LOCATION YAWHEE                  OR

Established Series
Rev. RPO/AON/RWL/CEG
02/2025

YAWHEE SERIES

Landscape--mountains
Landform--volcanic cones, escarpments, cuestas
Slope--3 to 40 percent
Parent material--sandy colluvium derived from volcanic rock and/or from coarse pumiceous volcanic ash and pumice parafragments over loamy colluvium derived from volcanic rock and/or tephra
Mean annual precipitation--about 560 mm
Mean annual air temperature--about 6.1 degrees C
Depth class--very deep
Drainage class--somewhat excessively drained
Soil moisture regime--udic
Soil temperature regime--frigid
Soil moisture subclass--typic

TAXONOMIC CLASS: Ashy-skeletal over loamy-skeletal, amorphic over isotic, frigid Alfic Udivitrands

TYPICAL PEDON: Yawhee gravelly ashy coarse sandy loam on a forested volcanic cone with a slope of 15 percent and an elevation of 1987.5 m.

Oi--0 to 3 cm; slightly decomposed plant material consisting of a loose mat of pine and fir needles.

A1--3 to 8 cm; gravelly ashy coarse sandy loam, dark grayish brown (10YR 4/2) dry, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and nonplastic; many roots; many fine pores; 15 percent gravel, 5 percent stones; slightly acid (pH 6.4); clear wavy boundary.

A2--8 to 35 cm; very cobbly ashy coarse sandy loam, grayish brown (10YR 5/2) dry, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many roots; many very fine pores; 20 percent gravel, 15 percent cobbles, and 5 percent stones; slightly acid (pH 6.4); clear wavy boundary.

C--35 to 74 cm; very cobbly ashy loamy coarse sand, brown (10YR 5/3) dry, dark yellowish brown (10YR 3/4) moist; massive; soft, very friable; nonsticky and nonplastic; many roots; many very fine pores; 25 percent gravel, 15 percent cobbles, and 10 percent stones; slightly acid (pH 6.3); clear wavy boundary.

2Ab--74 to 97 cm; very gravelly ashy fine sandy loam, brown (10YR 4/3) dry, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many roots; many very fine pores; 35 percent gravel, 5 percent cobbles, and 5 percent stones; slightly acid (pH 6.1); clear wavy boundary.

2Btb1--97 to 130 inches; very gravelly ashy loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; moderate fine and medium angular blocky structure; hard, firm, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; few faint clay films on peds; 55 percent gravel and 4 percent cobbles; slightly acid (pH 6.1); clear smooth boundary.

2Btb2--130 to 155 cm; extremely gravelly ashy loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; moderate fine and medium angular blocky structure; hard, firm, slightly sticky and slightly plastic; few very fine and fine roots; common very fine pores; few faint clay films on peds; 55 percent gravel, 5 percent cobbles, and 5 percent stones; slightly acid (pH 6.3).

TYPE LOCATION: Klamath County, Oregon; 775.7 m west and 274.3 m north of the southeast corner, sec. 19, T.36S., R.9E., Willamette Meridian; Swan Lake Point, Oregon USGS quadrangle. Latitude 42.431363 degrees north, longitude 121.692169 degrees west, datum WGS84 (coordinates derived from legal description)

RANGE IN CHARACTERISTICS:

*Soil Temperature: frigid regime
*Mean annual soil temperature-- 3.3 to 7.8 degrees C
*Mean summer soil temperature-- 4.4 to 10.6 degrees C
*Mean winter soil temperature-- -0.5 to 3.9 degrees C
*Moisture control section--20 to 60 cm; not dry in any part for as long as 90 days in normal years; dry in all parts for 30 to 45 consecutive days in August, September or October
*Rock fragments--pumice paragravel in the upper part of the profile; andesite paragravel in the lower part of the profile; hard lava or andesite gravel, cobbles and stones
*Umbric epipedon--25 to 48 cm thick
*Lithologic discontinuity, depth below mineral soil surface--36 to 89 cm

Particle-size control section
*Rock fragment content, upper part--35 to 70 percent
*Rock fragment content, lower part--35 to 80 percent
*Pararock fragment content, upper part--0 to 10 percent
*Pararock fragment content, lower part--0 to 15 percent

Estimated properties, upper part of the profile
*Ammonium oxalate extractable Al plus 1/2 Fe--0.4 to 2.0 percent
*.02- to 2.0-mm fraction--60 to 90 percent
*medium to very coarse sand in the .02 to 2.0 mm fraction--greater than 50 percent
*P retention--25 to 50
*Volcanic glass content--15 to 100 percent
*Moist bulk density--0.7 to 1.0 g/cm3
*1/3-bar bulk density--0.75 to 0.9 g/cm3
*1500 kPa water (air-dried samples)--3 to 12 percent

A horizons (and AB horizons, where present)
*Hue--5YR, 7.5YR, or 10YR moist, 7.5YR or 10YR dry
*Value--2 to 3 moist, 3 to 5 dry; some coarse and very coarse sand grains are 4 moist, 6 dry
*Chroma--2 or 3 moist, 2 to 4 dry; some coarse and very coarse sand grains are 4 to 6 moist, 4 dry
*Fine-earth texture--ashy coarse sandy loam, ashy loamy coarse sand
*Clay content--1 to 15 percent
*Total content of rock and pararock fragments--20 to 80 percent
*Paragravel content--0 to 5 percent
*Gravel content--10 to 30 percent
*Cobble content--1 to 40 percent
*Stone content--0 to 40 percent
*Boulder content--0 to 25 percent
*Reaction: slightly acid to neutral (pH 6.1 to 7.3)
*Thickness--25 to 48 cm

C horizon (and Bw horizon, where present)
*Hue--5YR, 7.5YR, or 10YR moist, 7.5YR or 10YR dry
*Value--3 or 4 moist, 5 or 6 dry
*Chroma--3 or 4 moist or dry; some coarse and very coarse sand grains are 4 to 6 moist, 4 dry
*Fine-earth texture--ashy coarse sandy loam, ashy loamy sand, ashy loamy coarse sand
*Clay content--1 to 15
*Total content of rock and pararock fragments--35 to 80 percent
*Paragravel content--0 to 5 percent
*Gravel content--15 to 30 percent
*Cobble content--5 to 45 percent
*Stone content--0 to 40 percent
*Boulder content--0 to 25 percent
*Reaction: slightly acid to neutral (pH 6.1 to 7.3)
*Thickness--12 to 46 cm

2Ab horizon (where present)
*Hue--5YR, 7.5YR, or 10YR moist, 7.5YR or 10YR dry
*Value--3 moist, 4 or 5 dry
*Chroma--2 or 3 moist, 3 dry
*Fine-earth texture--ashy loam, ashy fine sandy loam
*Clay content--1 to 15 percent
*Total content of rock and pararock fragments--15 to 80 percent
*Gravel content--0 to 35 percent
*Cobble and stone content--0 to 15 percent
*Boulder content--0 to 25 percent
*Reaction: slightly acid to neutral (pH 6.1 to 7.3)
*Thickness--0 to 38 cm

2Btb horizons
*Hue--5YR, 7.5YR, or 10YR moist, 7.5YR or 10YR dry
*Value--3 moist, 4 or 5 dry
*Chroma--2 to 4 moist, 2 or 3 dry
*Fine-earth texture--ashy clay loam, ashy loam
*Clay content--20 to 30
*Total content of rock and pararock fragments--35 to 80 percent
*Paragravel content--0 to 15 percent
*Gravel content--10 to 55 percent
*Cobble and stone content--5 to 45 percent
*Boulder content--0 to 60 percent

COMPETING SERIES:

Kutcher-- paralithic contact with andesite between 20 and 40 inches from the soil surface; sandy loam textures in the upper part of the profile

GEOGRAPHIC SETTING:
Elevation--1375 to 2210 m
Climate--cold moist winters and cool dry summers
Mean January air temperature-- -3.8 to -2.8 degrees C
Mean July air temperature-- 13.9 to 16.7 degrees C
Mean annual air temperature-- 2.7 to 6.7 degrees C
Mean annual precipitation--508 to 1120 mm
Frost-free period--50 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Swantower--cryic soil temperature regime; scarp slopes and dip slopes on stratovolcanoes; cambic horizon in lower part of profile
Swansprings-- cryic soil temperature regime; dip slopes on stratovolcanoes
Edgewood--scarp slopes and dip slopes on stratovolcanoes; cambic horizon in the lower part of the profile
Nuss--lack andic soil properties in the upper part of the profile; less than 35 percent rock fragments in any part
Ponina--lack andic soil properties in the upper part of the profile; ochric epipedons; clay Bt horizons; duripans at depths of 30 to 50 cm
Royst--lack andic soil properties in the upper part of the profile; very gravelly clay loam and gravelly clay argillic horizons; bedrock at depths of 60 to 100 cm
Woodcock--medial soil textural modifiers (medial-skeletal particle size class)

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat excessively drained
Saturated hydraulic conductivity (Ksat)--high to very high in the upper part and moderately high to high in the lower part

USE AND VEGETATION:
Use--timber production, wildlife habitat, livestock grazing, recreation
Vegetation--ponderosa pine, white fir, Douglas-fir, sugar pine, incense cedar, and understory plants.

DISTRIBUTION AND EXTENT: Olympic and Cascade Mountains, Oregon; MLRA 3; moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED:
Klamath County, Oregon, 1977

REMARKS:
Diagnostic horizons and features in this pedon
*Umbric epipedon--zone from 3 to 32 cm
*Argillic horizon--zone from 97 to 155 cm
*Andic soil properties--zone from 3 to 74 cm
*Volcanic glass--zone from 3 to 155 cm
*Depth to lithologic discontinuity--97 cm
*Particle-size control section--3 to 103 cm (3 to 74 cm ashy-skeletal, 74 to 103 cm loamy-skeletal)

5/2020--Updated mineralogy in taxonomic classfication, surface textural modifier, ashy textural modifiers in lower part, andic soil properties, competing series, geographically associated soils, epipedon type and information on laboratory data. This official series description was also updated according to SSR1 Technical Note 11--Content and Format of Official Series Descriptions (revised 11/6/2017).

ADDITIONAL DATA:
NASIS SITE ID--1977OR035004; NASIS PEDON ID--1977OR035004

KSSL analysis from a different pedon correlated to the Yawhee series, sample number S2005OR683014 (NASIS site ID 05-JFD-14).

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National Cooperative Soil Survey
U.S.A.