LOCATION FISCUS WAEstablished Series
TAXONOMIC CLASS: Ashy-skeletal over loamy-skeletal, glassy over isotic Xeric Vitricryands
TYPICAL PEDON: Fiscus ashy sandy loam - forestland, on a 26 percent northeast-facing slope at an elevation of 4,400 feet. (When described on 8/28/91 the soil was dry. Colors are for dry soil unless otherwise stated. All textures are apparent field textures)
Oi--0 to 1 inch; slightly decomposed forest litter mixed with a small amount of 1980 St. Helens volcanic ash. (1 to 2 inches thick)
A--1 to 5 inches; brown (10YR 5/3) ashy sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to weak fine and medium granular; soft, very friable, nonsticky and nonplastic; many very fine and fine, common medium, and few coarse roots; many very fine irregular pores; 30 percent pumice less than 2 mm in size; 5 percent gravel; NaF pH 11.5; slightly acid (pH 6.2); clear smooth boundary. (3 to 7 inches thick)
Bw1--5 to 15 inches; pale brown (10YR 6/3) gravelly ashy sandy loam, dark brown (10YR 3/3) moist; soft, very friable, nonsticky and nonplastic; moderate fine and medium subangular blocky structure parting to moderate fine granular; many very fine and fine, common medium, and few coarse roots; many very fine irregular pores; 25 percent pumice less than 2 mm in size; 15 percent gravel and 5 percent cobbles; NaF pH 11.0; slightly acid (pH 6.4); gradual smooth boundary.
Bw2--15 to 21 inches; light yellowish brown (10YR 6/4) very gravelly ashy sandy loam, dark yellowish brown (10YR 3/4) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and few medium roots; many very fine irregular pores; 15 percent pumice; 25 percent gravel (2 to 10 mm in size) and 10 percent cobbles; NaF pH 11.0; neutral (pH 6.6); gradual smooth boundary.
Bw3--21 to 29 inches; light yellowish brown (10YR 6/4) very gravelly ashy sandy loam, yellowish brown (10YR 5/4) moist; moderate fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, few fine, and few medium roots; common very fine and few fine tubular pores; 45 percent gravel (2 to 10 mm) and 5 percent cobbles; NaF pH 10.1; neutral (pH 6.6); gradual smooth boundary. (Combined thickness of the Bw horizons is 10 to 25 inches)
2Bt1--29 to 41 inches; light yellowish brown (10YR 6/4) very gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; moderate medium and coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine, fine, and medium roots; common fine tubular pores; few distinct clay films on faces of peds; 40 percent gravel and 15 percent cobbles; NaF pH 9.2; neutral (pH 6.6); gradual wavy boundary.
2Bt2--41 to 54 inches; brownish yellow (10YR 6/6) extremely gravelly fine sandy loam, dark yellowish brown (10YR 4/6) moist; moderate medium and coarse subangular blocky structure; hard, friable, slightly sticky and slightly sticky; few very fine and fine roots; common fine tubular pores; common distinct clay films on faces of peds; 35 percent gravel, 25 percent cobbles and 1 percent stones; slightly acid (pH 6.4); gradual smooth boundary.
2Bt3--54 to 67 inches; brownish yellow (10YR 6/6) very gravelly fine sandy loam, dark yellowish brown (10YR 4/6) moist; moderate medium and coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few fine tubular pores; common distinct clay films on faces of peds; 30 percent gravel and 10 percent cobbles; neutral (pH 6.8). (Combined thickness of 2Bt horizons is 25 to 48 inches)
TYPE LOCATION: Yakima County, Washington; about 1 mile north of Rimrock Lake, Yakima County, Washington, about 550 feet south and 150 feet east of the northwest corner of section 35, T. 14 N, R. 13 E.; Latitude 46 degrees 39 minutes 48 seconds N. and Longitude 121 degrees 10 minutes 33 seconds W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at 20 inches is 42 to 44 degrees. The estimated mean annual summer soil temperature is 43 to 47 degrees F. These soils are usually moist but are dry in all parts of the moisture control section for 45 to 60 consecutive days following the summer solstice. The depth of andic soil material is 14 to 30 inches and has estimated moist bulk density of 0.75 to 1.10 g/cm3, glass content of 30 to 80 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 1 to 2 percent, a phosphate retention of 40 to 55 percent and 15-bar water retention of 8 to 12 percent for air dried samples. The lower part of the particle-size control section contains 40 to 65 percent rock fragments and 18 to 35 percent clay.
The A horizon has hue of 10YR or 7.5YR value of 4 to 6 dry and 3 or 4 moist.
The Bw horizon has hue of 10YR or 7.5YR and chroma of 3 or 4 dry and moist. Texture is gravelly ashy sandy loam, very gravelly ashy sandy loam or extremely gravelly ashy sandy loam. Reaction is slightly acid or neutral.
The 2Bt horizons have hue of 10YR or 7.5YR, value of 4 or 5 moist and chroma of 4 through 6 dry and moist. The fine-earth texture is fine sandy loam, loam or sandy clay loam. Rock fragments range from 35 to 65 percent. Reaction is slightly acid or neutral.
COMPETING SERIES: These are the Burpeak and Chewack series. Burpeak soils are 40 to 60 inches to fractured andesite bedrock, lack an argillic horizon, and the lower part of the particle-size control section has 5 to 12 percent clay. Chewack soils dont have an argillic horizon and the andic soil material has bulk density of 1.10 to 1.30 g/cm3.
GEOGRAPHIC SETTING: Fiscus soils are on ridges and mountain side slopes. Slopes are 10 to 70 percent. They formed in volcanic ash over colluvium from basalt and andesite. Elevations are 3,000 to 6,200 feet. Climate is characterized by warm, dry summers and cool, moist winters. The mean annual precipitation is 40 to 70 inches. The average January temperature is 24 degrees F. and the average July temperature is 62 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 Fifesridge, Terence and Pileup soils. Fifesridge soils are on mountain slopes and are fine-loamy. Terence soils are on mountain slopes and are ashy-skeletal. Pileup soils are on mountain slopes and are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid over moderately slow permeability.
USE AND VEGETATION: These soils are used mainly for timber production, recreation and wildlife habitat. Native vegetation is lodgepole pine, subalpine fir, Engelmann spruce, western larch, Douglas-fir, grand fir and western white pine, with an understory of pinegrass, long tube twinflower, pachistima, western princess pine, elk sedge, Jacobs-ladder, and big huckleberry.
DISTRIBUTION AND EXTENT: Eastern slopes of the Cascade Mountains in central and south central Washington. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wenatchee National Forest, Yakima County, Washington, 2003.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon - 1 to 5 inches (A horizon)
Andic Soil Properties - 1 to 29 inches (A, Bw1, Bw2 and Bw3 horizons)
Argillic horizon - 29 to 67 inches (2Bt1, 2Bt2 and 2Bt3 horizons)
Particle-size Control Section - 1 to 41 inches (A, Bw1, Bw2, Bw3 and 2Bt1 horizons) with 1 to 15 inches qualifying as ashy, 15 to 29 inches as ashy-skeletal and 29 to 41 inches as loamy-skeletal.
Alfic subgroup feature - argillic horizon beginning at a depth of 29 inches.
Classification changed 1/2000 from mixed mineralogy to glassy over isotic.
Depth to diagnostic horizons and features are measured from the top of the first mineral horizon.
More investigation is needed as to this series having a udic soil moisture regime based on presence of Engelmann spruce, subalpine fir and twinflower. If udic, this series would be similar to the Twolakes series.
ADDITIONAL DATA: Laboratory data is available for this soil. Yakima Indian Nation soils laboratory sample number 55B-8-2 and NSSL, Lincoln, NE. sample number S91WA-077-003.