LOCATION TRADEDOLLAR WAEstablished Series
TAXONOMIC CLASS: Pumiceous, glassy Andic Haplocryods
TYPICAL PEDON: Tradedollar sandy loam - under a coniferous forest on a 40 percent convex northwest facing back slope at an elevation of 4,420 feet. (The soil was moist when described. Colors are for moist soil unless otherwise stated. All textures are apparent field textures.)
Oe--3 inches to 0; loose, partially decomposed organic litter, composed of needles, leaves, twigs, cones, bark chips and roots; abrupt wavy boundary. (l to 4 inches thick)
E--0 to l inch: dark gray (l0YR 4/l) sandy loam, gray (l0YR 6/l) dry; massive; slightly hard, very friable, nonsticky, nonplastic and weakly smeary; many very fine, fine, medium and coarse roots; 5 percent pebble-size subangular pumice fragments; moderately acid (pH 5.6); abrupt wavy boundary. (0.5 to 3 inches thick)
Bhs--l to 4 inches: very dark brown (l0YR 2/2) sandy loam, pale brown (l0YR 6/3) dry; moderate fine and medium subangular blocky structure; slightly hard, very friable, nonsticky, nonplastic and weakly smeary; many very fine, fine medium and coarse roots; common fine pores; 5 percent subangular pumice fragments (2 to 50 mm in diameter); moderately acid (pH 5.6); clear wavy boundary. (l to 3 inches thick)
Bs1--4 to 8 inches; dark brown (7.5YR 3/4) paragravelly sandy loam, reddish yellow (7.5YR 6/6) dry; many fine faint yellowish red (5YR 4/6) mottles, strong brown (7.5YR 5/6) dry; weak fine and medium subangular blocky structure; slightly hard, very friable, nonsticky, nonplastic and weakly smeary; many very fine, fine, medium and coarse roots; common fine pores; l5 percent subangular pumice fragments (2 to 50 mm in diameter); strongly acid (pH 5.4); abrupt wavy boundary. (3 to 6 inches thick)
Bs2--8 to l3 inches; strong brown (7.5YR 5/6) very paragravelly sandy loam, reddish yellow (7.5YR 7/6) dry; many fine faint yellowish red (5YR 4/6) mottles, strong brown (7.5YR 5/6) dry; weak fine and medium subangular blocky structure; slightly hard, very friable, nonsticky, nonplastic and weakly smeary; common very fine and fine, many medium and coarse roots; few fine pores; 50 percent subangular pumice fragments (2 to 60 mm in in diameter); moderately acid (pH 6.0); clear wavy boundary. (4 to 8 inches thick)
Bs3--l3 to 22 inches; yellowish red (5YR 4/6) extremely paragravelly sand, yellowish red (5YR 5/6) dry; single grain; loose; few very fine, fine and medium roots; 70 percent subangular pumice fragments (2 to 70 mm in diameter but most are l0-40 mm); moderately acid (pH 6.0); clear wavy boundary. (8 to l2 inches thick)
Bs4--22 to 52 inches; yellowish red (7.5YR 5/8) extremely paragravelly, reddish yellow (7.5YR 7/8) dry; single grain; loose; few very fine, fine and medium roots; 95 percent pebble-size (most are 20-50 mm in diameter); and cobble-size (8 to ll cm in diameter) subangular pumice fragments; moderately acid (pH 6.0); abrupt wavy boundary. (20 to 40 inches thick)
2Eb--52 to 55 inches; dark grayish brown (l0YR 4/2) gravelly sandy loam, gray (l0YR 6/l) dry; massive; hard, friable, slightly sticky, nonplastic and weakly smeary; few roots; few pores; 25 percent subangular unweathered pebbles; moderately acid (pH 5.8); abrupt wavy boundary. (l to 5 inches thick)
2Bwb--55 to 60 inches; dark grayish brown (l0YR 4/2) gravelly sandy loam, gray (l0YR 6/l) dry; massive; hard, friable, slightly sticky, slightly plastic and weakly smeary; few roots; few pores; 50 percent subangular unweathered pebbles; moderately acid (pH 6.0).
TYPE LOCATION: Lewis County, Washington; near the Vanson Lake trail about 750 feet northeast of Vanson Lake; l,880 feet north and 0 feet west of the southeast corner of sec. 27, T. ll N., R. 5 E., W.M.
RANGE IN CHARACTERISTICS: Mean annual soil temperature at a depth of 20 inches is 40 to 42 degrees F. Depth to the buried profile is more than 40 inches. Reaction ranges from strongly acid to moderately acid throughout the profile.
The Al horizon has hue of l0YR or 2.5Y, value of 4 or 5 moist, 6 through 8 dry, and chroma of 0 through 2 moist and dry.
The A2 horizon has hue of l0YR or 7.5YR, value of 2 or 3 moist, 4 through 6 dry, and chroma of 2 or 3 moist and dry.
The Bsl horizon has hue of 7.5YR or 5YR, value of 3 or 4 moist, 5 or 6 dry, and chroma of 4 through 6 moist and dry. It has l5 to 30 percent pebble-size pumice fragments.
The Bs2 horizon has hue of 7.5YR or 5YR, value of 4 through 6 moist, 6 through 8 dry, and chroma of 2 through 6 moist and dry. It has 30 to 55 percent pebble-size pumice fragments and 0 to l5 percent hard pebbles.
The Bs3 and Bs4 horizons have hue of 7.5YR or 5YR, value of 4 through 6 moist, 2 through 8 dry, and chroma of 6 through 8 moist and dry. They contain a total of 60 to 95 percent pumice fragments and 0 to l5 percent hard pebbles. Pebble-size pumice fragments range from 35 to 55 percent and cobble-size fragments average from 25 to 45 percent.
The 2Eb and 2Bwb horizons have unweathered pebbles ranging from l5 to 45 percent and 0 to 20 percent pumice.
COMPETING SERIES: There are no competing series. The Cattcreek, Colter, Cotteral, and Wedge series are similar. Cattcreek soils are cindery over medial-skeletal. Colter soils are cindery over medial and do not have a spodic horizon. Cotteral soils are cindery over medial. Wedge soils have sola l6 to 27 inches thick and are dry in all parts between depth of l2 and 36 inches for 60 to 80 days in the summer.
GEOGRAPHIC SETTING: Tradedollar soils are in upland basins, on mountainsides, and broad ridgetops at elevations of 2,800 to 5,400 feet. Slopes are 0 to 90 percent. These soils formed in a layer of aerially deposited dacitic pumice with a mantle of more recently deposited volcanic ash and pumice. The pumice layer is the Mt. St. Helens "layer Y", deposited about 3,200 years ago. The climate is characterized by cool dry summers and cold wet winters. Average annual precipitation is 70 to 90 inches including considerable snowfall. Mean annual temperature is 38 to 40 degrees F. The growing season (28 degrees F.) is 70 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Cattcreek, Colter, and Cotteral soils, and the Benham, Hatchet and Ohana soils. Benham soils have a frigid temperature regime. Hatchet soils are medial-skeletal and are 20 to 40 inches deep to bedrock. Ohana soils are medial-skeletal and are 20 to 40 inches deep to a paralithic contact.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability in the surface and upper part of the subsoil and moderately rapid below.
USE AND VEGETATION: Used for timber production, wildlife habitat and watershed. Overstory vegetation is tree seedlings, Sitka alder, blue huckleberry, red huckleberry, beargrass and redwood violet.
DISTRIBUTION AND EXTENT: Cascade Range in southeastern Lewis and northern Skamania Counties, Washington, north and northeast of Mt. St. Helens. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lewis County, Washington, l979.
REMARKS: Classification changed 6/98 because of recent amendments to Soil Taxonomy, and in addition minor nomenclature changes and a color change in the upper part of the profile were made.
Diagnostic horizons and features included in this pedon:
Particle-size control section: 10 to 40 inches
Albic horizon: from 0 to 1 inch
Spodic horizon: from 1 to 22 inches (Bhs, Bs1, Bs2, and Bs3 horizons). The Bs4 horizon fails to meet the color requirement for a spodic horizon.