LOCATION SAPKIN                  WA

Established Series
Rev. JPE/KWH/KDPL/KH
09/2019

SAPKIN SERIES

Landscape--mountains
Landform--mountain slopes, ridgetops
Slope--0 to 75 percent
Parent material--residuum and colluvium derived from Yakima basalt, minor amount of loess and volcanic ash
Mean annual precipitation--about 640 mm
Mean annual air temperature--about 7 degrees C
Depth class--moderately deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Ultic Argixerolls

TYPICAL PEDON: Sapkin very cobbly loam in an area of rangeland (All textures are apparent field textures.)

A1--0 to 13 cm; very cobbly loam, brown (10YR 5/3) dry, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many very fine irregular pores; 15 percent gravel, 30 percent cobbles, and 10 percent stones; slightly acid (pH 6.4); clear smooth boundary

A2--13 to 41 cm; very cobbly loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; weak very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many very fine irregular pores; 15 percent gravel, 35 percent cobbles, and 5 percent stones; slightly acid (pH 6.4); gradual smooth boundary

AB--41 to 64 cm; very cobbly loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; weak medium subangular blocky structure and weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; common very fine tubular pores; 15 percent gravel, 35 percent cobbles, and 5 percent stones; neutral (pH 6.6); gradual smooth boundary

Bt--64 to 91 cm; very cobbly loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; weak coarse subangular blocky structure; slightly hard, firm, slightly sticky and moderately plastic; common fine and very fine roots; common very fine tubular pores; few distinct clay films in pores; 15 percent gravel, 35 percent cobbles, and 5 percent stones; slightly acid (pH 6.4); abrupt irregular boundary

R--91 cm; fractured basalt

TYPE LOCATION: Kittitas County, Washington, about 37 km northeast of Ellensburg; about 825 m east and 30 m south of the northwest corner of section 32, T. 20 N., R. 21 E.; latitude 47.1895353, longitude -120.2279310, datum WGS 84 (coordinates estimated from section, township, and range)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--7 to 8 degrees C
Soil moisture--dry in all parts between depths of 10 to 30 cm 75 to 90 consecutive days after summer solstice
Depth to lithic contact--50 to 100 cm
Thickness of mollic epipedon--25 to 48 cm
Base saturation--50 to 75 percent
Particle-size control section--40 to 80 percent rock fragments; 18 to 30 percent clay
Reaction--6.1 to 7.3

A horizon
Hue--5YR to 10YR
Value--2 or 3 moist, 3 to 5 dry
Chroma--2 or 3 moist or dry
Cobble content in A2 horizon (where present)--15 to 60 percent
Combined thickness--18 to 46 cm

AB horizon (where present)
Hue--5YR to 10YR
Value--3 or 4 moist, 4 or 5 dry
Chroma--3 to 5 moist or dry
Cobble content--15 to 60 percent
Thickness--0 to 30 cm
Organic carbon content--less than 0.6 percent

Bt horizon
Hue--5YR to 10YR
Value--4 or 5 dry, 3 or 4 moist
Chroma--3 to 6 moist or dry
Texture of fine-earth fraction--loam, clay loam
Rock fragment content--40 to 80 percent
Pararock fragment content--0 to 30 percent
Thickness--10 to 30 cm

COMPETING SERIES:
Brassey--no lithic contact within a depth of more than 150 cm
Bullville--50 to 100 cm (moderately deep) to a paralithic contact (granitic rock)
Durst--50 to 80 cm (moderately deep) to a lithic contact (quartzite); rock fragments consisting dominantly of quartzite in particle-size control section; mean annual soil temperature of 4 to 6 degrees C
Fergie--100 to 150 cm (deep) to a lithic contact (basalt)
Fraval--50 to 100 cm (moderately deep) to a paralithic contact (tuff)
Henhoit--no lithic contact within a depth of more than 150 cm; 35 to 75 percent rounded rock fragments consisting dominantly of quartzite and sandstone in particle-size control section
Little Wood--no lithic contact within a depth of more than 150 cm; 55 to 85 cm deep to sandy-skeletal C horizon
Morningstar--no lithic contact within a depth of 100 cm or more
Mulshoe--dry 90 to 110 consecutive days following summer solstice
Sattley--no lithic contact within a depth of 100 cm or more; dry more than 90 consecutive days following summer solstice

GEOGRAPHIC SETTING:
Elevation--730 to 1700 m
Climate--warm, dry summers; cool, moist winters
Mean annual precipitation--460 to 890 mm
Mean January air temperature--about -4 degrees C
Mean July air temperature--about 19 degrees C
Mean annual air temperature--about 6 to 8 degrees C
Growing season (-2 degrees C)--145 to 170 days
Frost-free season (0 degrees C)--70 to 130 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Anatone, Bocker--on mountain side slopes; 25 to 50 cm (shallow) to a lithic contact (basalt)
Bocker--on mountain side slopes; 10 to 25 cm (very shallow) to a lithic contact (basalt)
Jumpe--on mountain side slopes; ochric epipedon; no lithic contact within a depth of more than 150 cm
Loneridge--on mountain side slopes; no lithic contact within a depth of more than 150 cm; no mollic epipedon; clayey-skeletal particle-size class
Sutkin--on mountain side slopes; no lithic contact within a depth of more than 150 cm; no argillic horizon

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately high

USE AND VEGETATION:
Use--livestock grazing, recreation, wildlife habitat, watershed
Vegetation--bluebunch wheatgrass, Junegrass, bitterbrush

DISTRIBUTION AND EXTENT: South-central Washington; MLRA 6; moderate extent

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

SERIES ESTABLISHED: Yakima County, Washington; 1979

REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Mollic epipedon--zone from the surface to a depth of 41 cm
*Argillic horizon--zone from 64 to 91 cm
*Depth to lithic contact--91 cm
*Particle-size control section--zone from 64 to 91 cm

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National Cooperative Soil Survey
U.S.A.