LOCATION ZEN                     WA

Established Series
Rev. VB/KWH/TLA
09/2019

ZEN SERIES

Landscape--basalt plateaus, hills
Landform--hillslopes, ridges, benches
Slope--0 to 45 percent
Parent material--loess and alluvium derived from basalt
Mean annual precipitation--about 255 mm
Mean annual air temperature--about 9 degrees C
Depth class--moderately deep
Drainage class--well drained
Soil moisture regime--aridic
Soil temperature regime--mesic
Soil moisture subclass--xeric

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Calciargidic Argixerolls

TYPICAL PEDON: Zen silt loam in an area of nonirrigated cropland, on a 5-percent, southwest-facing slope at an elevation of 840 m (All textures are apparent field textures.)

Ap--0 to 23 cm; silt loam, brown (10YR 5/3) dry, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular and vesicular pores; 2 percent pumice fragments 0.5 to 2.0 mm in size; slightly acid (pH 6.5); gradual smooth boundary

AB--23 to 38 cm; silt loam, yellowish brown (10YR 5/4) dry, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine roots; common fine tubular and vesicular pores; 2 percent pumice fragments 0.5 to 2.0 mm in size; neutral (pH 7.2), clear smooth boundary

Bt--38 to 69 cm; silt loam, yellowish brown (10YR 5/4) dry, brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, firm, slightly sticky and slightly plastic; few very fine and fine roots; few fine and very fine vesicular pores; 5 percent pebbles; 2 percent durinodes; trace of sand-sized pumice fragments; common faint clay films on faces of peds; slightly alkaline (pH 7.8), clear smooth boundary

Btk--69 to 91 cm; loam, yellowish brown (10YR 5/4) dry, brown (10YR 4/3) moist; moderate medium subangular blocky structure; very hard, firm, slightly sticky and slightly plastic; few very fine roots; common fine and medium vesicular and irregular pores; 5 percent pebbles; 2 percent durinodes; many distinct clay films on faces of peds; few fine irregular masses of lime; strongly effervescent; moderately alkaline (pH 8.0), abrupt wavy boundary

2R--91 cm; basalt; thin coatings of lime

TYPE LOCATION: Douglas County, Washington, about 19.3 km south of Waterville; about 400 m north and 400 m east of the southwest corner of section 23, T. 23 N., R. 22 E.; latitude 47 degrees, 28 minutes, 10 seconds north and longitude 120 degrees, 2 minutes, 25 seconds west

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--10 to 11 degrees C
Moisture control section--usually dry 105 to 120 cumulative days when the soil temperature is higher than 5 degrees C
Thickness of mollic epipedon--25 to 50 cm
Particle-size control section--averages 22 to 28 percent clay, 5 to 15 percent coarse fragments, and more than 15 percent sand coarser than very fine sand
Content of sand-sized pumice fragments in solum--1 to 5 percent
Depth to secondary carbonates--35 to 75 cm
Calcium carbonate equivalent--3 to 15 percent
Depth to bedrock--50 to 100 cm

Ap or A horizon
Value--4 or 5 dry, 3 or 4 moist
Chroma--2 or 3 dry or moist
Reaction--6.1 to 7.8
Thickness of Ap horizon--15 to 25 cm

AB horizon
Value--4 or 5 dry, 3 or 4 moist
Chroma--2 or 3 moist, 3 or 4 dry
Reaction--6.6 to 7.8
Thickness--10 to 18 cm

Bt horizon
Value--4 to 6 dry, 3 or 4 moist
Chroma--3 or 4 dry or moist
Reaction--6.6 to 8.4
Texture--silt loam, silty clay loam, clay loam
Coarse fragment content--0 to 5 percent
Thickness--10 to 36 cm

Btk horizon
Value--4 to 6 dry, 3 to 5 moist
Chroma--3 or 4 dry or moist
Reaction--7.4 to 9.0
Texture--silt loam, loam, clay loam, silty clay loam, gravelly loam
Coarse fragment content--5 to 20 percent
Thickness--15 to 25 cm

COMPETING SERIES:
Axford--100 to 150 cm (deep) to a paralithic contact (basalt)
Babbington, Drybed, Haw--no lithic contact within a depth of more than 150 cm
Bamos--Bt horizon that is more than 5 percent rock fragments
Benway--100 to 150 cm or more (deep, very deep) to an indurated duripan
Brogan, Polly--no lithic contact within a depth of more than 150 cm (very deep)
Caliralls--100 to 150 cm or more (deep, very deep) to a lithic contact (basalt)

GEOGRAPHIC SETTING:
Elevation--460 to 1000 m
Mean annual precipitation--230 to 310 mm
Climate--semiarid; warm, dry summers; cool, moist winters
Mean January air temperature--about -3 degrees C
Mean July air temperature--about 22 degrees C
Mean annual air temperature--about 9 to 10 degrees C
Frost-free season--130 to 180 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Alstown--on plateaus; less than 18 percent clay in particle-size control section; 50 to 100 cm (moderately deep) to a duripan
Argabak--10 to 30 cm (very shallow, shallow) to a lithic contact (basalt)
Bakeoven--10 to 25 cm (very shallow) to a lithic contact (basalt)
Benwy--on hills; 100 to 150 cm or more (deep, very deep) to an indurated duripan
Lickskillet--on plateaus; 30 to 50 cm (shallow) to a lithic contact (basalt, rhyolite)
Horseflat--on hillslopes; more than 35 percent coarse fragments; 30 to 50 cm (shallow) to a lithic contact (basalt)
Ralls--on hills; 100 to 150 cm or more (deep, very deep) to a lithic contact (basalt)
Renslow--on hills; 100 to 150 cm or more (deep, very deep) to a lithic contact or duripan
Willis--on uplands; 50 to 100 cm (moderately deep) to an indurated duripan; less than 18 percent clay in particle-size control section

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

USE AND VEGETATION:
Use--production of nonirrigated small grain, livestock grazing, watershed, wildlife habitat
Native vegetation--bluebunch wheatgrass, Sandberg bluegrass, Wyoming big sagebrush

DISTRIBUTION AND EXTENT: Central Washington; MLRA 8; moderately extent

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

SERIES ESTABLISHED: Chelan County, Washington; 1968

REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Mollic epipedon--zone from the surface to a depth of 38 cm
*Argillic horizon--zone from 38 to 91 cm
*Secondary carbonates--zone from 69 to 91 cm
*Depth to lithic contact--91 cm
*Particle-size control section--zone from 38 to 88 cm

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National Cooperative Soil Survey
U.S.A.