LOCATION PIUTESPRING ORTentative Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Andic Haploxerepts
TYPICAL PEDON: Piutespring silt loam - forested, on a 34 percent southfacing slope at an elevation of 6,170 feet. (Colors are for moist soil unless otherwise noted. Textures are apparent field textures.)
Oi--0 to 1 inch; slightly decomposed needles and twigs
A--1 to 4 inches; dark brown (7.5YR 3/3) ashy silt loam, brown (7.5YR 5/4) dry; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and very fine roots; few fine tubular and very fine irregular pores; 5 percent gravel; slightly acid (pH 6.5); abrupt wavy boundary. (2 to 5 inches thick)
Bw--4 to 11 inches; dark brown (7.5YR 3/4) ashy silt loam, brown (7.5YR 5/4) dry; weak medium subangular blocky structure parting to weak fine subangular blocky; soft, very friable, nonsticky and nonplastic; common very fine and medium, and few fine roots; common very fine irregular, and few fine and very fine tubular pores; 5 percent gravel; slightly acid (pH 6.2); clear wavy boundary. (6 to 11 inches thick)
2ABb--11 to 14 inches; dark brown (7.5YR 3/3) gravelly sandy loam, light brown (7.5YR 6/4) dry; weak medium subangular blocky structure parting to weak fine subangular blocky; soft, very friable, nonsticky and nonplastic; common very fine, and few fine and medium roots; few very fine irregular and fine tubular pores; 20 percent gravel and 5 percent cobbles; slightly acid (pH 6.2); clear smooth boundary. (3 to 20 inches thick)
2Bwb--14 to 38 inches; yellowish brown (10YR 5/4) very gravelly sandy loam, light yellowish brown (10YR 6/4) dry; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; common very fine irregular pores; 50 percent gravel and 5 percent cobbles; slightly acid (pH 6.5); abrupt wavy boundary. (6 to 26 inches thick)
2R--38 inches; granitic bedrock
TYPE LOCATION: Grant County, Oregon
Section 15 (NW1/4, SW1/4, NW1/4), T. 10 S., R. 34 E.
Latitude: 44 degrees, 43 minutes, 04 seconds N.
Longitude: 118 degrees, 36 minutes, 48 seconds W.
UTM coordinates: zone 11; northing: 4,952,649; easting: 372,218; NAD27
USGS Quadrangle: Vinegar Hill
RANGE IN CHARACTERISTICS:
Soil Temperature: frigid regime
Mean Annual Soil Temperature: 40 to 44 degrees F
Mean Summer Soil Temperature: 47 to 51 degrees F
Mean Winter Soil Temperature: 32 to 36 degrees F
Soil Moisture: xeric regime; dry 45 to 60 consecutive days in summer
Particle-size Control Section: from 10 inches below mineral soil surface to the lithic contact
clay content, average: 2 to 9 percent
rock fragment content, average: 35 to 75 percent
Diagnostic Horizons and Features:
andic subgroup properties: upper boundary at the mineral surface; 8 to 13 inches thick
Al+1/2Fe (ammonium oxalate): 1.0 to 2.4 percent
bulk density: 0.65 to 1.00 g/cc
P retention: 60 to 90 percent
0.02-2.0 mm fraction: 40 to 60 percent of fine earth
glass content in the 0.02-2.0 mm fraction: 60 to 90 percent
water content at 1500 kPa (air dried): 5 to 12 percent
cambic horizon, upper: 6 to 11 inches thick
cambic horizon, buried: 6 to 26 inches thick
lithic contact, depth below mineral soil surface: 20 to 40 inches
A horizon:
color, moist: 7.5YR 2.5/2, 3/2, 3/3; 10YR 3/2, 3/3
color, dry: 7.5YR 4/3, 5/3, 5/4; 10YR 5/2, 5/3, 5/4
texture: ASHY-SIL, GR-ASHY-SIL, CB-ASHY-SIL
clay content: 3 to 10 percent
rock fragment content: 0 to 30 percent
gravel: 0 to 15 percent
cobbles: 0 to 15 percent
stones: 0 to 5 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
Bw horizon:
color, moist: 7.5YR 3/4, 4/3; 10YR 3/4, 4/3
color, dry: 7.5YR 4/4, 5/4, 6/4; 10YR 5/4, 6/3, 6/4
texture: ASHY-SIL, GR-ASHY-SIL, CB-ASHY-SIL
clay content: 2 to 8 percent
rock fragment content: 5 to 30 percent
gravel: 5 to 20 percent
cobbles: 0 to 10 percent
stones: 0 to 5 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
2ABb horizon; 2EBb horizon in some pedons:
color, moist: 7.5YR 3/2, 3/3, 4/3; 10YR 3/3, 4/3, 4/4
color, dry: 7.5YR 5/4, 6/4; 10YR 4/4, 5/3, 5/4, 6/3, 6/4
texture: CBV-L, STV-L, STV-SL, GRV-SL, GR-SL
clay content: 2 to 12 percent
rock fragment content: 25 to 55 percent
gravel: 15 to 50 percent
cobbles: 5 to 25 percent
stones: 0 to 20 percent
boulders: 0 to 5 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
2Bwb horizon; some pedons have a 2BCb horizon:
color, moist: 7.5YR 5/3; 10YR 4/2, 4/3, 5/4
color, dry: 7.5YR 5/4; 10YR 5/4, 6/3, 6/4, 7/4
texture: STV-LS, GRX-LS, GRV-LS, STX-LS, GRV-SL, CBV-SL
clay content: 1 to 6 percent
rock fragment content: 35 to 80 percent
gravel: 25 to 50 percent
cobbles: 5 to 25 percent
stones: 0 to 25 percent
boulders: 0 to 5 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
COMPETING SERIES:
Avonville - very deep; formed in glacial outwash; umbric epipedon
Bigcow deep and very deep; formed in basalt colluvium with thin mantle of volcanic ash; clay content in particle-size control section averages 9 to 16 percent
Hondu - very deep
Inkler - very deep; dry for 60 to 75 consecutive days in summer
Juandefuca - very deep; ash mantle has greater than 12 percent (air dried) water content at 1500 kPa (i.e. medial) and volcanic glass content less than 30 percent
McCree - deep to a lithic contact (rhyolite); ash mantle has 5 to 20 percent volcanic glass content; dry 60 to 75 consecutive days in summer
Newhorn - moderately deep to a densic contact (till); dry 60 to 75 consecutive days in summer
Oxerine - moderately deep to a lithic contact (gneiss); dry 60 to 75 consecutive days in summer
Redriver - moderately deep to a lithic contact (basalt); dry 75 to 90 consecutive days in summer
Tunnelcreek - moderately deep to a paralithic contact over metavolcanic bedrock; ash mantle has greater than 12 percent (air dried) water content at 1500 kPa (i.e. medial); clay content in particle-size control section averages 8 to 18 percent
Veridge - moderately deep to a lithic contact (sandstone); thin volcanic ash mantle has 30 to 60 percent volcanic glass content; dry 60 to 75 consecutive days in summer
Wilma moderately deep to lithic contact (granite); 2C or 2BC horizons with hue of 10YR or 2.5Y; dry 60 to 75 consecutive days in summer
Wonder - moderately deep to a lithic contact (andesitic basalt); clay content in particle-size control section averages 9 to 15 percent; rock fragments are subangular or angular
GEOGRAPHIC SETTING:
Landform: surface eroding backslopes of granitic intrusive upthrust blocks
Slope gradient: 0 to 90 percent
Parent material: volcanic ash overlying colluvium and residuum
Lithology: granite
Elevation: 4,900 to 6,170 feet
Climate: cold, wet winters; warm, dry summers
Mean annual precipitation: 26 to 38 inches
Mean annual air temperature: 36 to 41 degrees F.
Frost-free period: 25 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Coyotebluff: on steep backslopes; deep, mollic epipedon, loamy-skeletal, and mixed ash mantle under grand fir, Douglas-fir, Rocky Mountain maple, mallow ninebark, pinegrass and elk sedge
Endcreek: on gently sloping benches and toeslopes; moderately deep, thick ash mantle over loamy-skeletal colluvium; under grand fir, Douglas-fir, grouse wortleberry and pinegrass
Golfer: on steep, convex backslopes; moderately deep, mollic epipedon, loamy-skeletal and minor amount of volcanic ash; under Douglas-fir, ponderosa pine, pinegrass, mallow ninebark and elk sedge
Powderriver: on convex upper backslopes and shoulders; shallow, skeletal soil under open canopy of Douglas-fir or grand fir with pinegrass, and elk sedge
Raggedrock: on planer lower to middle backslopes; deep to paralithic, soft granitic rock; thick ash mantle over very gravelly buried soil; under grand fir, Douglas-fir, big huckleberry, grouse huckleberry and mountain brome
DRAINAGE AND PERMEABILITY:
Drainage: well drained
Permeability: moderate over rapid
USE AND VEGETATION:
Use: timber production, livestock grazing, recreation, wildlife habitat, watershed
Potential native vegetation: grand fir, Douglas-fir, ponderosa pine, birchleaf spiraea, Oregon grape, white hawkweed, showy aster, pinegrass, elk sedge
Plant Association: ABGR/CARU (grand fir/pinegrass) may include PSME/SPBE (Douglas-fir/birchleaf spiraea), PSME/CARU (Douglas-fir/pinegrass) or ABGR/CAGE (grand fir/elk sedge)
DISTRIBUTION AND EXTENT:
Distribution: MLRA 43c; Blue Mountains in eastern Oregon
Extent: Moderate
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Malheur National Forest, Oregon; 2008. Name is from a spring on Boulder Butte quad.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon: 1 to 4 inches; A horizon
cambic horizon, upper: 4 to 11 inches; Bw horizon
cambic horizon, buried: 14 to 38 inches; 2Bwb horizon
andic subgroup properties (ash mantle):1 to 11 inches; A, Bw horizons
particle-size control section: 11 to 38 inches; 2ABb, 2Bwb horizons