LOCATION CLAYTON WAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, isotic, mesic Vitrandic Haploxerepts
TYPICAL PEDON: Clayton ashy fine sandy loam - woodland. (Colors are for moist soil unless otherwise noted.)
Ap1--0 to 5 inches; brown (10YR 5/3) ashy fine sandy loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, nonsticky, and nonplastic; few fine and common very fine roots; few fine and common very fine tubular pores; 1 percent gravel; moderately acid (pH 5.6); abrupt smooth boundary.
Ap2--5 to 8 inches; brown (10YR 5/3) ashy fine sandy loam, dark brown (10YR 3/3) moist; moderate coarse subangular blocky structure; slightly hard, very friable, nonsticky, and nonplastic; few fine, medium and common very fine roots; common very fine tubular pores; 1 percent gravel; moderately acid (pH 5.8); abrupt wavy boundary.
E&Bt1--8 to 29 inches; 95 percent pale brown (10YR 6/3) sandy loam (E part ) brown (10YR 4/3) moist; moderate thick platy structure; slightly hard, very friable, nonsticky, and nonplastic; 5 percent continuous lamellae, brown (7.5YR 4/4) sandy loam (Bt part), brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few fine, common very fine and medium roots; few fine and common very fine tubular pores; 1 percent gravel; slightly acid (pH 6.3); abrupt wavy boundary.
E&Bt2--29 to 42 inches; 85 percent pale brown (10YR 6/3) sandy loam (E part), brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky, and nonplastic; 15 percent continuous lamellae, brown (7.5YR 5/4) sandy loam (Bt part), brown (10YR 4/3) moist; moderate very thick platy structure; moderately hard, friable; nonsticky, and nonplastic; 25 percent continuous faint clay bridging between sand grains; few very fine, fine, medium, and coarse roots; common very fine tubular and interstitial pores; 2 percent gravel; slightly acid (pH 6.4); abrupt wavy boundary.
E&Bt3--42 to 52 inches; 80 percent pale brown (10YR 6/3) loamy sand (E part), brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky, and nonplastic; 20 percent continuous lamellae, brown (7.5YR 5/4) sandy loam (Bt part), brown (10YR 4/3) moist; moderate very thick platy structure; moderately hard, friable, nonsticky, and nonplastic; 15 percent continuous faint clay bridging between sand grains; few very fine, fine, and medium roots; common very fine interstitial and tubular pores; 10 percent gravel and 2 percent cobbles; neutral (pH 6.7); abrupt wavy boundary.
C--52 to 62 inches; 40 percent pale brown (10YR 6/3) and 60 percent very pale brown (10YR 7/3) loamy fine sand, 40 percent brown (10YR 4/3) and 60 percent yellowish brown (10YR 5/4) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; common very fine interstitial pores; 1 percent gravel; neutral (pH 6.8).
TYPE LOCATION: Spokane County, Washington; About 7.5 miles southeast of Deer Park; about 425 feet west and 1,350 feet north of the southeast corner of Section 7, Township 27 N, Range 43 E. USGS Dartford Quad; (Latitude 47 degrees, 50 minutes, 56.73 seconds N and Longitude 117 degrees, 24 minutes, 42.88 seconds W.) NAD83.
RANGE IN CHARACTERISTICS: (Depths to diagnostic horizons or features are measured from the top of the first mineral layer). These soils are usually moist, but are dry in all parts between depths of 8 and 24 inches for 60 to 75 consecutive days in the summer and autumn. The average annual soil temperature is estimated to be 47 to 49 degrees F. The soil is neutral to moderately acid. Rock fragments range from 0 to 15 percent. The particle-size control section has 4 to 12 percent clay and more than 15 percent particles coarser than very fine sand. Depth to the base of the 2E&Bt horizon is 30 inches or more. Depth to loamy fine sand texture is at least 25 inches and commonly is 30 inches or more. The upper 10 to 20 inches has an estimated moist bulk density of 1.20 to 1.50 g/cc, volcanic glass content of 5 to 20 percent, acid oxalate extractable aluminum plus one-half iron of 0.4 to 1.0 percent, 15 bar water retention of 5 to 10 percent (air dry), and a field estimated clay content of 4 to 10 percent. All horizons between a depth of 10 to 30 inches have a base saturation (ammonium acetate) of more than 60 percent.
The A horizon has hue of 10YR or 7.5YR and chroma of 2 to 4 moist. The Ap horizon in cultivated areas has chroma of 2 or 3 and meets mollic criteria in the top 4 to 9 inches. It has weak fine granular structure or weak fine or medium subangular blocky structure.
The Bw horizon, when present, has hue of 10YR or 7.5YR, value of 4 to 6 dry, 3 or 4 moist and chroma of 3 or 4. Texture is fine sandy loam, sandy loam, or loam. It has weak fine or weak medium subangular blocky structure.
Some pedons in cultivated areas have an Ap horizon in place of the Bw horizon.
The E part of the E&Bt horizon has hue of 2.5Y or 10YR, value of 5 or 6 dry, 3 or 4 moist and chroma of 3 or 4. Texture is fine sandy loam, sandy loam, or loamy fine sand.
The Bt part of the E&Bt horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry and chroma of 3 or 4 moist. It consists of lamellae bands of loam, fine sandy loam, or sandy loam 1/16 to 1 1/2 inches in thickness. Combined thickness of the lamellae is less than 6 inches.
Some pedons have a separate E horizon above the E&Bt horizon.
COMPETING SERIES: These are the Kartar and Nevat series. The Bestrom, Cassolary, Hudnut, Koerling, Koseth, and Scala series have similar classification with mixed mineralogy. Kartar soils have 15 to 35 percent rock fragments (wt. average) and are dry for 75 to 90 consecutive days. Nevat soils are 40 to 60 inches to a lithic contact and are dry for 45 to 60 consecutive days. Bestrom soils are 20 to 40 inches to a lithic contact. Cassolary soils have aquic conditions with chroma of 2 and redox concentrations within 20 inches and lack lamellae. Hudnut soils have 15 to 35 percent rock fragments in the particle-size control section and are dry for 75 to 90 consecutive days. Koerling soils have 2Bk horizons (calcareous lake sediments) with sandy loam to silty clay loam textures at a depth of 24 to 40 inches. Koseth soils have 15 to 35 percent rock fragments in the particle-size control section and calcareous loamy-skeletal glacial till in the lower 2C horizon. Scala soils are dry for 75 to 90 consecutive days.
GEOGRAPHIC SETTING: Clayton soils are on glacialfluvial and lake terraces at elevations of 1,800 to 2,250 feet. Slopes range from 0 to 25 percent. These soils formed in moderately coarse mixed glaciofluvial deposits mixed with loess and vocanic ash in the upper part. The climate is characterized by warm, dry summers and cool, moist winters. Average January temperature is 23 degrees F, average July temperature is 67 degrees F. The average annual temperature is 45 to 47 degrees F. The average annual precipitation is 18 to 22 inches. The frost-free period is 100 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bisbee, Bonner, Eloika, Hagen, Laketon, Phoebe, and Wolfeson soils. Bisbee soils are sandy and are on dunelike terraces. Bonner soils are ashy over sandy-skeletal and are on terraces. Eloika soils are ashy over loamy and are on terraces. Phoebe soils have a mollic epipedon and are on outwash terraces. Wolfeson soils have mottles and are saturated within 30 inches of the soil surface and are on lake terraces.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: These soils are used mainly for cropland. Small grains, alfalfa and grass are the principal crops. Some areas are used for hay and pasture. Native vegetation is Douglas-fir, ponderosa pine, and western larch, and a few lodgepole pine and western white pine, with an understory of pinegrass, common snowberry, Oregon-grape, strawberry, rose, kinnikinnick, longtube twinflower, and huckleberry.
DISTRIBUTION AND EXTENT: Northeastern Washington and northern Idaho; MLRA 43, 44. The series is moderate in extent.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Stevens County, Washington, 1913.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 2 to 9 inches (A horizon)
Cambic horizon - the zone from 9 to 20 inches (Bw horizon)
Vitrandic feature - the zone from 2 to 20 inches (A and Bw horizons)
Lamellae - the zone from 20 to 62 inches (E&Bt horizons)
Particle-size control section - the zone from 12 to 42 inches (part of the Bw horizon, the E&Bt1 horizon, and the upper part of the E&Bt2 horizon
The classification of this series has been revised as of 5/00 from coarse-loamy, mixed, mesic Vitrandic Xerochrepts to coarse-loamy, mixed, superactive, mesic Vitrandic Haploxerepts based on revision to Soil Taxonomy.
Lab data for Clayton series, pedon numbers 40A1033 and 40A1034 used to confirm base saturation of greater than 60 percent. Ongoing soil temperature data is being collected for this series to confirm soil temperature regime for Spokane County. Based on vegetation, this area is borderline mesic and possibly frigid.
Mineralogy changed to isotic 10/01.
The 10/03 update reflects a move in the type location to a mesic location in Spokane County. The type location in Stevens county is frigid and will be correlated to the Stapaloop series.