LOCATION KACHESS WATentative Series
TAXONOMIC CLASS: Ashy-skeletal, amorphic Andic Haplocryods
TYPICAL PEDON: Kachess gravelly ashy sandy loam under a coniferous forest on a 9 percent south facing slope at an elevation of 2,440 feet. The soil was moist when described. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures).
0i--0 to 2 inches; fresh and slightly decomposed forest litter; abrupt smooth boundary. (1 to 3 inches thick)
E--2 to 3 inches; dark grayish brown (10YR 4/2) gravelly ashy sandy loam (volcanic ash) light gray (10YR 6/1) dry; massive; soft, very friable, nonsticky and nonplastic; common fine and medium roots; 15 percent gravel; strongly acid (pH 5.2); abrupt smooth boundary. (1 to 2 inches thick)
Bs--3 to 5 inches; dark brown (7.5YR 3/4) gravelly ashy sandy loam, (dominated by volcanic ash) brown (7.5YR 5/4) dark brown (7.5YR 4/4) dry; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; weakly smeary; common fine and medium roots; 15 percent gravel; NaF pH 12.0; moderately acid (pH 5.6); abrupt smooth boundary. (1 to 4 inches thick)
Bw1--5 to 10 inches; dark yellowish brown (10YR 3/4) gravelly ashy sandy loam (dominated by volcanic ash) yellowish brown (10YR 5/4) dry; moderate fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; weakly smeary; common fine, medium and few coarse roots; 25 percent gravel; NaF pH 12.0; moderately acid (pH 6.0); gradual wavy boundary. (5 to 9 inches thick)
Bw2--10 to 21 inches; dark brown (7.5YR 3/4) very gravelly ashy loam, yellowish brown (10YR 5/4) dry; weak fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; weakly smeary; common very fine and fine roots; 35 percent gravel and 10 percent cobbles; NaF pH 12.0; slightly acid (pH 6.2); gradual wavy boundary (10 to 12 inches thick)
Bw3--21 to 30 inches; dark yellowish brown (10YR 3/4) very cobbly ashy loam, yellowish brown (10YR 5/4) dry; weak medium subangular blocky structure; soft, very friable, nonsticky and slightly plastic; weakly smeary; few very fine roots; 25 percent gravel, 25 percent cobbles; NaF pH 12.0; moderately acid (pH 6.0); clear wavy boundary. (8 to 14 inches thick)
2C1--30 to 39 inches; light olive brown (2.5Y 5/4) extremely cobbly ashy sandy loam, olive brown (2.5Y 4/4) moist; massive in place when disturbed single grain; loose, nonsticky and nonplastic; weakly smeary; few very fine roots; 50 percent gravel and 20 percent cobbles; NaF pH 10.0; moderately acid (pH 6.0); clear wavy boundary. (0 to 12 inches thick)
3C2--39 to 62 inches; light olive brown (2.5Y 5/4) extremely cobbly loamy sand, olive brown (2.5Y 4/4) moist; massive in place when disturbed single grain; loose nonsticky and nonplastic; 55 percent gravel and 25 percent cobbles; NaF pH 10.0; moderately acid (pH 5.8).
TYPE LOCATION: Kittitas County, Washington; about 2 miles east of Keechelus Dam; 1,500 feet west and 2,250 feet south of the northeast corner sec. 14, T. 21 N., R 12 E., W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 40 to 44 degrees F. The soils are usually moist but are dry in all parts in the moisture control section for 30 to 45 consecutive days during summer and fall. Solum thickness ranges from 26 to 38 inches. The exchange complex is dominated by amorphous material in the particle-size control section. It has an estimated moist bulk density of 0.6 to 1.2 g/cc, volcanic glass content of 30 to 60 percent, acid-oxalate extractable aluminum plus one-half iron of greater than 2.0 percent, and 15-bar moisture retention of 10 to 12 percent. Thickness of the spodic horizon ranges from 1 to 4 inches.
The E horizon as a value of 5 or 6 dry, 3 or 4 moist and a chroma of 1 or 2 dry. It is massive or single grain. It is very strongly acid or strongly acid.
The Bs horizon has a hue of 7.5YR or 10YR, value of 4 or 5 dry, 3 or 4 moist and chroma of 4 or 6 dry. It averages 15 to 20 percent gravel and 0 to 5 percent cobbles. It is strongly acid or modertely acid.
The Bw1 horizon has a value of 3 or 4 moist, and chroma of 4 or 6 dry. It averages 15 to 20 percent gravel and 0 to 5 percent cobbles. It is strongly acid or moderately acid.
The Bw2 and Bw3 horizons have a hue of 7.5YR or 10YR. It is very gravelly ashy loam or very cobbly ashy loam. It averages 25 to 35 percent gravel and 10 to 25 percent cobbles. It is strongly acid to slightly acid.
The 2C and 3C horizons have a hue of 10YR or 2.5Y, average 45 to 55 percent gravel and 15 to 25 percent cobbles, and are strongly acid or moderately acid. The 2C horizon is extremely cobbly ashy sandy loam or extremely gravelly ashy sandy loam.
COMPETING SERIES: These are the Gilpar, Polallie (T), Ronsel (T), Thetis (T), Vabus and Waptus (T) soils. Vabus and Waptus soils have densic materials at a depth of 20 to 40 inches. Polallie soils have a lithic contact at 20 to 40 inches. Gilpar soils have a dry value of 6 in the BC horizon and are dominated by angular andesite and pyroclastic rock fragments in the particle-size control section. Lemah soils have a spodic horizon 1 to 3 inches thick. Ronsel soils have a solum thickness of 8 to 26 inches and a spodic horizon 4 to 8 inches thick and are dominated by angular serpentinized basalt rock fragments in the particle-size control section. Thetis soils are dry 15 to 30 days in the moisture control section.
GEOGRAPHIC SETTING: Kachess soils are on glacial valley floors and toeslopes. Slopes are 5 to 25 percent. They formed in ablation glacial till over glacial-fluvial deposits with an admixture of volcanic ash. Elevations are 2,100 to 3,200 feet. The soils are in a marine influenced climate with relatively cool dry summers and cool wet winters. The average annual precipitation is 50 to 80 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 38 to 43 degrees F. The growing season at 28 degrees F is 130 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the proposed Kladnick and Roxer soils and the competing Gilpar, Thetis and Vabus soils. Kladnick soils are frigid, sandy-skeletal and are on outwash terraces. Roxer soils are frigid, lack a spodic horizon and are on mountainsides.
DRAINAGE AND PERMEABILITY: Well drained; permeability is moderate in the subsoil and moderately rapid in the substratum.
USE AND VEGETATION: Used for timber production, summer homesites, recreation and wildlife habitat. Native vegetation is Douglas-fir, western hemlock, and Pacific silver fir, with an understory of western brackenfern, huckleberry and pachystima.
DISTRIBUTION AND EXTENT: East slopes of the Cascade Mountains in northwestern Kittitas County, Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Kittitas County, Washington, 1981.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Albic horizon - the zone from 2 to 3 inches (E horizon)
Spodic horizon - the zone from 3 to 5 inches (Bs horizon)
Andic properties - the zone from 3 to 39 inches
Further investigation is needed as to the 10YR hue with chroma of 4 to 6 within the spodic horizon range of characteristics. These colors do not meet the definition of spodic materials.
This series is very similar to the Thetis soil. Further consideration will be given to correlation of Thetic to Kachess.
Depths to diagnostic horizons and features are measured from the top of the first mineral layer.