LOCATION STUDEBAKER WAEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed Typic Cryorthents
TYPICAL PEDON: Studebaker very gravelly loamy sand on a 15 percent southwest-facing slope at an elevation of 3,500 feet. (Colors are for moist soils unless otherwise stated)
C1--0 to 6 inches; dark gray (10YR 4/1) very gravelly loamy sand, light gray (10YR 6/1) dry; single grain, loose, nonsticky and nonplastic; many medium and coarse irregular pores; 15 percent cobbles and 40 percent pebbles; 15 percent pumice fragments; moderately acid (pH 6.0); clear wavy boundary. (5 to 8 inches thick)
C2--6 to 60 inches; dark gray (10YR 4/1) extremely gravelly loamy sand, gray (10YR 5/1) dry; single grain, loose, nonsticky and nonplastic; many medium and coarse irregular pores; 20 percent cobbles, 45 percent pebbles, and 15 percent pumice fragments; moderately acid (pH 5.8).
TYPE LOCATION: Skamania County, Washington, about 3.5 miles west of Spirit Lake, 2,000 feet south and 1,500 feet east of the northwest corner of sec. 19, T. 9 N., R. 5 E.
RANGE IN CHARACTERISTICS: The average annual soil temperature ranges from 38 to 43 degrees F. The particle-size control section averages 35 to 80 percent coarse fragments and 15 to 50 percent volcanic glass and glass aggregates. It is very strongly acid to moderately acid.
The C1 horizon has hue of 2.5YR to 10YR, value of 3 to 6 moist, 4 to 8 dry, and chroma of 1 to 4 moist or dry. Texture of the surface layer is variable and ranges from loamy sand to extremely cindery sand.
The C2 horizon has hue of 2.5YR to 10YR, value of 3 to 5 moist, 4 to 8 dry, and chroma of 1 to 3 moist. It is very gravelly loamy sand, extremely gravelly loamy sand, or extremely cobbly sand. Fine stratification with varying amounts of gravel is common.
COMPETING SERIES: These are the Alflack, Canladore, Castlepeak, Chena, Cryomont, Graylock, Howardsville, Legault, Mirror Lake, Nataga, Nizina, Obscurity, Pirapeak, Ragamuffin and Stecum series. Alflack and Ragamuffin soils are moderately deep to bedrock. Castlepeak soils lack volcanic glass and glass aggregates in the profile and have Bw horizons. Chena, Graylock, Mirror Lake, Nizina, Ovando, and Stecum soils lack volcanic ash in the particle-size control section. In addition, Chena soils have a mean annual soil temperature of about 30 degrees F. Cryomont soils have A and Bw horizons and have solum thickness of 10 to 18 inches. Graylock soils have a chroma of 3 or 4 in the control section, lack basalt fragments, and have granitic rock fragments in the control section. Howardsville, Nataga, and Pirapeak soils lack volcanic glass and glass aggregates in the soil profile. Nataga soils also receive 35 to 60 inches of annual precipitation. Legault soils are shallow to bedrock. Mirror Lake soils have 35 to 70 percent quartzite and sandstone fragments in the control section, and have a hue of 7.5YR or 5YR in the C horizon. Stecum soils have a lithic contact within 40 inches of the surface. Canladore soils have an albic horizon. Polepatch soils have an A horizon. Obscurity soils are stratified in the particle-size control section.
GEOGRAPHIC SETTING: The Studebaker soils are on highly irregular, dissected fill in the Toutle River Valley at elevations of 2,700 to 5,500 feet. Studebaker soils formed in avalanche debris material from the May 18, 1980 eruption of Mt. St. Helens. These deposits are 20 to 200 feet in depth. The climate is characterized by warm, moist summers and cold, wet winters. Average annual precipitation is 125 to 140 inches including considerable snowfall. Average January temperature is 25 degrees F; average July temperature is 59 degrees F; and average annual temperature is 40 to 45 degrees F. The growing season is 70 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Obscurity soils and the Panhandle and Wakepish soils. Panhandle soils are cindery. Wakepish soils are frigid.
DRAINAGE AND PERMEABILITY : Somewhat excessively drained; slow runoff; moderately rapid permeability.
USE AND VEGETATION: Used as a National Geologic Monument. Areas have been revegetated with grass seedings and willow cuttings. Natural revegetation by fireweed, pearly everlasting, and red alder has begun.
DISTRIBUTION AND EXTENT: Northern Skamania and eastern Cowlitz Counties, Washington. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Skamania County, Washington, 1984.
REMARKS: This pedon has partial lab data S81WA-059-6 and 7. This pedon has no diagnostic horizons. The particle-size control section (10 to 40 inches) in 65 percent pebbles and 15 percent pumice and loamy sand in the fine earth fraction.