LOCATION BOLOBIN                 OR

Established Series
Rev. RJO/DAL/KMS
11/2018

BOLOBIN SERIES

Landscape--plateaus, mountains
Landform--plateaus, mountain slopes
Slope--0 to 60 percent
Parent material--thin mantle of mixed volcanic ash and loess over colluvium derived from basalt
Mean annual precipitation--about 460 mm
Mean annual air temperature--about 6 degrees C
Depth class--moderately deep to lithic bedrock
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic

TAXONOMIC CLASS: Fine-loamy, isotic, frigid Vitrandic Argixerolls

TYPICAL PEDON: Bolobin ashy silt loam, forested, on a 20-percent, south facing slope at an elevation of 1256 m

Oi--0 to 3 cm; slightly decomposed needles, grasses, and woody debris

Oe--3 to 5 cm; moderately decomposed organic matter

A--5 to 25 cm; ashy silt loam, brown (10YR 5/3) dry, black (7.5YR 2.5/1) moist; weak fine granular structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine and few medium roots; common very fine irregular and tubular pores; 5 percent gravel; slightly acid (pH 6.3); clear smooth boundary

ABt--25 to 36 cm; ashy silt loam, brown (7.5YR 4/2) dry, black (7.5YR 2.5/1) moist; moderate medium subangular blocky structure parting to weak fine granular; slightly hard, friable, slightly sticky and nonplastic; few faint clay films on ped faces; common very fine and few fine and medium roots; common very fine irregular and tubular pores and few fine tubular pores; 5 percent gravel; slightly acid (pH 6.5); clear smooth boundary

2Bt--36 to 79 cm; cobbly silt loam, brown (7.5YR 4/3) dry, dark brown (7.5YR 3/2) moist; moderate medium subangular blocky structure parting to weak fine subangular blocky; hard, firm, moderately sticky and slightly plastic; common faint clay films on ped faces; few fine and medium roots; common very fine irregular and tubular pores; 5 percent gravel and 20 percent cobbles; slightly acid (pH 6.5); abrupt wavy boundary

2R--79 cm; basalt

TYPE LOCATION: Grant County, Oregon, about 755 m west and 985 m south of the northeast corner of section 14 , T. 9 S., R. 32 E.; latitude 44.7876265, longitude -118.8284725, datum WGS 84 (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--6 to 8 degrees C
Soil moisture--dry 60 to 90 consecutive days in summer
Thickness of mollic epipedon--50 to 75 cm
Depth to lithic contact--50 to 100 cm
Thickness of ash-influenced layers--18 to 48 cm

Estimated properties of layers influenced by volcanic ash
*Ammonium oxalate extractable Al + 1/2 Fe--0.2 to 0.7 percent
*0.02- to 2.0-mm fraction--30 to 50 percent
*Glass content in 0.02- to 2.0-mm fraction--15 to 30 percent
*Phosphate retention--25 to 45 percent
*8 x Si plus 2 x Fe--1 to 6 percent

Particle-size control section
*Clay content--23 to 30 percent
*Total rock fragment content--10 to 25 percent

A horizon
Hue--5YR, 7.5YR, 10YR
Value--2.5 or 3 moist, 3 to 5 dry
Chroma--1 to 3 moist, 2 or 3 dry
Fine-earth texture--ashy loam, ashy silt loam
Clay content--8 to 18 percent
Sand content--35 to 40 percent
Organic matter content--3 to 12 percent
Total rock fragment content--0 to 5 percent
Gravel content--0 to 5 percent
Reaction--5.6 to 7.3
Thickness--18 to 23 cm

ABt horizon
Hue--5YR, 7.5YR, 10YR
Value--2.5 or 3 moist, 3 to 5 dry
Chroma--1 to 3 moist, 2 or 3 dry
Fine-earth texture--ashy loam, ashy silt loam
Clay content--18 to 25 percent
Sand content--25 to 40 percent
Organic matter content--1 to 3 percent
Total rock fragment content--0 to 10 percent
Gravel content--0 to 10 percent
Reaction--6.1 to 6.5
Thickness--10 to 25 cm

2Bt horizon
Hue--5YR, 7.5YR, 10YR
Value--2.5 to 4 moist, 3 to 5 dry
Chroma--2 to 4 moist, 3 or 6 dry
Fine-earth texture--loam, silt loam
Clay content--25 to 35 percent
Sand content--25 to 40 percent
Organic matter content--1 to 2 percent
Total rock fragment content--0 to 30 percent
Gravel content--0 to 20 percent
Cobble content--0 to 20 percent
Reaction--6.1 to 6.5
Thickness--15 to 53 cm

COMPETING SERIES:
Bly--more than 100 cm to a duripan
Bolony--5 to 15 percent volcanic glass in surface layer
Forbord, Forshey, Lidos, Melhorn, Salcreek--no restriction in upper 150 cm
Hess, Nibolob, Vangoe--lithic contact at a depth of 100 to 150 cm
Raycreek--less than 15 percent rock fragments throughout argillic horizon
Spartabutte--more than 40 percent sand in substratum

GEOGRAPHIC SETTING:
Elevation--930 to 1700 m
Climate--cold, wet winters; cool, dry summers
Mean annual precipitation--370 to 740 mm
Mean annual air temperature--4 to 7 degrees C
Frost-free period--45 to 120 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Fivebit--on plateaus and backslopes; shallow to bedrock; minor influence of volcanic ash in loamy-skeletal colluvium; under scattered ponderosa pine, Douglas-fir, or western juniper and big sagebrush and Idaho fescue
Klickson--on north-facing scarp slopes, structural benches, and lower mountain slopes; deep to bedrock; skeletal particle-size control section; mixed ash mantle; under Douglas-fir, ponderosa pine, ninebark, and oceanspray
Nibolob--on gently sloping areas of plateaus; deep to bedrock; mixed ash mantle; under Douglas-fir or ponderosa pine forest
Anatone--on plateaus, ridgetops, and south- or west-facing slopes; shallow; no argillic horizon; skeletal particle-size control section; minor ash influence; under sagebrush, Idaho fescue, and bluebunch wheatgrass
Melhorn--on backslopes and footslopes; very deep; mixed ash mantle; under Douglas-fir, ponderosa pine, or grand fir forest

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Saturation during normal years--none
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)-moderately high

USE AND VEGETATION:
Use--timber production, watershed, wildlife habitat, recreation, livestock grazing
Potential native vegetation--ponderosa pine, Douglas-fir, grand fir, western juniper, lodgepole pine, western larch, pinegrass, elk sedge, heartleaf arnica, tailcup lupine, Idaho fescue, common snowberry, northwestern sedge, bluebunch wheatgrass, common yarrow, Virginia strawberry, white spirea, low Oregon grape, white hawkweed, baldhip rose, onespike oatgrass, western fescue, cheatgrass, Sandberg bluegrass, arrowleaf balsamroot

DISTRIBUTION AND EXTENT: Foothills of central Rocky Mountains and Blue Mountains; MLRA 10; small extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Grant County, Oregon; 2012

REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Mollic epipedon--zone from 5 to 79 cm
*Argillic horizon--zone from 25 to 79 cm
*Volcanic glass--zone from 5 to 36 cm
*Depth to lithologic discontinuity--36 cm
*Particle-size control section--zone from 25 to 79 cm

10/2018--OSD reformatted according to SSR 1 Technical Note 11.

ADDITIONAL DATA: National Soil Survey Laboratory pedon number 99OR023006

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National Cooperative Soil Survey
U.S.A.