to paralithic contact; averages 10 to 18 percent clay in the particle-size control section
Hallihan--has a cambic horizon; does not allow loamy sand or loamy coarse sand in the particle-size control section
Madrak--50 to 100 cm to lithic contact; has a cambic horizon
Shadowlake--100 to 150 cm to densic contact; has a cambic horizon
Terence--has a cambic horizon; does not allow loamy sand or loamy coarse sand in the particle-size control section
Tiptop--has a cambic horizon; does not allow loamy sand or loamy coarse sand in the particle-size control section
Wuksi--hues redder than 10YR; has a lithological discontinuity
GEOGRAPHIC SETTING:
Elevation--1325 to 2000 m
Climate--cold, wet winters and cool, dry summers
Mean annual precipitation--640 to 1100 mm
Mean annual air temperature--2.5 to 5.2 degrees C
Frost-free period--20 to 50 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Shroyton--occurs on lower elevation mountain slopes; has a mollic epipedon; less than 35 percent fragments in the particle-size control section
Yapoah--occurs on lower elevation mountain slopes; has a mollic epipedon
Shukash--occurs on lava plains; recognizes a buried soil with the particle-size control section
Steiger--occurs on lava plains, buttes, and cinder cones; less than 35 percent fragments in the particle-size control section
Norwicki--occurs on lower elevation lava flows and plains; 50 to 100 cm to lithic contact
Castlecrest--occurs on mountain flanks and buttes; less than 35 percent fragments in the particle-size control section; soil moisture control section dry for less than 45 dry days following the summer solstice (udic soil moisture regime)
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--somewhat excessively drained
Saturated hydraulic conductivity (Ksat)--high to very high
USE AND VEGETATION:
Use--timber production, wildlife habitat
Vegetation--ponderosa pine, lodgepole pine, Douglas fir, white fir, greenleaf manzanita, wax currant, snowbrush ceanothus, long-stolon sedge, pipsissewa, western rattlesnake plantain
Typical USFS Plant Association--ABCO-ABGR/CHUM (white fir-grand fir/pipsissewa)
DISTRIBUTION AND EXTENT:
East slopes of the Cascade Mountains in central Oregon; MLRA 06; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED:
Deschutes County, Deschutes National Forest, Oregon 2025; name derived from Lemish Butte in the Deschutes National Forest
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Particle-size control section--4 to 104 cm (A, AB, Bw1, Bw2, and part of the C horizon)
Ochric epipedon--4 to 34 cm (A and AB horizons)
Andic soil properties--4 to 152 cm (A, AB, Bw1, Bw2, and C horizons)
National Cooperative Soil Survey
U.S.A.