LOCATION REED WAEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Vertic Argiaquolls
TYPICAL PEDON: Reed silty clay loam, grass pasture. (Colors are for moist soil unless otherwise stated. Profile was moist to 58 inches when described.)
Ap--0 to 6 inches; very dark grayish brown (10YR 3/2) silty clay loam, grayish brown (10YR 5/2) dry, brown (10YR 5/3) dry, rubbed; many fine prominent yellowish red (5YR 4/6) mottles, strong brown (7.5YR 5/6) dry; weak fine and medium granular structure; hard, friable, slightly sticky, slightly plastic; many very fine and fine roots; many very fine interstitial pores; medium acid (pH 5.6); clear smooth boundary. (3 to 7 inches thick)
A3--6 to 14 inches; very dark grayish brown (10YR 3/2) silty clay loam rubbed, yellowish brown (10YR 5/4) dry, rubbed; many fine prominent reddish brown (5YR 4/3) mottles, strong brown (7.5YR 5/6) dry; brown (10YR 5/3) dry broken; weak medium subangular blocky structure that parts to moderate very fine subangular blocky; hard, friable, slightly sticky, slightly plastic; many very fine and fine roots; many very fine interstitial pores; medium acid (pH 5.6); clear smooth boundary. (4 to 13 inches)
B21tg--14 to 20 inches; brown (10YR 5/3) silty clay, light brownish gray (2.5Y 6/2) dry; pale brown (10YR 6/3) dry, rubbed; many fine prominent reddish brown (5YR 4/4) mottles, yellowish red (5YR 5/8) dry; moderate fine and medium subangular blocky structure; very hard, friable, sticky, plastic; many very fine and fine roots; common very fine tubular pores; few thin clay films on faces of peds and in pores; very strongly acid (pH 5.0); abrupt smooth boundary. (4 to 12 inches thick)
B22tg--20 to 25 inches; very dark gray (10YR 3/1) rubbed clay, grayish brown (10YR 5/2) dry; black (10YR 2/1) faces on peds, dark gray (10YR 4/1) dry; many medium prominent reddish brown (5YR 5/4) mottles; strong brown (7.5YR 5/8) dry; moderate fine and medium subangular blocky structure; hard, friable, sticky, plastic; common very fine roots; common very fine tubular pores; many thin and moderately thick clay films on faces of peds and in pores; very strongly acid (pH 5.0); abrupt smooth boundary. (5 to 15 inches thick)
B23tg--25 to 31 inches; dark gray (10YR 4/1) rubbed clay, grayish brown (10YR 5/2) dry; black (10YR 2/1) faces of peds, gray (10YR 5/1) dry; many medium prominent reddish brown (5YR 4/4) and dark gray (n 4/) mottles, strong brown (7.5YR 5/8) dry; moderate fine and medium subangular blocky structure; very hard, firm, sticky, plastic; few very fine roots; common very fine and fine tubular pores; many thin and moderately thick clay films on faces of peds and in pores; strongly acid (pH 5.4); abrupt smooth boundary. (4 to 10 inches thick)
B24tg--31 to 37 inches; dark grayish brown (10YR 4/2) rubbed silty clay loam, yellowish brown (10YR 5/4) dry; dark gray (N 4/) faces of peds, gray (10YR 6/1) dry, many medium prominent strong brown (7.5YR 5/6) mottles, strong brown (7.5YR 5/8) dry; moderate medium prismatic that parts to weak medium and coarse angular blocky structure; extremely hard, firm, sticky, plastic; few very fine roots; common very fine and fine tubular pores; many thin and moderately thick clay films on faces of peds and in pores; strongly acid (pH 5.4); abrupt smooth boundary. (4 to 10 inches thick)
B25tg--37 to 60 inches; black (10YR 2/1) rubbed clay, dark grayish brown (2.5Y 4/2) dry; very dark gray (n 3/) faces of peds, dark gray (N 4/) dry; many common prominent reddish brown (5YR 4/4) mottles, strong brown (7.5YR 5/8) dry; moderate medium and coarse subangular and angular blocky structure; extremely hard, firm, sticky, plastic; few very fine roots; few very fine and fine tubular pores; continuous thin and moderately thick clay films on faces of peds and in pores; very strongly acid (pH 4.6).
TYPE LOCATION: Lewis County, Washington; about 2 miles north of Chehalis, Washington; 1,500 feet north, 500 feet east of southwest corner section 18, T.14N., R.2W.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 40 to 70 inches. The mean annual soil temperature ranges from 47 to 51 degrees F. Reed soils are usually moist. Soil reaction ranges from medium to very strongly acid. The argillic horizon averages silty clay or clay and has 50 to 70 percent clay.
The A horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist, 2 through 4 dry, and has prominent and distinct mottles. It is silt loam, silty clay loam or silty clay.
The B horizon has hue of 10YR to neutral, value of 3 through 5 moist, 4 through 6 dry, and chroma of 0 through 3 moist or dry. It has moderate to strong subangular blocky to strong prismatic structure. This horizon is silty clay or clay.
COMPETING SERIES: This is the Courtney series. Courtney soils have montmorillonitic mineralogy and do not crack in most years.
GEOGRAPHIC SETTING: Reed soils occur in depressions on low terraces in narrow to wide river valleys adjacent to perennial streams at elevations ranging from 25 to 500 feet. Reed soils formed in mixed alluvium eroded from shale, sandstone, basic igneous rocks, and glacial drift. They are in a marine climate with an annual precipitation of 40 to 80 inches. The mean January temperature is 38 degrees F.; the mean July temperature is 65 degrees F.; and the mean annual temperature of 52 degrees F. The frost free season is 150 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chehalis, Clato, Galvin, and Newruss soils. Chehalis soils are well drained. Clato and Newruss soils lack an argillic horizon. Galvin soils lack an argillic horizon and are somewhat poorly drained.
DRAINAGE AND PERMEABILITY: Poorly drained; very slow runoff; moderate permeability in the A horizons, moderately slow in the B21tg and B22tg horizons and slow below. Reed soils are flooded for short periods when streams overflow and during the winter and early spring have a ground water table within 6 inches of the surface.
USE AND VEGETATION: Where cleared and drained, Reed soils are used for grass hay and pasture, small grains, peas, and corn. Native vegetation is alder, cottonwood, western hemlock, western red cedar, with an understory of marsh grasses, forbes, and shrubs.
DISTRIBUTION AND EXTENT: Western Washington. Series is of modeate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lewis County, Washington, 1976.
REMARKS: This represents a new type location and new concept for the Reed series.
ADDITIONAL DATA: Characterization soil sample number S72WA-21-10.