LOCATION BEAR PRAIRIE WAEstablished Series
TAXONOMIC CLASS: Medial, ferrihydritic, mesic Pachic Melanudands
TYPICAL PEDON: Bear Prairie medial silt loam - fern and scattered trees. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 2 inches; slightly decomposed litter of needles, leaves and twigs.
Oe--2 to 3 inches; black (10YR 2/1) moderately decomposed organic material; weak fine granular structure; very friable; few fine roots; abrupt smooth boundary. (1/2 to l inch thick)
Al--3 to 10 inches; black (10YR 2/1) medial silt loam, very dark grayish brown (10YR 3/2) dry; moderate very fine granular structure; slightly hard, very friable, nonsticky, nonplastic and weakly smeary; many fine, medium, and coarse roots; very strongly acid (pH 5.0); abrupt smooth boundary. (6 to l0 inches thick)
A2--10 to 18 inches; very dark brown (10YR 2/2) medial silt loam, very dark grayish brown (10YR 3/2) dry; moderate very fine granular structure; slightly hard, very friable, nonsticky, nonplastic and weakly smeary; many fine, medium and coarse roots; strongly acid (pH 5.2); clear wavy boundary. (6 to l0 inches thick)
AB--18 to 28 inches; dark brown (10YR 3/3) medial silt loam, brown (10YR 4/3) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic and weakly smeary; many fine, medium and coarse roots; many fine and medium pores; strongly acid (pH 5.5); clear irregular boundary. (5 to 20 inches thick)
Bwl--28 to 45 inches; dark yellowish brown (10YR 4/4) medial silt loam, yellowish brown (10YR 5/4) dry; weak fine subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic and weakly smeary; common fine and medium roots; common fine and few medium pores; strongly acid (pH 5.5); gradual wavy boundary. (15 to 20 inches thick)
Bw2--45 to 54 inches; dark yellowish brown (10YR 4/4) medial silt loam, yellowish brown (10YR 5/4) dry; weak fine subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic and weakly smeary; common fine roots; many fine tubular pores; few very thin coatings on surfaces of peds; about 10 percent angular cobbles; common fine pumice grains; strongly acid (pH 5.5); clear smooth boundary. (8 to 11 inches thick)
2C--54 to 78 inches; dusky red (2.5YR 3/2) loam, dark reddish gray (5YR 4/2) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine roots; few fine tubular pores; moderately acid (pH 5.7).
TYPE LOCATION: Clark County, Washington; located about 200 feet northwest of a northeasterly highway curve, l00 feet south and l,700 feet west of northwest corner section 24, T. 2 N., R. 4 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 52 F. The solum has a moist bulk density of 0.60 to 0.90 g/cc, acid oxalate extractable aluminum plus one-half the acid oxalate iron of 2.0 to 3.0, phosphate retention of 85 to 95 percent. The melanic epipedon is 12 to 20 inches thick. The umbric epipedon is 20 to 30 inches thick. The A horizon has value of 2 moist, 3 or 4 dry, and chroma of 1 or 2 moist or dry. It has weak or moderate granular and blocky structure. It is very strongly acid or extremely acid. It has 10 to 15 percent organic matter.
The Bw horizon has value of 3 or 4 moist, and chroma of 3 or 4 moist or dry. It is medial silt loam, medial silty clay loam, or medial clay loam. It is moderately acid to very strongly acid.
The 2C horizon, where present, ranges from dusky red to yellowish brown. It has redox features below depths of 40 inches in some pedons. It is loam or stratified fine sand to sandy clay loam or silty clay. It is massive, single grained, or has weak subangular blocky structure.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Bear Prairie soils are on high terraces and terrace escarpments at elevation of 20 to l800 feet. These soils formed in old alluvium. Slopes are 0 to 50 percent. Bear Prairie soils are in a humid climate with relatively cool dry summers and mild wet winters. They have a mean precipitation of 65 to l20 inches; mean January temperature of 35 F.; mean July temperature of 62 F.; a mean annual temperature of 50 F., and a growing season (28 F) of 200 to 240 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arta, Astoria, Buckpeak, Elochoman, Hebo, Kinney, Olympic, and Zenker soils. Arta, Astoria, Buckpeak, Elochoman, Kenney and Zenker soils have an umbric epipedon less than 20 inches thick. Hebo soils have an aquic moisture regime. Olympic soils have an argillic horizon. Olympic and Buckpeak soils have a xeric moisture regime.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability.
USE AND VEGETATION: Mostly hay and pasture. Native vegetation is western Hemlock, Douglas-fir, western redcedar, Sitka spruce and red alder with an understory of western brackenfern, salal, trailing blackberry, salmonberry, western swordfern, Oregon oxalis, vine maple and red huckleberry.
DISTRIBUTION AND EXTENT: Western Washington; MLRA 1 and 3. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Skamania County, Washington, l947.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
umbric epipedon - from 3 to 28 inches
melanic epipedon - from 3 to 18 inches
cambic horizon - from 28 to 54 inches
The areas mapped in Grays Harbor County, Washington are in the isomesic soil temperature regime area and need re-correlation.