LOCATION DELAMETER WAEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed, frigid Vitrandic Udorthents
TYPICAL PEDON: Delameter extremely gravelly loamy sand on a 10 percent southwest-facing slope at an elevation of 1,300 feet. (Colors are for moist soils unless otherwise stated.)
C1--0 to 10 inches; dark gray (l0YR 4/1) extremely gravelly loamy sand, light gray (l0YR 6/1) dry; single grain; loose, nonsticky and nonplastic; many medium and coarse pores; 15 percent cobbles and 40 percent pebbles, 15 percent pumice fragments; moderately acid (pH 6.0); clear wavy boundary. (8 to 12 inches thick)
C2--10 to 60 inches; dark gray (l0YR 4/1) extremely gravelly loamy sand, gray (l0YR 5/1) dry; single grain, loose, nonsticky and nonplastic, many medium and coarse irregular pores; 15 percent cobbles, 45 percent pebbles and 15 percent pumice fragments; moderately acid (pH 5.8).
TYPE LOCATION: Cowlitz County Washington. About 14 miles east of Toutle, 560 feet west, 1,750 feet south of the northeast corner section 33, T. 10N., R.3E.
RANGE IN CHARACTERISTICS: The average annual soil temperature ranges from 43 to 47 degrees F. The particle-size control section averages 15 to 30 percent volcanic glass and glass aggregates in the fine earth fraction and is 5 to 25 percent pumice and 35 to 70 percent rock fragments. The upper 7 to 14 inches of this soil is assumed to be 30 to 60 percent volcanic ash and pumice. The soil is moderately acid or slightly acid throughout. Some profiles contain woody organic debris, composed of logs, branches, and bark.
The C1 horizon has hue of 5YR to 2.5Y, value of 3 to 6 moist, 4 to 8 dry and chroma of 1 to 4 moist and dry. Some areas have a stony or bouldery surface. Some areas have a surface layer dominated by cinders.
The C2 horizon has hue of 7.5YR to 2.5Y, value of 3 to 5 moist, 4 to 8 dry, and chroma of 1 to 3 moist and dry. It is very gravelly loamy sand, extremely gravelly loamy sand or extremely cobbly sand.
COMPETING SERIES: This is the Wakepish series. Wakepish soils are sandy loam in the upper part of the particle-size control section, are subject to frequent, brief flooding and formed in mudflow material.
GEOGRAPHIC SETTING: The Delameter soils are on highly irregular, dissected valley floors and formed in avalanche debris flow from the May 18 eruption of Mt. St. Helens These soils are in the Toutle River Valley at elevations of 1,200 to 2,700 feet. Slopes are mostly 0 to 20 percent, but some short slopes range to 100 percent. The avalanche debris deposits are 20 to 200 feet in depth. The climate is characterized by warm, moist summers and cold, wet winters. Average annual precipitation is 90 to 110 inches including snowfall. Average January temperature is 28 degrees F., average July temperature is 6l degrees F.; and the average annual temperature is 40 to 45 degrees F. The growing season is 125 to 175 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the similar Studebaker soils. Studebaker soils are at elevations above 2,700 feet and have a cryic temperature regime.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; slow runoff; rapid permeability.
USE AND VEGETATION: Some areas are included in the National Geologic Monument. Other areas have been revegetated with grass and legume seedings and willow cuttings. Natural revegetation by fireweed, pearly everlasting and red alder has begun.
DISTRIBUTION AND EXTENT: Eastern Cowlitz County, Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Cowlitz County, Washington 1989.
REMARKS: Diagnostic horizons and features recognized in this pedon are a particle-size control section from l0 to 40 inches that is sandy throughout and averages 75 percent rock and pumice fragments. Vitrandic feature - from 7 to 14 inches having 30 to 60 percent glass.
Classification change 7/98 based on 1998 Keys to Taxonomy.