LOCATION BOCKER WA+OR
Established Series
Rev. KDV/RJE/KWH
09/2019
BOCKER SERIES
Landscape--plateaus, hills, mountains
Landform-structural benches, hillslopes, mountain slopes
Slope--0 to 90 percent
Parent material--colluvium and residuum derived from basalt mixed with loess and a small amount of volcanic ash in the upper part
Mean annual precipitation--about 640 mm
Mean annual air temperature--about 6 degrees C
Depth class--very shallow
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Lithic Haploxerolls
TYPICAL PEDON: Bocker very cobbly silt loam in an area of rangeland
A--0 to 5 cm; very cobbly silt loam, reddish brown (5YR 5/3) dry, dark reddish brown (5YR 3/2) moist; weak medium and thick platy structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine irregular pores; 20 percent cobbles and 30 percent gravel; slightly acid (pH 6.4); clear smooth boundary
Bw--5 to 25 cm; very gravelly loam, reddish brown (5YR 5/3) dry, dark reddish brown (5YR 3/3) moist; weak fine angular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; common very fine irregular pores and few very fine tubular pores; 40 percent gravel; neutral (pH 6.6); abrupt irregular boundary
R--25 cm; basalt
TYPE LOCATION: Klickitat County, Washington, about 26 km northeast of Goldendale; 425 m east and 275 m north of the southwest corner of section 33, T. 6 N., R. 18 E.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon and depth to bedrock--10 to 25 cm
Mean annual soil temperature--6 to 8 degrees C
Moisture control section--usually moist, but dry 75 to 90 consecutive days
Reaction--6.1 to 7.3
Particle-size control section--loam, silt loam, ashy loam, ashy silt loam; 18 to 27 percent clay
Rock fragment content--35 to 70 percent, consisting of gravel, cobbles, and stones
Estimated volcanic glass content--2 to 15 percent
Acid oxalate Al plus 1/2 Fe--0.3 to 1.0 percent
Color of solum--typically hue of 5YR, 7.5YR, or 10YR; value of 4 or 5 dry, 2 or 3 moist; and chroma of 2 or 3 moist, 2 to 4 dry
A horizon
Thickness--3 to 8 cm
Bw horizon
Thickness--8 to 20 cm
COMPETING SERIES:
Agassiz--dry 45 to 60 consecutive days following summer solstice
Anatone--25 to 50 cm (shallow) to a lithic contact (basalt); dry 60 to 75 consecutive days following summer solstice
Bluecanyon--25 to 50 cm (shallow) to a lithic contact (argillite)
Dipcreek--25 to 48 cm (shallow) to a lithic contact (sandstone); 12 to 17 percent clay in particle-size control section
Falula--25 to 50 cm (shallow) to a lithic contact (conglomerate)
Foxol--36 to 50 cm (shallow) to a lithic contact (quartzite); dry 45 to 60 consecutive days following summer solstice
Gomine--25 to 50 cm (shallow) to a lithic contact (igneous rock)
Grink--36 to 50 cm (shallow) to a lithic contact (calcareous sandstone); 20 to 25 cm to secondary carbonates
Hogsby--25 to 50 cm (shallow) to a lithic contact (quartzite, argillite)
Kenypeak--5 to 15 percent clay in the particle-size control section
Laschance--25 to 50 cm (shallow) to a lithic contact (dolomite); 5 to 15 percent clay in particle-size control section
Little Pole--25 to 50 cm (shallow) to a lithic contact (andesite)
Nayrib--12 to 18 percent clay in particle-size control section
Onaqui--25 to 50 cm (shallow) to a lithic contact (quartzite); dry 45 to 60 consecutive days following summer solstice
Rexmont--dry 45 to 60 consecutive days following summer solstice; mean annual soil temperature of 3 to 5 degrees C
Starglade--dry 90 to 110 consecutive days following summer solstice; 12 to 18 percent clay and 5 to 20 percent volcanic glass in particle-size control section
Swanner--25 to 50 cm (shallow) to a lithic contact (rhyolite, rhyolitic tuff)
Van Wagoner--25 to 50 cm (shallow) to a lithic contact (quartz diorite porphyry)
GEOGRAPHIC SETTING:
Elevation--2,800 to 6,600 feet
Climate--cool, dry summers; cold, wet winters; cover of snow in December through April
Mean annual precipitation--dominantly 430 to 1000 mm, but ranges from 330 to 430 mm in northeastern Oregon
Mean January air temperature--about -6 degrees C
Mean July air temperature--15 degrees C
Mean annual air temperature--5 to 8 degrees C
Frost-free season--50 to 130 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Berson--no lithic contact
Wrightman--fine-loamy particle-size class; 50 to 100 cm (moderately deep) to a lithic contact (basalt)
Westbutte--50 to 100 cm (moderately deep) to a lithic contact (basalt); mollic epipedon more than 50 cm thick; loamy-skeletal particle-size class
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately high
USE AND VEGETATION:
Use--livestock grazing, recreation
Native vegetation--buckwheat, Sandberg bluegrass, Idaho fescue, bluebunch wheatgrass, bottlebrush squirreltail, stiff sagebrush, low sagebrush
DISTRIBUTION AND EXTENT: South-central Washington and eastern Oregon; MLRA 9; moderate extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Morrow County, Oregon; 1977
REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Mollic epipedon--zone from the surface to a depth of 25 cm
*Depth to lithic contact--25 cm
*Particle-size control section--zone from the surface to a depth of 25 cm
Further investigation is needed to determine the degree and uniformity of the ash influence. Extensive areas were mapped before and after the Andisol order was established. This has resulted in recognition of ashy modifiers and vitrandic criteria in some survey areas but not in others. Both are included in the current concept of the Bocker series in areas where the shallow and skeletal soil characteristics are the dominant features that affect use and management. The relationship of aspect and an ash influence should be considered; north-facing slopes may be best correlated to an ash influence and south-facing slopes to no ash influence.
National Cooperative Soil Survey
U.S.A.