LOCATION YRTNEG WATentative Series
TAXONOMIC CLASS: Loamy, mixed, superactive, mesic Lithic Argixerolls
TYPICAL PEDON: Yrtneg loam - cultivated, on a 6 percent south-facing slope at an elevation of 2,670 feet. (colors are for dry soil unless otherwise stated.)
Ap--0 to 7 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; moderate fine and medium subangular blocky structure parting to moderate fine and medium granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine irregular pores; 5 percent pebbles; neutral (pH 6.8); abrupt smooth boundary. (5 to 7 inches thick)
AB--7 to 10 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; moderate fine, medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; common very fine irregular pores; 5 percent pebbles; neutral (pH 6.8); abrupt smooth boundary. (3 to 8 inches thick)
2Bt1--10 to 16 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist, moderate medium subangular blocky structure; hard, firm, slightly sticky and moderately plastic; common very fine roots; common very fine irregular and common very fine tubular pores; few faint pressure faces on peds and few faint clay bridging in pores; 15 percent pebbles concentrated at upper boundary; 10 percent very coarse cylindrical cicada cast; 5 percent pebbles; neutral (pH 7.0); clear wavy boundary.
2Bt2--16 to 19 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist, moderate fine and medium subangular blocky structure; hard, firm, slightly sticky and moderately plastic; common very fine roots; few very fine irregular and many very fine tubular pores; few faint pressure faces on peds, few faint clay bridging in pores and common distinct clay films on rock fragments; 5 percent pebbles and 5 percent cobbles; neutral (pH 7.0); abrupt irregular boundary. (Combined thickness of the 2Bt horizon is 4 to 11 inches)
3R--19 inches; fractured basalt with silica coatings over 30 percent of the surface area.
TYPE LOCATION: Kittitas County, Washington, about 7 miles south of Ellensburg; about 800 feet east and 2,300 feet south of the northwest corner of section 3, T. 16 N., R. 18 E.; USGS Ellensburg South, Wash. topographic quadrangle; Latitude 46 degrees, 54 minutes, 21 seconds N. and Longitude 120 degrees, 33 minutes, 35 seconds W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at lithic contact is 47 to 54 degrees F. These soils are usually moist but are dry in all parts of the moisture control section for 90 to 100 consecutive days following the summer solstice. Thickness of the mollic epipedon is 12 to 20 inches and includes all of the argillic horizon. The upper 8 to 15 inches has an estimated bulk density of 1.10 to 1.30 g/cc, volcanic glass content of 5 to 20 percent, acid oxalate extractable aluminum plus one-half of the acid oxalate extractable iron of 0.4 to 0.7 percent, and 15-bar water retention of 5 to 10 percent for air dried samples. The particle-size control section averages 27 to 33 percent clay in the fine earth fraction, more than 15 percent fine sand or coarser and 5 to 20 percent rock fragments by volume. Organic matter is estimated to range from 2 to 3 percent in the Ap horizon or A1 horizon if present. Solum thickness and depth to lithic contact with basalt is 12 to 20 inches.
The AB horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 or 3 dry.
The 2Bt horizon is neutral or slightly alkaline. The 2Bt2 is a clay loam or gravelly clay loam.
COMPETING SERIES: These are the Adinot, Borland, Jilson, Laric, Malinda, Marlic, McQuarrie, Pass Canyon, and Terca series. Adinot soils are moderately well drained. Borland and Jilson soils have mollic epipedon that are less than 10 inches thick with less than 5 percent volcanic glass. Laric soils have a lithic contact at a depth of 5 to 12 inches. Malinda soils have 35 to 80 percent rock fragments in the A horizon with less than 5 percent volcanic glass. Marlic soils have more than 35 percent clay in the lower part of the argillic horizon and are dry in the moisture control section more than half the time when soil temperature at the lithic is above 40 degrees. McQuarrie soils have secondary carbonates in the particle-size control section and are moderately alkaline. Pass Canyon and Terca soils lack silica accumulation on surface of bedrock, have A horizons with less than 5 percent volcanic glass, and more than 15 percent rock fragments, and have a mollic epipedon 7 to 12 inches thick.
GEOGRAPHIC SETTING: Yrtneg soils are on hillslopes, dissected plateaus and piedmont slopes and have slopes of 3 to 30 percent. These soils formed in loess mixed with volcanic ash in the surface, slope alluvium and some residuum from basalt. Elevations are 2,400 to 2,800 feet. Summers are warm and dry, winters are cool and moist. Average annual precipitation is 12 to 15 inches. Average January temperature is about 25 degrees F. average July temperature is about 69 degrees F. Average annual temperature is 46 to 52 degrees F. The frost-free season is 120 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Argabak, Camaspatch, Mozen and Volinger soils. Argabak soil are on ridgetops and benches and have a lithic contact at a depth of 5 and 10 inches. Camaspatch soils are on hillslopes, ridges, plateaus and structural benches and have 35 to 50 percent clay in particle size control section. Mozen soils are on hillslopes, dissected plateaus and piedmont slopes and have a lithic contact between 25 and 40 inches. Volinger soils are on hillslopes, dissected plateaus and piedmont slopes and have a lithic contact at depths greater than 60 inches.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately slow permeability.
USE AND VEGETATION: Used for livestock grazing, dryland cropland and wildlife habitat. Native vegetation is Sandberg bluegrass, bluebunch wheatgrass, Wyoming big sagebrush and threetip sagebrush.
DISTRIBUTION AND EXTENT: Kittitas County, Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Kittitas County, Washington, 1997. The name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - 0 to 19 inches (Ap, AB, and 2Bt horizons)
Argillic horizon - 10 to 19 inches (2Bt horizon Lakedale-Wisconsin Age soil member)
PSCS - 10 to 19 inches (2Bt horizon)
Vitrandic feature - 0 to 10 inches (Ap and AB horizons)