LOCATION SPEXARTH WAEstablished Series
TAXONOMIC CLASS: Ashy over loamy, glassy over isotic Xeric Vitricryands
TYPICAL PEDON: Spexarth ashy sandy loam under a coniferous forest on a 40 percent northwest facing slope. The soil was dry when described. (Colors are for dry soil unless otherwise stated. Textures are apparent field textures.)
Oi--0 to 1 inch; slightly decomposed forest litter. (1 to 2 inches thick)
A1--1 to 2 inches; light gray (10YR 7/1) ashy sandy loam, grayish brown (10YR 5/2) moist; single grain; soft, very friable, nonsticky and nonplastic; common very fine roots; moderately acid (pH 5.6) abrupt smooth boundary (0 to 2 inches thick)
A2--2 to 5 inches; yellowish brown (10YR 5/4) ashy sandy loam, dark yellowish brown (10YR 3/4) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic, weakly smeary; common very fine and few coarse roots; many very fine and fine irregular pores; 10 percent sandstone paragravel; NaF pH 11.5; moderately acid (pH 5.6); clear wavy boundary. (0 to 5 inches thick)
Bw1--5 to 11 inches; light yellowish brown (10YR 6/4) paragravelly ashy sandy loam, dark yellowish brown (10YR 4/4) moist; weak very fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic, weakly smeary; common fine and medium roots; common very fine and fine irregular pores; 20 percent sandstone paragravel; NaF pH 11.5; moderately acid (pH 5.6); clear wavy boundary. (6 to 7 inches thick)
Bw2--11 to 19 inches; light yellowish brown (10YR 6/4) extremely paracobbly ashy sandy loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic, weakly smeary; common fine, medium, and few coarse roots; common very fine and fine irregular pores; 40 percent sandstone paragravel and 30 percent sandstone paracobbles; NaF pH 11.5; moderately acid (pH 5.6); abrupt wavy boundary. (5 to 14 inches thick)
2BC--19 to 28 inches; light yellowish brown (2.5Y 6/4) very paragravelly sandy loam, olive brown (2.5Y 4/4) moist; massive; soft, very friable, nonsticky and slightly plastic; common fine and few medium roots; common fine irregular pores; 50 percent sandstone paragravel; NaF pH 9.8; strongly acid (pH 5.2); clear wavy boundary. (8 to 12 inches thick)
2Cr--28 inches; weathered sandstone.
TYPE LOCATION: Kittitas County, Washington; about 7 miles southwest of Cle Elum; 1,750 feet west and 1,700 feet south of the northeast corner section 16, T. 19 N., R. 14 E.; USGS Ronald, Washington topographic quadrangle, Latitude 47 degrees, 08 minutes, 12 seconds N. and Longitude 121 degrees, 05 minutes, 54 seconds W.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact is 20 to 40 inches. The mean annual soil temperature is 42 to 45 degrees F. These soils are usually moist but are dry in all parts in the moisture control section for 45 to 60 consecutive days during summer and fall. The upper 15 to 30 inches of the solum has 30 to 70 percent volcanic glass, 0.7 to 2.0 percent acid-oxalate extractable aluminum plus one-half iron, 35 to 70 percent phosphate retention, 5 to 12 percent 15-bar moisture content, and 0.85 to 1.10 grams per cubic centimeter estimated moist bulk density.
The A1 horizon has value of 5 to 7 dry, 3 to 5 moist and chroma of 1 or 2 dry, 2 or 3 moist. Texture is ashy sandy loam or ashy loamy sand. Reaction is moderately acid or strongly acid.
The A2 horizon, when present, has chroma of 3 or 4 moist or dry. It averages 5 to 35 percent paragravel.
The Bw horizon has value of 6 or 7 dry, 3 to 5 moist and chroma of 3 or 4 dry or moist. The Bw1 horizon is ashy sandy loam, ashy fine sandy loam or ashy loam in the fine-earth fraction and has 0 to 20 percent gravel and 10 to 30 percent paragravel. The Bw2 horizon is ashy sandy loam, ashy fine sandy loam, or ashy loam in the fine-earth fraction and has 0 to 20 percent gravel, 20 to 40 percent paragravel and 20 to 30 percent paracobbles. Reaction is moderately acid or strongly acid.
The 2BC horizon has value of 4 or 5 moist and chroma of 3 or 4 dry or moist. Texture is sandy loam or loam in the fine-earth fraction and has 0 to 20 percent gravel, 50 to 60 percent paragravel and 0 to 35 percent paracobbles. Reaction is strongly acid to slightly acid.
COMPETING SERIES: These are the Almac, Codylake, Gahee, Helter, Nile, and Shanahan soils. The Almac, Gahee, Helter, Nile, and Shanahan soils are very deep. The Codylake and Helter soils are deep.
GEOGRAPHIC SETTING: Spexarth soils are on mountain side slopes and ridges. Slopes are 30 to 60 percent. Elevation is 3,600 to 5,400 feet. The soils formed in volcanic ash mixed with colluvium and residuum from Naches and Manastash sandstone. The soft sandstone and siltstone fragments are light yellowish brown 2.5Y 4/4) fresh face with light gray (2.5Y 7/2) weathered surface. Most of the fragments can be broken by hand. The soils are in a climate with cool moist summers and cold wet winters. The mean annual precipitation is 45 to 65 inches. The average January temperature is about 25 degrees F., and the average July temperature is about 61 degrees F. The mean annual temperature is 41 to 43 degrees F. The frost-free season is 40 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ainsley and Terence soils. Ainsley soils are on mountain side slopes and benches, are clayey-skeletal and are very deep. Terence soils are on mountain side slopes, toeslopes, and ridges, are ashy-skeletal and are very deep.
DRAINAGE AND PERMEABILITY: Well drained, runoff is medium to rapid. Permeability is moderately rapid.
USE AND VEGETATION: These soils are used for timber production, wildlife habitat and watershed. Vegetation is Douglas-fir, lodgepole pine, Pacific silver fir, western white pine and western hemlock with an understory of russet buffaloberry, pachystima, Oregon-grape, huckleberry and rusty menziesia.
DISTRIBUTION AND EXTENT: East slopes of the Cascade Mountains in west central Kittitas County, Washington; MLRA 3. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wenatchee National Forest; Kittitas County, Washington, 2003.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon - the zone from 1 to 5 inches (A1 and A2 horizons)
Cambic horizon - the zone from 5 to 19 inches (Bw1 and Bw2 horizons)
Andic soil properties - the zone from 1 to 19 inches
Particle-size control section - the zone from 1 to 28 inches with the zone from 1 to 19 inches qualifying as ashy and the zone from 19 to 28 inches qualifying as loamy.
All depths to diagnostic horizons and features found in the range of characteristics are measured from the top of the first mineral layer.
More investigation needed as to the presence of a udic soil moisture regime based on vegetation listed.
ADDITIONAL DATA: Laboratory data available for a taxadjunct to the Spexarth series, soil survey sample # S91WA-037-002, NSSL, Lincoln, NE.