LOCATION SLAUGHTERHOUSE          OR

Tentative Series
IRD. JLW/RJO/DAL
03/2013

SLAUGHTERHOUSE SERIES

The Slaughterhouse series consists of deep, well drained soils formed in a mantle of volcanic ash over metavolcanic colluvium on mountain backslopes and summits. Slope gradients are 0 to 60 percent. Mean annual precipitation is about 33 inches and mean annual temperature about 45 degrees F.

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

TYPICAL PEDON: Slaughterhouse ashy silt loam - conifer forest, on a 45 percent south-facing slope at an elevation of 5,520 feet. (Colors are for moist soil unless otherwise noted. Soil textures are apparent field textures.)

Oi--0 to 1 inch; slightly decomposed needles, twigs, grasses, logs

Oe--1 to 2 inches; moderately decomposed needles, grasses

A--2 to 4 inches; dark reddish brown (5YR 3/2) ashy silt loam, reddish brown (5YR 5/3) dry; weak very fine and fine granular structure; soft, very friable, nonsticky, nonplastic and weakly smeary; few very fine and fine roots; common very fine irregular and few very fine tubular pores; 5 percent gravel; neutral (pH 6.8); clear wavy boundary. (2 to 14 inches thick)

Bw--4 to 17 inches; brown (7.5YR 4/4) ashy silt loam, light brown (7.5YR 6/4) dry; weak medium and fine subangular blocky structure; soft, very friable, nonsticky, nonplastic and weakly smeary; few very fine, fine and medium roots; common very fine irregular and tubular pores; 5 percent gravel; neutral (pH 6.8); abrupt wavy boundary. (6 to 16 inches thick)

2Eb--17 to 25 inches; brown (7.5YR 4/4) very gravelly loam, light brown (7.5YR 6/4) dry; weak medium and fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine, fine and medium roots; few very fine tubular and many very fine irregular pores; 35 percent gravel; neutral (pH 6.8); clear wavy boundary. (4 to 20 inches thick)

2Btb--25 to 44 inches; brown (7.5YR 4/4) very gravelly loam, light brown (7.5YR 6/4) dry; weak medium subangular blocky structure parting to weak fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; few faint clay films on ped faces; few fine and medium roots; common very fine irregular pores; 40 percent gravel, and 10 percent cobbles; neutral (pH 6.8); abrupt wavy boundary. (12 to 23 inches thick)

2R--44 inches; metavolcanic bedrock

TYPE LOCATION: Grant County, Oregon
Section 26 (NE , NW , SE ), T. 11 S., R. 33 E.
Latitude: 44 degrees, 34 minutes, 59 seconds, north
Longitude: 118 degrees, 42 minutes, 05 seconds, west
UTM Zone 11; 4,937,830 northing; 364,940 easting NAD 27
USGS Quadrangle: Dixie Meadows

RANGE IN CHARACTERISTICS:
Soil Temperature: frigid regime
Mean Annual Soil Temperature: 40 to 44 degrees F
Mean Summer Soil Temperature: 48 to 53 degrees F
Mean Winter Soil Temperature: 32 to 37 degrees F
Soil Moisture: xeric regime, dry 45 to 60 consecutive days in summer

Particle-size Control Section: mineral surface to 40 inches below the mineral surface
Upper part (ashy): 14 to 20 inches thick
Clay content, average: 4 to 8 percent
Rock fragment content, average: 0 to 10 percent
Lower part (loamy-skeletal): 20 to 26 inches thick
Clay content, average: 18 to 27 percent
Rock fragment content, average: 40 to 55 percent

Diagnostic Horizons and Features:
andic soil properties: upper boundary at the mineral surface; 14 to 20 inches thick
Al+1/2Fe(aox): 1.0 to 2.0 percent
bulk density: 0.65 to 1.0 g/cc
P retention: 40 to 70 percent
0.02-2.0 mm fraction: 40 to 60 percent of fine earth
glass content in the 0.02-2.0mm fraction: 60 to 90 percent
water content at 1500 kPa (air dried): 5 to 12 percent
8Si + 2Fe (aox): 5 to 8 percent with 8Si being more than twice the 2Fe (amorphic)
ochric epipedon:
cambic horizon: 10 to 23 inches thick
argillic horizon: 12 to 23 inches thick
lithic contact, depth: 40 to 60 inches

A horizon:
color, moist: 5YR 3/2; 7.5YR 3/4; 10YR 3/3, 4/3, 4/4
color, dry: 5YR 5/3; 7.5YR 5/4, 6/3; 10YR 5/3, 6/2, 6/4
texture: ASHY-SIL
clay content: 4 to 8 percent
rock fragment content: 0 to 15 percent
gravel: 0 to 10 percent
cobbles: 0 to 5 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3.
organic carbon: 1 to 5 percent

Bw horizon:
color, moist: 7.5YR 4/3, 4/4; 10YR 5/4
color, dry: 7.5YR 6/4; 10YR 7/4
texture: ASHY-SIL
clay content: 4 to 8 percent
rock fragment content: 0 to 10 percent
gravel: 0 to 10 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3.
organic carbon: 0.6 to 1.0 percent

2Eb horizon: (also horizonated as 2Bwb, 2Ab)
color, moist: 7.5YR 4/4; 10YR 4/3, 5/3, 5/4
color, dry: 7.5YR 6/4; 10YR 6/3, 6/4, 7/3
texture: GRV-SL, STV-SL, GRV-L
clay content: 10 to 18 percent
rock fragment content: 35 to 50 percent
gravel: 20 to 40 percent
cobbles: 0 to 20 percent
stones: 0 to 10 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3

2Btb horizon:
color, moist: 7.5YR 4/4, 5/3; 10YR 4/3, 4/4, 5/3
color, dry: 7.5YR 6/4; 10YR 5/3, 6/3, 6/4
texture: GRV-L, GRV-SCL, CBV-SCL, STV-SCL, GRX-SL, STX-SL
clay content: 18 to 30 percent
rock fragment content: 35 to 65 percent
gravel: 20 to 50 percent
cobble: 2 to 25 percent
stones: 0 to 20 percent
reaction: slightly acid to neutral; pH: 6.1 to 7.3
organic carbon: 0.0 to 1.2 percent

COMPETING SERIES:
McWillar (T): lower part of the particle-size control section averages 12 to 18 percent clay and is over metasedimentary bedrock
McWillis (T): very deep (>60 inches) to a lithic bedrock; lower part of the particle-size control section averages 12 to 18 percent clay
Pahto (T): moderately deep (20 to 40 inches) to paralithic bedrock
Shilla: lower part of the particle-size control section averages 28 to 34 percent clay, (need to determine if the ashy material is glassy or amorphic)

GEOGRAPHIC SETTING:
Landform: on mountain backslopes and summits
Slope gradient: 0 to 60 percent
Parent material: volcaniclastic volcanic ash overlying colluvium
Lithology: Mazama ash overlying metavolcanic rocks
Elevation: 4,200 to 5,600 feet
Climate: cold, wet winters and cool, dry summers
Mean annual precipitation: 25 to 41 inches
Mean annual air temperature: 38 to 42 degrees F
Frost-free period: 35 to 80 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Analulu: on convex backslopes and ridges, moderately deep to bedrock with a minor influence of volcanic ash under Douglas fir, ponderosa pine or grand fir forest;
Gutridge: on north-aspect backslopes and footslopes; moderately deep to bedrock with a thick ash mantle under moist (udic) grand fir forest
Kingbolt: on ridges, benches and shoulder slopes, moderately deep to bedrock with a thick volcanic ash mantle under grand fir and Douglas fir forest

DRAINAGE AND PERMEABILITY:
Drainage: well drained
Permeability: moderate in ash mantle and moderately slow in argillic horizon

USE AND VEGETATION:
Use: Woodland, watershed, wildlife, recreation, range
Native vegetation: grand fir, Douglas fir, lodgepole pine, big huckleberry, grouse huckleberry, Oregon boxwood, birchleaf spirea, heartleaf arnica, white hawkweed, pinegrass, elk sedge, mountain brome and western fescue.
Plant association: Dominant: ABGR/VASC (grand fir/grouse huckleberry); may include: PICO(ABGR)/VASC/CARU (lodgepole pine-grand fir/grouse huckleberry/pinegrass), ABGR/VAME (grand fir/big huckleberry), ABGR/SPBE2 (grand fir/birchleaf spirea)

DISTRIBUTION AND EXTENT:
Distribution: Blue Mountains of northeastern Oregon; MLRA 10
Extent: small

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES PROPOSED: Malheur National Forest, Oregon 2007. Name is from a valley.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon: 2 to 4 inches; A
cambic horizon: 4 to 17 inches; Bw
argillic layer: 25 to 44 inches; 2Btb
andic soil properties: 2 to 17 inches; A, Bw
particle-size control section:
ashy part: 2 to 17 inches; A, Bw
loamy-skeletal part: 17 to 42 inches; 2Eb, 2Btb
lithic contact: 44 inches; 2R

Amorphic mineralogy class for the ash mantle based on laboratory data for soils with undisturbed ashy silt loam mantle and xeric moisture regime with 45 to 60 consecutive dry days in summer, in eight out of 13 pedons sampled.

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National Cooperative Soil Survey
U.S.A.