LOCATION MODSEL WATentative Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Vitrandic Argixerolls
TYPICAL PEDON: Modsel ashy loam - pasture, on a 3 percent south-facing slope at an elevation of 1,950 feet. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 7 inches; dark grayish brown (10YR 4/2) ashy loam; very dark brown (10YR 2/2) moist; moderate fine platy structure parting to moderate fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; few very fine tubular pores; 5 percent gravel; NaF pH 8.5; neutral (pH 7.2); abrupt smooth boundary. (7 to 14 inches thick)
BAt--7 to 10 inches; dark grayish brown (10YR 4/2) clay loam, very dark brown (10YR 2/2) moist; strong fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine roots; common very fine tubular and irregular pores; few faint clay films lining pores and on faces of peds; 5 percent gravel; NaF pH 8.6; neutral (pH 7.2); clear wavy boundary. (3 to 6 inches thick)
Bt1--10 to 16 inches; brown (10YR 5/3) gravelly clay loam, very dark grayish brown (10YR 3/2) moist; strong fine and medium subangular blocky structure; very hard, firm, moderately sticky and moderately plastic; common very fine roots; common very fine tubular pores; few faint clay films on faces of peds and in pores; few distinct very dark gray (10YR 3/1) organic coats on faces of peds; 25 percent gravel and 5 percent cobbles; NaF pH 8.6; neutral (pH 7.2); abrupt wavy boundary. (5 to 14 inches thick)
2Bt2--16 to 20 inches; brown (10YR 5/3) very [SW2]gravelly clay, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; very hard, very firm, very sticky and very plastic; few very fine roots; common very fine and tubular [SW3]pores; few distinct clay films lining pores and on faces of peds; few distinct very dark gray (10YR 3/1) organic coats on faces of peds; 45 percent gravel and 15 percent cobbles; NaF pH 8.6; neutral (pH 7.2); clear wavy boundary. (4 to 8 inches thick)
2Bt3--20 to 37 inches; brown (10YR 5/3) very [SW4]gravelly clay, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; very hard, very firm, moderately sticky and moderately plastic; few very fine roots; common very fine irregular and tubular pores; few distinct clay films on faces of peds and in pores; few distinct very dark gray (10YR 3/1) organic coats on faces of peds; 45 percent gravel and 15 percent cobbles; NaF pH 8.6; neutral (pH 7.2); abrupt smooth boundary. (12 to 24 inches thick)
2Bt4--37 to 56 inches; brown (10YR 5/3) extremely gravelly sandy clay loam, dark brown (10YR 3/3) moist; strong fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few very fine roots; many very fine irregular pores; few distinct clay films on faces of peds and in pores; common distinct strong brown (7.5YR 4/6) iron stains on faces of peds and in pores; few distinct very dark gray (10YR 3/1) organic coats on faces of peds; 40 percent gravel and 25 percent cobbles; NaF pH 8.5; neutral (pH 7.2); clear wavy boundary. (10 to 20 inches)
2Bt5--56 to 60 inches; yellowish brown (10YR 5/4) extremely gravelly sandy clay loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; slightly hard, firm, moderately sticky and moderately plastic; few very fine roots; common very fine irregular pores; few faint clay films on faces of peds and in pores; common fine distinct iron stains on faces of peds and in pores; common distinct very dark gray (10YR 3/1) organic coats on faces of peds; 40 percent gravel and 25 percent cobbles; NaF pH 8.5; neutral (pH 7.2).
TYPE LOCATION: Kittitas County, Washington; about 6 miles north of Ellensburg, about 1,250 feet east and 2,030 feet north of the southwest corner of section 34, T. 19 N., R. 18 E.; USGS Ellensburg North, Washington topographic quadrangle; Latitude - 47 degrees, 05 minutes, 38 seconds N. and Longitude - 120 degrees, 34 minutes, 30 seconds W. (NAD83).
RANGE IN CHARACTERISTICS: The average annual soil temperature at a depth of 20 inches is 47 to 54 degrees F. These soils are usually moist but are dry in the moisture control section for 60 to 75 consecutive days following the summer solstice. Depth to the irrigated-induced water table and aquic conditions is 30 to 40 inches. The mollic epipedon is 30 to 60 inches thick and includes the Bt horizon. The upper 7 to 14 inches has an estimated bulk density of 1.15 to 1.35 grams per cubic centimeter, volcanic glass content of 10 to 20 percent and acid oxalate extractable aluminum plus one-half extractable iron of 0.3 to 0.5 percent. The particle-size control section has 35 to 40 percent clay and averages 15 percent fine sand or coarser. Rock fragments range from 35 to 50 percent by volume. Organic matter is estimated to range from 2 to 4 percent in the Ap and BAt horizons.
The A horizon has value of 3 or 4 dry. Texture is ashy loam or cobbly ashy loam. Reaction is slightly acid or neutral.
The BAt horizon has value of 3 or 4 dry and 2 or 3 moist. Texture is gravelly clay loam or clay loam.
The Bt horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 or 3, dry or moist. Texture is clay loam, gravelly clay loam or cobbly clay loam. [SW5]
The 2Bt horizons have value of 4 or 5 dry, 3 or 4 moist and chroma of 2 to 4, dry or moist. Texture is very gravelly clay, extremely gravelly clay, extremely cobbly clay loam, very gravelly sandy clay, extremely gravelly sandy clay or extremely gravelly sandy clay loam[SW6].
COMPETING SERIES: These are the
Maxhill (T) and
Tanksel series.
Maxhill soils dry for 90 to 100 consecutive days following the summer solstice; lack redox features (oxyaquic conditions)
Tanksel soils dry for 100 to 120 consecutive days following the summer solstice; lack redox features (oxyaquic conditions); 20 to 40 inches to lithic contact (basalt)
GEOGRAPHIC SETTING: Modsel soils are on alluvial fans and have slopes of 0 to 5 percent. These soils formed in alluvium with an influence of volcanic ash in the surface. Elevations are 1,700 to 3,100 [SW7]feet. These soils are in a semiarid climate with warm, dry summers and cool, moist winters. The mean annual precipitation is 12 to 15 inches. The average January temperature is about 25 degrees F. and the average July temperature is about 69 degrees F. The mean annual air temperature is 46 to 52 degrees F. The frost-free season is 130 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Metmill, Reelow, Sketter and Varodale soils. Metmill soils are on alluvial fans and inset fans. Reelow soils are on uplifted fan remnants and fan terraces and are 10 to 20 inches to hardpan. Sketter soils are on uplifted fan remnants and fan terraces and are 20 to 40 inches to hardpan. Varodale soils are on terraces and alluvial fans and have 45 to 65 percent clay in the particle-size control section.
DRAINAGE AND PERMEABILITY: Moderately well drained[SW8]; slow runoff; slow permeability. This soil is irrigated and drained. An irrigated-induced water table is at its uppermost limit during the mid-May to mid-October growing season.
USE AND VEGETATION: These soils are used for crop production, livestock grazing and wildlife habitat.
DISTRIBUTION AND EXTENT: Kittitas County, Washington; MLRA 8, 44. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Kittitas County, Washington, l999. Name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 37 inches (Ap, BAt, Bt1, 2Bt2 and 2Bt3 horizons)
Vitrandic feature - the zone from 0 to 7 inches (Ap horizon)
Argillic horizon - the zone from 7 to 60 inches (BAt, Bt, and 2Bt horizons)
Particle size control section - the zone from 7 to 27 inches (BAt, Bt1, 2Bt2 and part of the 2Bt3 horizons)
Oxyaquic feature - irrigation induced water table at 37 inches for 20 or more consecutive days.