LOCATION VALPEY OR
Tentative Series
IRD. JRD/DAL/TDT
03/2013
VALPEY SERIES
The Valpey series consists of very deep well drained soils formed in volcanic ash over mixed colluvium from basalt, rhyolite and tudd on mountain sideslopes. Slopes range from 5 to 30 percent. Mean annual precipitation is about 20 inches and mean annual temperature is about 43 degrees F.
TAXONOMIC CLASS: Ashy over loamy, glassy over isotic, frigid Alfic Humic Vitrixerands
TYPICAL PEDON: Valpey ashy sandy loam - upland forest, on a 10 percent convex slope, north aspect, at an elevation of 5760 feet. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 2 inches, slightly decomposed pine litter
A1--2 to 5 inches, brown (10YR 4/3) ashy sandy loam, very dark brown (10YR 2/2) moist; moderate thin and medium platy structure; very soft, very friable, non-sticky and non-plastic; many very fine and fine roots; many very fine and fine vesicular pores; 5 percent gravel, moderately acid (pH 5.8); abrupt smooth boundary.
A2--5 to 19 inches; brown (10YR 4/3) ashy sandy loam, very dark brown (10YR 2/2) moist; moderate fine and medium subangular blocky structure; soft, friable, slightly sticky and non-plastic; many very fine, fine and medium, and common coarse roots; many very fine and fine tubular pores; 10 percent gravel, moderately acid (pH 6.0); clear smooth boundary. (Combined thickness of the A horizons is 14 to 20 inches.)
2Bt1--19 to 40 inches; dark yellowish brown (10YR 4/6) sandy clay loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky stucture; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, medium and coarse roots; many very fine and fine tubular pores; common faint clay films bridgingsand grains; 10 percent gravel, 4 percent cobbles; slightly acid (pH 6.4); clear smooth boundary. (20 to 30 inches thick)
2Bt2--40 to 62 inches; dark yellowish brown (10YR 4/6) sandy clay loam; dark yellowish brown (10YR 3/4) moist; moderate fine and medium subangular blocky structure, hard, firm, slightly sticky, and slightly plastic; common fine and medium roots; many very fine and fine tubular pores; common faint clay films bridging sand grains; 10 percent gravel; slightly acid (pH 6.2)
TYPE LOCATION: Crook County, Oregon, located northwest of small knoll off the USFS 1750-691 road in the eastern Maury Mountains;
NE1/4 of NE1/4, Sec. 4, T.18 S, R. 20 E.
Latitude: 44 degrees, 02 minutes and 42 seconds North
Longitude: 120 degrees, 19 minutes and 07 seconds West
UTM Coordinates: Zone: 10 Northing: 4880397 Easting: 714817
RANGE IN CHARACTERISTICS:
Soil temperature: frigid regime
mean annual soil temperature: 37 to 41 degrees F.
mean summer soil temperature: 44 to 49 degrees F.
mean winter soil temperature: 32 to 36 degrees F.
Soil moisture: xeric regime; dry 60 to 90 consecutive days in summer and early fall
Particle-size control section: mineral surface to 40 inches below the mineral surface
upper part (ashy): thickness: 14 to 20 inches
clay content (weighted average): 7 to 18 percent
rock fragment content (weighted average): 5 to 15 percent
lower part (loamy): thickness: 20 to 26 inches
clay content (weighted average): 20 to 35 percent
rock fragment content (weighted average): 5 to 15 percent
Diagnostic horizons and features:
andic soil properties: upper boundary at the mineral soil surface 14 to 20 inches thick
Al+1/2Fe (ammonium oxalate): 0.4 to 0.8 percent
P retention: 25 to 50 percent
0.2 to 2.0 mm fraction: 60 to 80 percent of fine earth
glass content in the 0.2 to 2.0 mm fraction: 30 to 50 percent
water content at 1500 kPa tension (air dried): 7 to 12 percent
mollic epipedon: 20 to 40 inches thick
argillic horizon: 30 to 50 inches thick
lithic contact, depth: 60 to 80 inches
Major horizons:
A horizon
color, moist: 10YR 2/2, 2/3
color, dry: 10YR 4/3
texture: ashy loamy sand, ashy sandy loam
clay content: 7 to 18 percent
rock fragment content: 5 to 15 percent
gravel: 5 to 15 percent
cobbles: 0 to 5 percent
stones: 0 to 5 percent
boulders: 0 to 5 percent
reaction: slightly to moderately acid; pH: 5.6 to 6.5
2Bt horizon
color, moist: 10YR 3/3, 3/4
color, dry: 10YR 4/4, 4/5, 4/6
texture: sandy clay loam, clay loam
clay content: 20 to 35 percent
rock fragment content: 5 to 15 percent
gravel: 0 to 10 percent
cobbles: 0 to 5 percent
stones: 0 to 2 percent
boulders: 0 to 2 percent
reaction: slightly acid to neutral, pH: 6.1 to 7.3
COMPETING SERIES:
There are no competing series.
GEOGRAPHIC SETTING:
Landform: hillslopes, valley sideslopes and mountain backslopes
Slope gradient: 5 to 40 percent
Parent material: volcanic ash over colluvium
Lithology: basalt, rhyolite, pyroclastic tuff
Elevation: 4000 to 6000 feet
Climate: cold, wet winters and hot, dry summers
Mean annual precipitation: 18 to 22 inches
Mean annual temperature: 40 to 45 degrees F.
Frost-free period: 50 to 80 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Pilotbutte soils occur on plateau tops, ash pockets and upland swalesand lack the contrasting particle-size control section.
DRAINAGE AND PERMEABILITY:
Drainage: well drained
Permeability: moderately rapid in the ash mantle and moderately slow in the subsoil
USE AND VEGETATION:
Use: timber production, grazing, wildlife habitat and water supply
Natural vegetation: ponderosa pine, pinegrass, bluegrass, snowberry, lupine and strawberry
DISTRIBUTION AND EXTENT:
Distribution: central Oregon
Common ecological region: 13, Blue Mountains
Major land resource area: 10
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Crook County, Oregon, 2004
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
andic soil material (ash) 2 to 19 inches
mollic epipedon 2 to 40 inches
argillic horizon 19 to 62 inches
Plant association: CPG221, Ponderosa pine; pinegrass (Johnson and Clausnitzer, 1992, Plant Associations of the Blue and Ochoco Mountains);
National Cooperative Soil Survey
U.S.A.