LOCATION UFFDA                   OR

Tentative Series
IRD. KBC/BTH/MPR
02/2025

UFFDA SERIES

Landscape--pumice mantled plateaus
Landform--landslides and falls on tephra volcanic fields on southwest facing scarps
Slope--15 to 75 percent
Parent material--sandy colluvium derived from volcanic rocks and coarse pumiceous volcanic ash and pumiceous tephra over loamy colluvium
Mean annual precipitation--about 730 mm
Mean annual air temperature--about 6 degrees C
Depth class--very deep
Drainage class--excessively
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic

TAXONOMIC CLASS: Ashy-skeletal over loamy-skeletal, glassy over isotic, frigid Typic Vitrixerands

TYPICAL PEDON: Uffda gravelly ashy loamy sand, forested, on a soil fall on a tephra field on a scarp with a slope of 20 percent, at an elevation of 1373 m, with surface fragments of 20 percent gravel, 5 percent cobbles, 1 percent stones and 1 percent boulders

Oi--0 to 6 cm; slightly decomposed plant material; abrupt smooth boundary

A--6 to 18 cm; gravelly ashy loamy sand, brown (10YR 5/3) dry, dark yellowish brown (10YR 3/4) moist; moderate medium granular structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine and medium, and few coarse roots; common fine dendritic tubular pores; 30 percent andesite gravel and 12 percent fine pumice paragravel; moderately acid (pH 6.0); gradual smooth boundary

Bw--18 to 42 cm; very gravelly ashy loamy coarse sand, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine to coarse and few very coarse roots; common fine dendritic tubular pores; 36 percent andesite gravel, 12 percent andesite cobbles, and 16 percent fine to medium pumice paragravel; moderately acid (pH 6.0); gradual smooth boundary

BC--42 to 80 cm; very gravelly ashy loamy sand, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine to coarse and few very coarse roots; common fine dendritic tubular pores; 40 percent andesite gravel, 12 percent andesite cobbles, and 16 percent fine to medium pumice paragravel; moderately acid (pH 6.0); abrupt smooth boundary

2Bwb1--80 to 118 cm; very gravelly sandy loam, 90 percent light yellowish brown (10YR 6/4) and 10 percent brownish yellow (10YR 6/6) dry, 90 percent brown (10YR 4/3) and 10 percent dark grayish brown (10YR 4/2) moist; moderate medium and coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine to medium and few coarse and very coarse roots; common very fine and fine dendritic tubular pores; 36 percent andesite gravel, 3 percent andesite cobbles, 5 percent andesite stones; moderately acid (pH 6.0); gradual smooth boundary

2Bwb2--118 to 200 cm; very gravelly sandy loam, light brownish gray (10YR 6/2) dry, dark grayish brown (10YR 4/2) moist; weak medium and coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and medium roots; common fine dendritic tubular pores; 45 percent andesite gravel and 3 percent andesite cobbles; slightly acid (pH 6.5)

TYPE LOCATION: Klamath County, Oregon; about 512 m west and 638 m south of the northwest corner of sec. 11, T.33S., R.7.5E., Willamette Meridian; Fort Klamath, Oregon USGS quadrangle; Latitude 42.7276710 degrees north, longitude 121.9700220 degrees west, datum WGS84 (coordinates derived from GPS unit)

RANGE IN CHARACTERISTICS:

*Soil Temperature--frigid regime
*Mean annual soil temperature-- 6.4 to 8.0 degrees C
*Mean summer soil temperature-- 11.4 to 13.0 degrees C
*Mean winter soil temperature-- 2.5 to 4.1 degrees C
*Moisture control section--30 to 90 cm below the soil surface; dry 45 to 60 consecutive days following the summer solstice
*Rock fragments--pumice paragravel; andesite or basalt gravel
*Depth to loamy-skeletal, buried soil--60 to 90 cm from the mineral soil surface

Particle-size control section
*Clay content--3 to 14 percent
*Rock fragment content--20 to 73 percent
*Pararock fragment content--11 to 58 percent

Estimated properties, horizons and layers above the lithologic discontinuity
*Thickness--60 to 90 cm
*Ammonium oxalate extractable Al plus 1/2 Fe--0.2 to 0.4 percent
*Medium to very coarse sand in the .02 to 2.0 mm fraction--greater than 50 percent
*P retention--25 to 50 percent
*Volcanic glass content--75 to 100 percent
*Moist bulk density--0.7 to 1.0 g/cm3
*1/3-bar bulk density--0.5 to 0.9 g/cm3
*1500 kPa water (air-dried samples)--3 to 12 percent

Oi horizon (where present)
*Thickness--0 to 15 cm

A horizon
*Value--2 to 4 moist, 4 to 6 dry
*Chroma-1 to 4 moist or dry
*Fine-earth texture--ashy loamy sand, ashy loamy coarse sand
*Clay content--3 to 10 percent
*Total content of rock and pararock fragments--35 to 60 percent
*Total content of rock fragments--15 to 34 percent
*Paragravel content--10 to 50 percent
*Gravel content--5 to 34 percent
*Cobble content--0 to 5 percent
*Stone content--0 to 5 percent
*Reaction--moderately acid to neutral (pH 5.6 to 7.3)
*Thickness--3 to 15 cm

Bw horizon
*Hue--10YR or 2.5Y, moist or dry
*Value--3 to 8 moist, 4 to 8 dry
*Chroma--2 to 8 moist, 2 to 6 dry
*Fine-earth texture--ashy loamy sand, ashy loamy coarse sand, ashy coarse sand
*Clay content--0 to 10 percent
*Total content of rock and pararock fragments--30 to 84 percent
*Total content of rock fragments--15 to 75 percent
*Paragravel content--15 to 70 percent
*Gravel content--5 to 50 percent
*Cobble content--0 to 20 percent
*Stone content--0 to 20 percent
*Reaction--moderately acid to neutral (pH 5.6 to 7.3)
*Thickness--20 to 85 cm

BC horizon (where present)
*Hue--10YR or 2.5Y, moist or dry
*Value--4 to 8 moist, 4 to 8 dry
*Chroma--2 to 8 moist or dry
*Fine-earth texture--ashy loamy sand, ashy loamy coarse sand, ashy coarse sand
*Clay content--0 to 10 percent
*Total content of rock and pararock fragments--30 to 100 percent
*Total content of rock fragments--15 to 75 percent
*Paragravel content--15 to 85 percent
*Gravel content--5 to 50 percent
*Cobble content--10 to 20 percent
*Stone content--0 to 20 percent
*Reaction--moderately acid to neutral (pH 5.6 to 7.3)
*Thickness--0 to 65 cm

2Bwb horizons
*Value--3 to 6 moist, 4 to 7 dry
*Chroma--2 to 6 moist or dry
*Fine-earth texture--loam, sandy loam
*Clay content--10 to 25 percent
*Total content of rock and pararock fragments--35 to 85 percent
*Total content of rock fragments--35 to 85 percent
*Paragravel content--0 to 10 percent
*Gravel content--20 to 50 percent
*Cobble content--0 to 10 percent
*Stone content--0 to 20 percent
*Boulder content--0 to 20 percent
*Reaction--moderately acid to neutral (pH 5.6 to 7.3)

COMPETING SERIES:
Stien--aniso particle size class; 30 to 65 percent volcanic glass; 1 to 3 percent ammonium oxalate extractable Al plus 1/2 Fe; parent materials include glacial outwash and drift; ashy silt loam textures in the surface; ashy-skeletal materials have less than 50 percent medium to very coarse sand in the .02 to 2.0 mm fraction

GEOGRAPHIC SETTING:
Elevation--1270 to 1600 m
Climate--cold wet winters and cool dry summers
Mean annual air temperature--5.0 to 7.2 degrees C
Mean annual precipitation--460 to 1000 mm
Frost-free period--40 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Lapine--similar landforms; cryic soil temperature regime
Steiger--similar landforms; cryic temperature regime; less than 35 percent pumice paragravel in the particle size control section
Mousetails--similar landforms; ashy-pumiceous particle size class

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--excessively
Saturated hydraulic conductivity (Ksat)--moderately high to high

USE AND VEGETATION:
Use--timber production, wildlife habitat, recreation
Vegetation--incense cedar, sugar pine, ponderosa pine, Douglas fir, serviceberry, Greenleaf manzanita, prostrate ceanothus, tall Oregongrape, golden chinquapin, snowbrush, common prince's pine, antelope bitterbrush, dwarf rose, woodland strawberry, squirrel tail, western needlegrass, longstolon sedge

DISTRIBUTION AND EXTENT: Cascade Mountains, Eastern Slope; MLRA 6; small extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES PROPOSED:
Klamath County, Northern Part, Oregon, 2020
Origin of the name--the name is coined

REMARKS:
Diagnostic horizons and features in this pedon
*Particle size control section--6 to 106 cm
*Ochric epipedon
*Volcanic glass--6 to 80 cm
*Andic soil properties--6 to 80 cm
*Lithologic discontinuity--80 cm
*Strongly contrasting particle size class--80 cm

ADDITIONAL DATA:
NASIS SITE ID--2019OR035059; NASIS PEDON ID--2019OR035059

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National Cooperative Soil Survey
U.S.A.