LOCATION SAYDAB WAEstablished Series
TAXONOMIC CLASS: Ashy-skeletal, mixed Oxyaquic Vitricryands
TYPICAL PEDON: Saydab cobbly ashy loam - forested. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures.)
Oe--0 to 1 inch; partially decomposed forest litter. (1 to 3 inches thick)
A1--1 to 3 inches; brown (10YR 5/3) cobbly ashy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; weakly smeary; few very fine roots; common very fine irregular pores; 10 percent gravel and 10 percent cobbles; NaF pH 9.5; moderately acid (pH 5.8); abrupt smooth boundary. (2 to 5 inches thick)
A2--3 to 10 inches; brown (10YR 5/3) gravelly ashy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, sightly sticky andslightly plastic; weakly smeary; common very fine few coarse roots, common very fine interstitial pores; 15 percent gravel; NaF pH 9.5; moderately acid (pH 5.6); clear smooth boundary. (0 to 9 inches thick)
Bw1--10 to 17 inches; yellowish brown (10YR 5/4) very gravelly ashy loam, dark brown (10YR 3/3) moist weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; weakly smeary; few fine, medium, and coarse roots; many very fine irregular pores; 30 percent gravel and 5 percent cobbles; few fine light yellowish brown (10YR 6/4) and yellowish brown (10YR 5/6) moist, redox concentrations; NaF pH 8.6; strongly acid (pH 5.5); clear smooth boundary. (4 to 12 inches thick)
Bw2--17 to 27 inches; light yellowish brown (10YR 6/4) very cobbly ashy loam, brown (10YR 4/3) moist;; weak medium subangular blocky structure; soft, very friable, slightly sticky,and slightly plastic; weakly smeary; few fine, medium and common very fine roots; many very fine irregular pores; 30 percent gravel and 25 percent cobbles; common fine distinct brownish yellow (10YR 6/6) and brown (7.5YR 4/4) moist, redox concentrations; NaF pH 8.5; strongly acid (pH 5.4); abrupt smooth boundary. (8 to 14 inches thick)
R--27 inches; basalt.
TYPE LOCATION: Kittitas County, Washington; about 3 miles northwest of Colockum Pass; 1,350 feet west and 1,600 feet north of the southeast corner section 15, T. 20 N., R. 20 E.; USGS Colockum Pass, Washington topographic quadrangle; Latitude 47 degrees, 13 minutes, 25 seconds N. and Longitude 120 degrees, 18 minutes, 24 seconds W. (NAD 83).
RANGE IN CHARACTERISTICS: These soils are usually moist, but are dry for 45 to 60 consecutive days following summer solstice. Depth to lithic contact ranges from 20 to 40 inches. The mean annual soil temperature 41 to 44 degrees F. The particle-size control section has an estimated moist bulk density of 0.85 to 1.10 g/cc, volcanic glass content of 20 to 30 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 1.0 to 2.0 percent, 15-bar water retention of 5 to 12 percent and 35 to 60 percent angular basalt gravel, cobbles and stones. Depth to redox concentrations is 9 to 30 inches. The umbric epipedon is 10 to 20 inches thick.
The A horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry and moist. Texture of the A1 horizon is cobbly ashy loam or extremely stony ashy loam. Texture of the A2 horizon is gravelly ashy loam or gravelly ashy silt loam. Reaction is moderately acid or slightly acid.
The Bw horizon has hue of 10YR or 7.5YR, value of 5 to 7 dry, 3 or 4 moist and chroma of 3 or 4 dry or moist. Texture of the Bw1 horizon is very gravelly ashy loam, gravelly ashy loam or gravelly ashy silt loam. Texture of the Bw2 horizon is very cobbly ashy loam or very cobbly ashy silt loam. Reaction is strongly acid to slightly acid.
Some pedons have a thin C horizon with value of 5 to 7 dry, 3 or 4 moist and chroma of 3 or 4 dry or moist.
COMPETING SERIES: There are no competing series. The Azwell, Bagmont and Naxing series have a similar classification. All these soils lack a perched water table. In addition, Bagmont soils are 20 to 40 inches deep to paralithic contact. Naxing, soils are more than 60 inches to bedrock.
GEOGRAPHIC SETTING: Saydab soils are on smooth mountain summits and mountain side slopes. Slopes are 0 to 30 percent. These soils formed in mixed material derived from basalt, volcanic ash and loess. Elevation ranges from 5,500 to 7,000 feet. The climate is characterized by dry summers and moist winters. The average annual precipitation is 20 to 50 inches. The average January temperature is about 22 degrees F. and the average July temperature is about 60 degrees F. The average annual temperature is 39 to 43 degrees F. The growing season at 28 degrees F is 80 to 170 days. The frost-free season is 65 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ganis soils and the competing Naxing soils. Ganis soils are loamy and less than 20 inches deep to a lithic contact.
DRAINAGE AND PERMEABILITY: Moderately well drained with an estimated perched water table at its uppermost limit between January and March; slow or medium runoff; moderate permeability.
USE AND VEGETATION: These soils are used non-commercial woodland, livestock grazing, wildlife habitat, recreation and watershed. Vegetation is lodgepole pine, subalpine fir, Engelmann spruce, western larch, elk sedge, polemonium, and huckleberry.
DISTRIBUTION AND EXTENT: East slopes of the Cascade Mountains in south- central Washington; MLRA 6. This series is of small extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Yakima County, Washington, 1979.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Umbric epipedon - the zone from the mineral surface to 17 inches
Cambic horizon -the zone from 17 to 27 inches
Lithic contact - the zone beginning at 26 inches.
Particle-size control section - the zone from 1 to 27 inches with 1 to 10 inches qualifying as ashy and 10 to 27 inches qualifying as ashy-skeletal. The family class of ash-skeletal is based on the thickest zone between 1 and 27 inches.
Oxyaquic feature - from 9 to 27 inches having saturation from perched water table but no aquic conditions (reduction).
Depths to diagnostic horizons and features are measured from the top of the first mineral layer.
Classification revision 3/99 from medial-skeletal Andic Cryumbrepts to ashy-skeletal, glassy Humic Xeric Vitricryands.
Classification revision 3/02 from ashy-skeletal, glassy Humic Xeric Vitricryands to ashy-skeletal, mixed Aquic Vitricryands based on lab data from the associated Naxing series and from the presence of redox concentrations within 100 cm.
Classification revision 7/06 from Aquic Vitricryands to Oxyaquic Vitricryands based on presence of perched water table with redox concentrations within 100 cm and no aquic conditions (reduction).