LOCATION VO ID
Established Series
Rev. BJD/RGK/CBR
05/2018
VO SERIES
Landscape--hills
Landform--hillslopes
Slope--5 to 25 percent
Parent material--loess-influenced colluvium derived from basalt
Mean annual precipitation--about 375 mm
Mean annual air temperature--about 3.3 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--cryic
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Xeric Calcicryolls
TYPICAL PEDON: Vo stony loam in an area of rangeland (Colors are for dry soil unless otherwise noted.)
Ak--0 to 13 cm; grayish brown (10YR 5/2) stony loam, dark brown (10YR 3/3) moist; weak fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine and common medium roots; few fine and medium tubular pores; 10 percent gravel, 5 percent cobbles, and 10 percent stones; finely disseminated calcium carbonate; slightly effervescent; moderately alkaline (pH 7.9); clear wavy boundary
Bk1--13 to 30 cm; brown (10YR 5/3) cobbly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine and common medium roots; common fine and medium tubular pores; finely disseminated calcium carbonate; 10 percent gravel, 15 percent cobbles, and 2 percent stones; strongly effervescent; moderately alkaline (pH 8.0); clear wavy boundary
Bk2--30 to 53 cm; pale brown (10YR 6/3) very cobbly loam, brown (10YR 5/3) moist; weak coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine and few medium roots; few fine and medium tubular pores; 25 percent gravel, 20 percent cobbles, and 5 percent stones; calcium carbonate coatings 1 to 2 mm thick on bottom of rock fragments and finely disseminated calcium carbonate (25 percent calcium carbonate equivalent); violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary
Bk3--53 to 81 cm; very pale brown (10YR 8/3) very cobbly loam, pale brown (10YR 6/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine, fine, and medium roots; few fine and medium tubular pores; 30 percent gravel, 20 percent cobbles, and 5 percent stones; calcium carbonate coatings 1 to 2 mm thick on bottom of rock fragments and finely disseminated calcium carbonate (25 percent calcium carbonate equivalent); violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary
Bkq--81 to 150 cm; very pale brown (10YR 8/3) extremely gravelly loam, pale brown (10YR 6/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine, fine, and medium roots; few fine tubular pores; 45 percent gravel, 25 percent cobbles, and 2 percent stones; calcium carbonate and silica coatings 1 to 2 mm thick on bottom of rock fragments and finely disseminated calcium carbonate (25 percent calcium carbonate equivalent); violently effervescent; moderately alkaline (pH 8.4)
TYPE LOCATION: Clark County, Idaho; latitude 44.19028 degrees north, longitude 113.00167 degrees west, datum WGS 84
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--3.3 to 5.6 degrees C
Thickness of mollic epipedon--25 to 36 cm
Depth to calcic horizon--25 to 40 cm
Particle-size control section (weighted averages)
Clay content--12 to 18 percent
Total rock fragment content--45 to 60 percent
Ak horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Clay content--15 to 18 percent
Total rock fragment content--15 to 35 percent
Gravel content--10 to 15 percent
Cobble content--0 to 15 percent
Stone content--5 to 10 percent
Calcium carbonate equivalent--2 to 10 percent
Reaction--pH 7.6 to 8.0
Thickness--10 to 18 cm
Bk1 horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Clay content--15 to 20 percent
Total rock fragment content--15 to 35 percent
Gravel content--10 to 15 percent
Cobble content--5 to 15 percent
Stone content--0 to 15 percent
Calcium carbonate equivalent--5 to 14 percent
Reaction--pH 7.6 to 8.0
Thickness--15 to 23 cm
Bk2 and Bk3 horizons
Value--6 to 8 dry, 5 or 6 moist
Chroma--2 or 3 dry or moist
Clay content--12 to 18 percent
Total rock fragment content--35 to 60 percent
Gravel content--15 to 30 percent
Cobble content--15 to 30 percent
Stone content--5 to 15 percent
Calcium carbonate equivalent--20 to 30 percent
Reaction--pH 8.0 to 8.4
Thickness--25 to 50 cm
Bkq horizon
Value--6 to 8 dry, 5 or 6 moist
Chroma--2 or 3 dry or moist
Texture (less than 2-mm fraction)--loam, sandy loam
Clay content--12 to 18 percent
Total rock fragment content--35 to 85 percent
Gravel content--20 to 45 percent
Cobble content--15 to 25 percent
Stone content--0 to 15 percent
Calcium carbonate equivalent--20 to 30 percent
Reaction--pH 8.0 to 8.4
COMPETING SERIES:
Swan Flat--no accumulations of secondary silica; parent material derived from sedimentary rock
GEOGRAPHIC SETTING:
Elevation--1620 to 2250 m
Mean annual precipitation--300 to 400 mm
Mean annual air temperature--2.2 to 4.4 degrees C
Frost-free period--30 to 60 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--5 to 25 um/sec
USE AND VEGETATION:
Major uses--rangeland, wildlife habitat
Potential natural vegetation--low sagebrush, bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, prairie Junegrass, Nevada bluegrass, Hood's phlox
DISTRIBUTION AND EXTENT: Small extent in east-central Idaho; MLRA 12
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clark County, Idaho; 2018
REMARKS:
Diagnostic horizons and other features recognized in this pedon
Mollic epipedon--zone from the surface to a depth of 30 cm (Ak and Bk1 horizons)
Calcic horizon--zone from 30 to 150 cm (Bk2, Bk3, and Bkq horizons)
Particle-size control section--25 to 100 cm
Taxonomic version--Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.