LOCATION TRELK WAEstablished Series
TAXONOMIC CLASS: Fine-loamy, isotic, mesic Andic Haploxeralfs
TYPICAL PEDON: Trelk ashy loam - forested, on a 2 percent slope at an elevation of 1,760 feet. (Colors are for dry soil unless otherwise noted. All textures are apparent field textures.)
Oi--0 to 0.5 inches; slightly decomposed needles and twigs.
Oa--0.5 to 1 inches; highly decomposed organic material.
A1--1 to 6 inches; brown (7.5YR 5/4) ashy loam, dark brown (7.5YR 3/4) moist; weak fine granular structure; soft, very friable, slightly sticky, slightly plastic and weakly smeary; many very fine and fine and common medium roots; many fine irregular pores; few gravel; neutral (pH 6.8); gradual smooth boundary. (2 to 8 inches thick)
A2--6 to 11 inches; brown (7.5YR 5/4) ashy loam, dark brown (7.5YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky, slightly plastic and weakly smeary; common very fine and fine and few medium roots; common fine irregular and tubular pores; 5 percent gravel; neutral (pH 6.8); clear smooth boundary. (5 to 10 inches thick)
2BA--11 to 18 inches; light brown (7.5YR 6/4) loam, brown (7.5YR 4/4) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common fine irregular and few fine tubular pores; 5 percent gravel; neutral (pH 6.8); gradual wavy boundary. (7 to 11 inches thick)
2Bt--18 to 34 inches; brown (7.5YR 5/4) loam, brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and slightly plastic; few fine and medium and common very fine roots; common fine irregular and tubular pores; common faint clay films on faces of peds and in pores; 10 percent gravel and 5 percent paragravel; neutral (pH 6.8); gradual smooth boundary. (12 to 17 inches thick)
2C--34 to 61 inches; brown (7.5YR 5/4) gravelly loam, brown (7.5YR 4/4) moist; massive; slightly hard, firm, slightly sticky and slightly plastic; few very fine and fine roots; common fine irregular and few fine tubular pores; 15 percent gravel and 10 percent paragravel; slightly acid (pH 6.4).
TYPE LOCATION: Klickitat County, Washington; about 6 miles east of Glenwood; about 50 feet north and 2,550 feet east of the southwest corner, section 10, T. 6 N., R. 13 E. (Latitude 46 degrees, 00 minutes, 57 seconds N. and Longitude 121 degrees, 10 minutes, 03 seconds W.)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 49 degrees F. The soil moisture control section is dry in all parts for 60 to 75 consecutive days within the four months that follow the summer solstice in 6 or more years out of 10. Volcanic ash influence is 7 to 14 inches thick and has an estimated moist bulk density of 0.80 to 0.90 g/cc, volcanic glass content of 30 to 60 percent, acid oxalate extractable aluminum plus one-half iron of 1.0 to 2.0 percent, phosphate retention of 50 to 75 percent, and 15-bar water retention of 8 to 12 percent. The particle-size control section has 18 to 33 percent clay, 0 to 20 percent gravel and 0 to 10 percent paragravel. Reaction ranges from moderately acid to neutral throughout.
The A horizon has hue of 5YR or 7.5YR and chroma of 3 or 4 dry or moist. Texture is ashy loam or gravelly ashy loam.
The 2Bt horizon has value of 3 or 4 moist, 5 or 6 dry and chroma of 4 to 6 dry or moist. Texture is loam, clay loam or gravelly loam.
A 2BCt horizon is present in some pedons.
The 2C horizon has chroma of 4 to 6 dry. Texture is loam or gravelly loam.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Trelk soils are on terraces at elevations of 1,300 to 3,200 feet. Slopes are 2 to 30 percent. Trelk soils formed in alluvium derived from basalt mixed with volcanic ash in the surface. Summers are warm and dry; winters are cool and moist, with snow cover from December through April. The mean annual precipitation is 30 to 35 inches. The average January temperature is 25 degrees F. and the average July temperature is 63 degrees F. The mean annual temperature is 45 to 47 degrees F. The frost-free season is 90 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the McCumber, Pinbit, and Yedlick soils. McCumber soils are on foot slopes and are ashy-skeletal. Pinbit soils are on terraces and are ashy. Yedlick soils are on mountains and are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: These soils are used for timber production, livestock grazing, and wildlife habitat. Native vegetation is ponderosa pine, Douglas-fir, and Oregon white oak with an understory of pinegrass, common snowberry, snowbrush ceanothus, squawcarpet, kinnikinnick, creambush oceanspray and rose.
DISTRIBUTION AND EXTENT: East slopes of the Cascade Mountains in western Klickitat and Yakima Counties, Washington. MLRA 6. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Klickitat County, Washington, 2003.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 1 to 11 inches
Argillic horizon - the zone from 18 to 34 inches
Andic feature - the zone from 1 to 11 inches
Particle- size control section - the zone from 18 to 34 inches
Depth to diagnostic horizons and features are measured from the top of the first mineral layer.