LOCATION SKETTER WATentative Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Vitrandic Durixerolls
TYPICAL PEDON: Sketter gravelly loam- irrigated pasture, on a 3 percent slope at an elevation of 2,250 feet. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 6 inches; very dark grayish brown (10YR 3/2) cobbly loam, black (10YR 2/1) moist; moderate medium subangular structure parting to moderate medium and coarse granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine irregular and common very fine tubular pores; 5 percent pebbles and 15 percent cobbles; NaF pH 8.5; neutral (pH 6.6); abrupt smooth boundary. (4 to 8 inches thick)
BA--6 to 10 inches; very dark grayish brown (10YR 3/2) gravelly loam, black (10YR 2/1) moist; moderate fine and medium subangular structure; hard, friable, slightly sticky and slightly plastic; many very fine roots; common very fine irregular and tubular pores; 30 percent pebbles and 25 cobbles; NaF pH 8.5; neutral (pH 6.6); clear smooth boundary. (3 to 12 inches thick)
2Bt--10 to 21 inches; dark yellowish brown (10YR 4/4) extremely gravelly sandy clay, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine roots; few very fine pores; common distinct dark brown (7.5YR 3/3) clay films lining pores and on faces of peds; 40 percent pebbles and 30 percent cobbles; NaF pH 8.5; neutral (pH 6.8); abrupt smooth boundary. (9 to 20 inches thick)
3Bstqm--21 to 24 inches; very pale brown (10YR 7/3) dense alluvium that breaks to extremely gravelly sandy loam, brown (10YR 5/3) moist; massive; moderately cemented; few very fine roots in vertical seams and many very fine roots concentrated at upper boundary; few very fine pores in seams and around rock fragments and common very fine pores in matrix; common prominent dark brown (7.5YR 4/4) clay films in vertical seams; 1 to 2 mm prominent brown (7.5YR 4/3) concentration at upper boundary; common distinct light yellowish brown (10YR 6/4) coatings around rock fragments; common prominent black (N 2/0) iron-manganese stains around rock fragments, in pores and in seams; 55 percent pebbles and 10 percent cobbles; NaF pH 8.6; neutral (pH 6.8); clear wavy boundary. (1 to 5 inches thick)
3Bsqm--24 to 55 inches; very pale brown (10YR 7/4) dense alluvium that breaks to extremely gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; massive; moderately cemented; few very fine pores in seams and around rock fragments and common very fine and fine pores in matrix; common distinct light yellowish brown (10YR 6/4) coatings around rock fragments; common silica coatings on bottom of rock fragments; common prominent black (N 2/0) iron-manganese stains around rock fragments, in seams and in pores; 50 percent pebbles and 15 percent cobbles; NaF pH 8.0; neutral (pH 6.8); clear wavy boundary. (24 to 49 inches thick)
3Bs--55 to 60 inches; light yellowish brown (2.5Y 6/3) extremely gravelly sandy loam, dark grayish brown (10YR 4/2) moist; massive; weakly cemented; common very fine, fine and medium pores; few prominent black (N 2/0) iron-manganese stains around rock fragments; 59 percent pebbles and 15 percent cobbles; NaF pH 8.0; neutral (pH 7.0)
TYPE LOCATION: Kittitas County, Washington; about 5 miles northeast of Ellensburg; about 800 feet north and 1,800 feet west of the southeast corner of section 34, T. 19 N., R. 19 E.; USGS Colockum Pass SW, Washington; Latitude 47 degrees, 05 minutes, 28 seconds N. and Longitude 120 degrees, 26 minutes, 24 seconds W.
RANGE IN CHARACTERISTICS: Mean annual soil temperature at a depth of 20 inches is 47 to 52 degrees F. These soils are usually moist but are dry in the moisture control section for 90 to 100 consecutive days following the summer solstice. Thickness of mollic epipedon is 20 to 30 inches. The upper 7 to 20 inches has an estimated bulk density of 1.10 to 1.45 b/cc, volcanic glass content of 15 to 25 percent, acid oxalate extractable aluminum plus one-half if acid oxalate iron of 0.25 to 0.6 percent, and 15-bar water retention of 5 to 10 percent for air dried samples. The particle-size control section has 35 to 45 percent clay in the fine earth fraction and 40 to 80 percent rock fragments. Base saturation is more than 75 percent. Organic matter is estimated to range from 2 to 4 percent in the Ap or A horizons. The depth to an extremely or very gravelly moderately cemented iron-silica duripan is 20 to 40 inches. Reaction is slightly acid or neutral throughout.
The Ap or A horizons have value of 3 through 5 dry, and 2 or 3 moist, and chroma of 1 through 3 dry and 1 or 2 moist.
The BA horizon has value of 3 through 5 dry, and 2 or 3 moist, and chroma of 2 or 3 dry or moist. It is gravelly loam or very gravelly loam.
The 2Bt horizon has hue of 7.5YR or 10YR, value of 4 or 5 dry, and 2 or 3 moist, and chroma of 2 through 4 dry or moist. It is very gravelly clay, extremely gravelly sandy clay or very gravelly clay loam.
The 3Bstqm horizon has hue of 7.5YR or 10YR, value of 5 through 7 dry, 4 or 5 moist, and chroma of 3 through 6 dry and 2 through 4 moist. It is very gravelly sandy clay loam, extremely gravelly sandy loam or extremely gravelly sandy clay loam.
The 3Bsqm horizon has value of 5 through 7 dry, 4 or 5 moist, and chroma of 3 through 6 dry and 2 through 4 moist. It is very gravelly sandy clay loam, extremely gravelly sandy loam or extremely gravelly sandy clay loam.
The 3Bs horizon has hue of 10YR or 2.5Y, value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 through 6 dry and 2 through 4 moist. It is very gravelly sandy loam or extremely gravelly sandy loam.
COMPETING SERIES: There are no competing series. A similar soil is Durtash. Durtash soils have lime-silica cemented duripans, are 10 to 20 inches to duripan, are dry for 100 to 120 consecutive days and lack vitrandic feature.
GEOGRAPHIC SETTING: Sketter soils are on old uplifted fan remnants, old terraces and old till plains and have slopes of 2 to 15 percent. These soils formed in alluvium and glacial drift over a duripan with an influence of loess mixed with volcanic ash in the surface. Elevation is 1,700 to 3,100 feet. Climate is semiarid with warm dry summers and cool moist winters. The average annual precipitation ranges from 12 to 16 inches. The average January temperature is about 25 degrees F.; average July temperature is about 69 degrees F., and average annual temperature is about 46 to 50 degrees F. The frost-free season is 130 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lablue, Maxhill, Metser, Millhouse, Reelow and Reeser series. Lablue soils are on old uptifted fan remnants, old terraces old till plains and are 7 to 10 inches to a duripan. Maxhill soils (on terraces and alluvial fans), Metser soils (on terraces and alluvial fans) and Millhouse soils (on alluvial fans) all lack a duripan. Reelow soils are on old uplifted fan remnants, old terraces and old till plains and are 10 to 20 inches to a duripan.
DRAINAGE AND PERMEABILITY: Well drained, slow runoff; moderately slow permeability above the duripan.
USE AND VEGETATION: Used for irrigated crop production, livestock grazing and wildlife habitat. Native vegetation is bluebunch wheatgrass, Wyoming sagebrush and bitterbrush. When irrigated, hay, oats and wheat are among the crops grown.
DISTRIBUTION AND EXTENT: Central Washington. The soil is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Kittitas County, Washington, l999. The name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon (pachic) - 0 to 21 inches (Ap, BA, 2Bt horizons)
Argillic horizon - 10 to 21 inches (2Bt horizon, Swauk and pre-Swauk Prairie, pre-Wisconsin Age soil members)
Duripan - 21 to 55 inches (3Bstqm and 3Bsqm horizons; predominantly of Pliocene Age Thorp Gravel which consists mostly of two facies, mainstream gravel are composed of durable silicic to intermediate volcanic rocks and sidestream gravel consisting mostly of subangular clasts of Grande Ronde Basalt; and Swauk Prairie and Lookout Mountain Ranch, pre-Wisconsin Age glacial drift)
PSCS - zone from 10 to 21 inches (2Bt horizon)
Vitrandic feature - 0 to 10 inches (Ap, BA and 2Bt horizons)
Haplic feature - 21 to 55 inches with a moderately cemented duripan of iron and silica.
Xeric soil moisture regime.
Laboratory data from associated Reelow soil was used to base the lack of a 15 percent (absolute) clay increase at the upper boundary of the argillic horizon.