LOCATION VADER WAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, isotic, mesic Vitrandic Dystroxerepts
TYPICAL PEDON: Vader loam - under a coniferous forest on a 38 percent convex south-facing back slope at an elevation of 680 feet. (The soil was moist when described. Colors are for dry soil unless otherwise stated. All textures are apparent field textures.)
Oe--0 to 1 inch; loose, partially decomposed organic litter, including needles, leaves, twigs, bark chips, and cones; abrupt smooth boundary. (1 to 4 inches thick)
A--1 to 5 inches; very dark brown (10YR 2/2) loam, grayish brown (10YR 5/2) dry; weak fine subangular blocky structure parting to weak fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine and fine, and common medium roots; many very fine irregular pores; 30 percent soft sandstone pebbles and rounded, shot-like aggregates (2-10 mm in diameter); moderately acid (pH 5.8); clear wavy boundary. (3 to 7 inches thick)
BA--5 to 15 inches; dark brown (10YR 3/3) loam, pale brown (10YR 6/3) dry; weak medium subangular blocky structure parting to weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine, common medium and coarse roots; many very fine tubular pores; 20 percent soft sandstone pebbles and rounded, shot-like aggregates (2-10 mm in diameter); moderately acid (pH 5.6); clear wavy boundary. (0 to 12 inches thick)
Bw1--15 to 24 inches; dark brown (10YR 4/3) loam, pale brown (10YR 6/3) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine, medium, and coarse roots; many fine tubular pores; 5 percent soft sandstone pebbles and rounded, shot-like aggregates (2-10 mm in diameter); moderately acid (pH 5.6); clear wavy boundary.
Bw2--24 to 31 inches; dark yellowish brown (10YR 4/4) sandy loam, light yellowish brown (10YR 6/4) dry; weak coarse subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; few fine, medium, and coarse roots; few pores; strongly acid (pH 5.4); clear wavy boundary. (Combined thickness of the Bw horizon is 11 to 22 inches)
BC--31 to 51 inches; yellowish brown (10YR 5/4) loamy sand, very pale brown (10YR 7/4) dry; massive; slightly hard, very friable, nonsticky and nonplastic; few fine and medium roots; few pores; 10 percent soft sandstone pebbles; strongly acid (pH 5.2); clear wavy boundary. (14 to 24 inches thick)
C--51 to 61 inches; light olive brown (2.5Y 5/4) loamy sand, pale yellow (2.5Y 7/4) dry, about 10 percent is strong brown (7.5YR 5/6), reddish yellow (7.5YR 7/6) dry; massive; slightly hard, very friable, nonsticky and nonplastic; few fine roots; 20 percent soft sandstone pebbles; strongly acid (pH 5.2).
TYPE LOCATION: Lewis County, Washington; 2 miles west of Doty, 150 feet north upslope from Weyerhaeuser logging road no. 7010 near the intersection with no. 7013; 2,150 feet south and 650 feet east of the northwest corner section 4, T. 13 N., R. 5 W., W.M.
RANGE IN CHARACTERISTICS: These soils are usually moist, but are dry in the moisture control section for 45 to 60 consecutive days following the summer solstice. Average annual soil temperature at a depth of 20 inches ranges from 49 to 53 degrees F. Depth to a paralithic contact with weathered sandstone that slakes in water is more than 40 inches. The particle-size control section contains 0 to 30 percent pebble and cobble-size soft sandstone fragments and averages 30 to 60 percent sand coarser than very fine sand. The soil is moderately acid to very strongly acid throughout.
The A horizon has hue of 5YR through 10YR, value of 2 to 4 moist, 4 or 5 dry, and chroma of 2 to 4 moist and dry. Soft sandstone pebbles and shot-like aggregates range from 0 to 30 percent.
The Bw horizon has hue of 5YR, 7.5YR or 10YR, value of 3 or 4 moist, 5 to 7 dry, and chroma of 3 to 6 moist and dry. It is loam, fine sandy loam, or sandy loam. Rounded and subangular soft sandstone pebbles range from 0 to 30 percent.
The BC horizon has hue of 10YR or 7.5YR, value of 4 or 5 moist, 6 to 8 dry and chroma of 3 to 8 moist and dry. It is fine sandy loam, sandy loam, or loamy sand. Soft sandstone fragments range from 0 to 30 percent.
The C horizon has hue of 7.5YR through 2.5YR, value of 4 or 5 moist, 5 to 7 dry, and chroma of 4 to 8 moist and dry. It is fine sandy loam, sandy loam, loamy fine sand, or loamy sand. Soft sandstone pebbles and cobbles range from 0 to 50 percent.
COMPETING SERIES: These are the Chaix, Dome, Elwha, Gilligan, Loper, Siskiyou, Tethrick, and Ulricher series. Chaix, Elwha, Loper, and Siskiyou soils have a paralithic contact at a depth of 20 to 40 inches. Dome soils are dry more than 60 consecutive days. Fidalgo soils are moderately deep to serpentine. Gilligan soils average 15 to 30 percent sand coarser than very fine sand in the particle-size control section and are silt loam or very fine sand in the upper part of the particle-size control section. Tethrick soils are slightly acid and are dry for 60 to 80 consecutive days. Ulricher soils are dry for 90 to 120 days and have up to 35 percent unweathered rock fragments in the particle-size control section.
GEOGRAPHIC SETTING: Vader soils are on uplands and foothills at elevations of 50 to 1,800 feet. Slopes are 5 to 65 percent. These soils formed in residuum and colluvium weathered from thickly-bedded, quartzitic, micaceous fine sandstone with an admixture of volcanic ash in the upper part. The climate is marine and characterized by cool, dry summers and mild, wet winters. Average annual precipitation is 50 to 70 inches. Average annual temperature is 47 to 51 degrees F. Growing season (28 degrees F) is 150 to 225 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Buckpeak, Centralia, Galvin, Melbourne, Olequa, Prather, and Reed soils. Buckpeak and Centralia soils are fine-loamy. Galvin and Olequa soils are fine-silty and have an argillic horizon. Melbourne and Prather soils are fine and have an argillic horizon. Reed soils are fine, have a mollic epipedon and an aquic moisture regime.
DRAINAGE AND PERMEABILITY: Well-drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: Used for timber production, wildlife habitat, and watershed. Overstory vegetation is Douglas-fir, western hemlock, and red alder. Understory and ground vegetation is tree seedlings, vine maple, salal, Oregon-grape, rose, western brackenfern, western swordfern, trailing blackberry, vanilla leaf, Hooker fairybells, rattlesnake plantain, wild ginger, and redwood violet.
DISTRIBUTION AND EXTENT: Uplands and foothills of western Lewis and western Cowlitz Counties, Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lewis County, Washington, 1941.
REMARKS: Classification only updated 3/94 because of recent amendments to Soil Taxonomy. Diagnostic horizons and features recognized in this pedon are an ochric epipedon from 1 to 15 inches and a cambic horizon from 15 to 31 inches.
Classification updated 1/00 from Vitrandic Xerochrepts to Vitrandic Dystroxerepts based on amendments to Soil Taxonomy.
This series needs further investigation as to a udic soil moisture regime and isotic mineralogy class.
Depths to diagnostic horizons and features are measured from the top of the first mineral horizon.