LOCATION KINTON OREstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Typic Fragixerepts
TYPICAL PEDON: Kinton silt loam, woodland. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inch; duff, needles, twigs, leaves.
A1--1 to 4 inches; very dark brown (10YR 2/2) silt loam, grayish brown (10YR 5/2) dry; strong fine granular structure; friable, slightly sticky and slightly plastic; many fine roots; many very fine irregular pores; 5 percent fine concretions; moderately acid (pH 5.9); abrupt smooth boundary. (3 to 8 inches thick)
A2--4 to 11 inches; dark yellowish brown (10YR 3/4) silt loam, pale brown (10YR 6/3) dry; moderate fine subangular blocky structure; friable, slightly sticky and slightly plastic; few fine and medium roots; many very fine tubular pores; 2 percent fine concretions; moderately acid (pH 5.9); clear smooth boundary. (0 to 8 inches thick)
BA--11 to 17 inches; brown (10YR 4/3) silt loam, pale brown (10YR 6/3) dry; moderate fine subangular blocky structure; friable, slightly sticky and slightly plastic; common very fine few medium and coarse roots; many very fine tubular pores; common fine concretions; moderately acid (pH 5.6); clear wavy boundary. (0 to 7 inches thick)
Bw1--17 to 22 inches; brown (10YR 4/3) silt loam, pale brown (10YR 6/3) dry; moderate fine subangular blocky structure; firm, slightly sticky and slightly plastic; common very fine, few medium and coarse roots; many very fine tubular pores; trace of concretions; strongly acid (pH 5.5); clear wavy boundary. (4 to 7 inches thick)
Bw2--22 to 31 inches; brown (10YR 4/3) silt loam, pale brown (10YR 6/3) dry; moderate fine subangular blocky structure; firm, moderately sticky and moderately plastic; few fine roots; many very fine tubular pores; strongly acid (pH 5.3); clear wavy boundary. (7 to 11 inches thick)
2Btx1--31 to 40 inches; brown (10YR 4/3) silt loam, light yellowish brown (10YR 6/4) dry; few fine distinct yellowish brown (10YR 5/6) mottles; weak coarse subangular blocky structure; firm, brittle, moderately sticky and moderately plastic; few fine roots; many very fine tubular pores; few faint clay films; few fine coatings of grayish brown (10YR 5/2) on faces of some peds; strongly acid (pH 5.3); clear wavy boundary. (6 to 9 inches thick)
2Btx2--40 to 50 inches; brown (10YR 4/3) silt loam, light yellowish brown (10YR 6/4) dry; grayish brown (10YR 5/2) tongues about 1 foot apart; strong brown (7.5YR 5/6) redox concentrations and margins along tongues; moderate very coarse prismatic parting to weak coarse blocky structure; very firm, brittle, moderately sticky and moderately plastic; trace of roots; many very fine tubular pores; common distinct thick clay films on faces of prisms; many fine black stains; strongly acid (pH 5.3); gradual wavy boundary. (7 to 12 inches thick)
2Btx3--50 to 61 inches; brown (10YR 4/3) silt loam, light yellowish brown (10YR 6/4) dry; grayish brown (10YR 5/2) tongues in vertical cracks about 1 foot apart; few yellowish brown (10YR 5/6) redox concentrations and tongue margins; massive with vertical cracking 1 foot apart; very firm, brittle, slightly sticky and slightly plastic; few fine tubular pores; few distinct clay films on faces of cracks; moderately acid (pH 5.6).
TYPE LOCATION: Washington County, Oregon; about 1.5 miles west of Sherwood, Oregon; 0.4 mile west of Elwert and Haide Road junction; SW1/4 NW1/4 NE1/4 section 36, T.2S., R.2W.
RANGE IN CHARACTERISTICS: The soils are usually moist but are dry throughout between depths of 4 and 12 inches for more than 45 consecutive days during the summer. The mean annual soil temperature ranges from 52 to 56 degrees F. The depth to the fragipan ranges from 30 to 40 inches. Depth to bedrock is 60 inches or more.
The A horizon to depths 3 to 8 inches has value of 2 or 3 moist, 4 or 5 dry and chroma of 2 or 3 moist and 2 dry. Below 3 to 8 inches the A horizon has value of 3 or 4 and 6 dry, and chroma of 3 or 4 moist and dry.
The Bw horizon has chroma of 3 or 4 moist and dry. The field texture is silt loam with 18 to 27 percent clay and less than 15 percent coarser than very fine sand. Measured clay is less than 15 percent as a weighed average but the 15 bar water (percentage) ranges from about 8 to 10 and the ratio of measured clay to 15 bar water is about 1 to 1.6 in the B horizon. A few faint redox concentrations with chroma of 3 or 4 in hue of 5 YR or 7.5YR are near the boundary with the fragipan in some pedons.
The 2Btx horizon has matrix colors similar to the horizons above to it but has faint to prominent redox concentrations with chroma of more than 2 and tongue with chroma of 2. It is firm or very firm and brittle and has few to many faint to distinct clay films on many faces of peds. It is silt loam or silty clay loam and commonly is 2 feet or more thick. A dark reddish brown (2.5YR 3/4) buried clay soil underlies the fragipan in some areas.
COMPETING SERIES: These are the Glohm and Powell series. Glohm soils have a udic moisture regime. Powell soils have mottles with chroma of 2 above depth of 30 inches and have a field texture of coarse, silty.
GEOGRAPHIC SETTING: The Kinton soils are on smooth or rolling low hills with convex, long slopes and ridgetops on all exposures. The soils formed in loess like material over fine, silty old alluvium of mixed origin. The soils are at 250 to 400 feet elevation and formed under cool moist winter and a warm dry summer climate. The average July temperature is 66 degrees F.; the average January temperature is 39 degrees F.; and the average annual temperature is 52 to 54 degrees F. The average annual precipitation is 40 to 50 inches. The frost free period is 165 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Cascade soils and the Cornelius, Delena, Helvetia, Laurelwood and Saum soils. Cornelius soils have argillic horizons above the fragipan. Laurelwood and Helvetia soils have argillic horizons and lack fragipans. Saum soils lack a fragipan.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow to rapid surface runoff; moderately permeability above fragipan and slow in the fragipan.
USE AND VEGETATION: Soils are used for berries, orchards, small grain and seed crops, hay, pasture and woodland. Native vegetation consists of Douglas fir, bigleaf maple, western red cedar, hazelbrush, poison oak and other shrubs and grasses.
DISTRIBUTION AND EXTENT: Northwestern Oregon, Columbia, Multnomah and Washington Counties. The soil is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Washington County, Oregon, 1975.
ADDITIONAL DATA: Characterization data on one profile (S70 OR-34-1) reported in Riverside Soil Survey Laboratory Report for soils sampled in Washington County, Oregon, 1970.