LOCATION HUDSPINE                OR

Tentative Series
KLM/JRD
02/2025

HUDSPINE SERIES

The Hudspine Series consists of moderately deep to duripan, well drained soils that formed in volcanic ash over residuum from fanglomerate. Hudspine soils are on pediments, and fan remnants. Slopes are 0 to 45 percent. Mean annual precipitation is about 380 mm and the mean annual temperature is 7 degrees C.

Landscape--plateaus
Landform--fan remnants or pediments
Slope--0 to 45 percent
Parent Material--thick mantel of volcanic ash over residuum derived from fanglomerate
Mean annual precipitation--about 380 mm
Mean annual air temperature--about 7 degrees C
Depth class--moderately deep to duripan
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic

TAXONOMIC CLASS: Ashy over clayey-skeletal, glassy over smectitic, frigid Alfic Vitrixerands

TYPICAL PEDON: Hudspine ashy sandy loam - woodland, on a two percent slope at an elevation of 1400 meters. (Colors are for moist soil unless otherwise noted.)

Oi -- 0 to 3 cm; slightly decomposed twigs, and needls; clear smooth boundary.

A1 -- 3 to 18 cm; very dark grayish brown (10YR 3/2) ashy sandy loam, light brownish gray (10YR 6/2), dry; weak fine and medium platy structure; very friable, loose, nonsticky, nonplastic; 10 percent subrounded gravels; strongly acid (pH 5.2); clear smooth boundary.

A2 -- 18 to 42 cm; dark brown (10YR 3/3) cobbly ashy sandy loam, light brownish gray (10YR 6/2), dry; weak fine and medium subangular blocky structure; very friable, loose, nonsticky, nonplastic; 10 percent subrounded cobbles and 10 percent subrounded gravels; moderately acid (pH 5.6); clear wavy boundary. (Combined thickness of A horizons is 36 to 50 cm)

AB -- 42 to 66 cm; dark brown (10YR 3/3) gravelly ashy sandy clay loam, pale brown (10YR 6/3), dry; moderate fine and medium subangular blocky structure; firm, slightly hard, slightly sticky, slightly plastic; 5 percent subangular cobbles and 20 percent subrounded gravles; strongly acid (pH 5.3); abrupt wavy boundary. (0 to 30 cm thick)

2Btk -- 66 to 92 cm; dark brown (10YR 3/3) extremely cobbly clay; moderate fine angular blocky structure; firm, hard, slightly sticky, moderately plastic; 20 percent prominent clay films on all faces of peds; 8 percent fine irregular carbonate masses on bottom of rock fragments; 5 percent subrounded stones and 45 percent rounded cobbles and 20 percent rounded gravels; neutral (pH 6.8); abrupt wavy boundary. (12 to 50 cm thick)

2Btkqm -- 92 to 110 cm; dark yellowish brown (10YR 4/6) very strongly cemented duripan; extremely cobbly clay; strong fine angular blocky structure; 15 percent distinct clay films on all faces of peds; 5 percent fine irregular carbonate masses on bottom of rock fragments and 45 percent coarse silica masses in matrix; 50 percent subrounded cobbles and 25 percent rounded gravels; neutral (pH 7.1); clear wavy boundary.

2Btqm -- 110 to 164 cm; dark yellowish brown (10YR 4/4) strongly cemented duripan; extremely cobbly sandy clay; strong fine angular blocky structure; 12 percent distinct clay films on all faces of peds; 40 percent coarse silica masses in matrix and 30 percent coarse distinct silica concretions on bottom of rock fragments; 5 percent subrounded stones and 60 percent rounded cobbles and 15 percent rounded gravels; moderately alkaline (pH 8.0).

TYPE LOCATION: Crook County, Oregon; located about 21 km south of the town of Mitchell; 130 m south and 585 m west of the NE corner of section 10, T. 14 S., R. 21 E.; Mount Pisgah 7.5' USGS Quad.; latitude 44.3784280, longitude -120.1915000, WGS84 Datum (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 5 to 8 degrees C
Soil Moisture: Usually moist but are dry for 60 to 90 days following the summer solstice. Xeric soil moisture regime.
Depth to duripan: 50 to 100 cm
Reaction: strongly acid to moderately alkaline

Estimated properties of layers with andic soil properties
*Andic Soil Properties: Upper boundary at mineral soil surface, 36 to 76 centimeters thick
*0.2 to 2.0 mm fraction: 60 to 80 percent of fine earth
*P Retention: 25 to 50 percent
*Acid oxalate Al + 1/2Fe - 0.4 to 0.8 percent
*Volcanic glass content in 0.2 to 2.0 mm fraction - 5 to 60 percent
*Water content at 1500kPa (air dry): 8 to 12 percent

Particle Size Control Section
*Upper part (ashy)--36 to 50 cm thick
*Clay content--7 to 30 percent
*Rock fragment content--0 to 25 percent
*Lower Part (clayey-skeletal)--12 to 50 cm thick
*Clay content--35 to 60 percent
*Rock fragment content--45 to 90 percent

A and AB horizons
*Hue--10YR dry or wet
*Value--2 or 3 moist, 6 dry
*Chroma--1 to 3 moist, 2 or 3 dry
*Fine earth texture--ashy sandy loam, ashy loam or ashy sandy clay loam
*Clay content--7 to 30 percent
*Sand content--35 to 70 percent
*Organic matter content--1 to 4 percent
*Total Fragments: 0 to 25 percent (gravel)

2Btk horizon
*Hue--10YR dry or wet
*Value--2 or 3 moist, 3 or 4 dry
*Chroma--2 to 3 moist, 2 or 3 dry
*Fine earth texture--clay, or clay loam
*Clay content--35 to 55 percent
*Sand content--20 to 40 percent
*Organic matter content--0.5 to 2 percent
*Total Fragments--35 to 75 percent
*Gravel content--10 to 35 percent
*Cobble content--15 to 60 percent
*Stone content--0 to 5 percent

2Btkqm horizon(s)
*Hue--10YR dry or wet
*Value--3 or 4 moist, 4 or 5 dry
*Chroma--4 to 6 moist, 4 to 7 dry
*Fine earth texture--clay, sandy clay, or clay loam
*Clay content--35 to 60 percent percent
*Sand content--25 to 60 percent
*Organic matter content--0.5 to 1 percent
*Cementation--strongly to indurated
*Total Fragments--45 to 90 percent
*Gravel content--15 to 35 percent
*Cobble content--20 to 80 percent
*Stone content--0 to 5 percent

COMPETING SERIES:
Threebuck--greater than 100 cm to lithic contact; lacks duripan

GEOGRAPHIC SETTING:
Elevation--1200 to 1675 m
Climate--cold, moist winters and warm, dry summers
Mean annual precipitation--300 to 450 mm
Mean annual air temperature--5 to 8 degrees C
Frost-free period--50 to 90 days
Lithology--volcanic ash from Mt. Mazama over fanglomerate materials of the assumed Rattlesnake Formation.

GEOGRAPHICALLY ASSOCIATED SOILS:
Wahstal--occur on adjacent pediments, footslopes and toeslopes; less than 50 cm to duripan
Normauk--occur on adjacent north slopes; greater than 100cm to restrictive feature
Canest--occur on scablands, lava benches; less than 25 cm to lithic contact

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--well drained
Saturation during normal years--none
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--Moderately high in upper part, moderately low in lower part

USE AND VEGETATION: Use--timber production, livestock grazing, wildlife habitat
Potential native vegetation--ponderosa pine, Idaho fescue, elk sedge, mountain big sagebrush
Typical Plant Association--PIPO/ARTRV/FEID-PSSPS (CPS131)

DISTRIBUTION AND EXTENT: Central Oregon, MLRA B-10. These soils are not extensive.

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

SERIES PROPOSED: Crook County Area, Oregon 2015

REMARKS: Diagnostic horizons and features recognized in this pedon are
Ochric epipedon - 3 to 66 cm
Particle-size control section -3 to 92 cm
Duripan - 92 to 110 cm
Soil moisture regime: Xeric.
The Hudspine soil was created to describe forested, clayey, outwash pediments that occur near Big Summit Prairie in the Ochoco National Forest. These outwash remnants probably formed during the Pliocene/Pleistocene. They are composed of deep deposits of rounded alluvial gravel and cobble, mostly basalt in origin. They are resistant landforms that have since weathered heavy argillics and duripans.

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National Cooperative Soil Survey
U.S.A.