LOCATION SUVER OREstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Aquic Haplohumults
TYPICAL PEDON: Suver silty clay loam, brush and grass. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 6 inches; dark brown (7.5YR 3/2) silty clay loam, brown (7.5YR 5/2) dry; moderate very fine and fine granular and subangular blocky structure; slightly hard, friable, slightly sticky and plastic; many very fine roots; many very fine irregular pores; medium acid (pH 5.6); clear smooth boundary. (4 to 10 inches thick0
A3--6 to 11 inches; dark brown (7.5YR 3/2) silty clay loam, brown (7.5YR 5/2) dry; moderate medium and coarse subangular blocky structure; slightly hard, friable, sticky and plastic; many very fine roots; common very fine and fine common very fine tubular pores; medium acid (pH 5.6); clear smooth boundary. (0 to 8 inches thick)
B21t--11 to 15 inches; brown (7.5YR 4/4) heavy silty clay, light brown (7.5YR 5/4) dry; few fine distinct red (2.5YR 4/6) and gray (5YR 5/1) mottles; moderate very fine and subangular blocky structure; hard, firm, very sticky and very plastic; many fine roots; common very fine tubular pores; few thin clay films; strongly acid (pH 5.4); clear smooth boundary. (4 to 12 inches thick)
B22t--15 to 20 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 5/3) dry; many medium distinct dark red (2.5YR 3/6), and reddish gray (5YR 5/2) mottles; moderate very fine and fine subangular blocky structure; very hard, very firm, very sticky and very plastic; common fine roots; common very fine tubular pores; many moderately thick clay films; strongly acid (pH 5.4); clear smooth boundary. (3 to 12 inches thick)
B3t--20 to 28 inches; grayish brown (10YR 5/2) clay, light brownish gray (10YR 6/2) dry; many medium and large distinct red (2.5YR 4/6 and 4/8) mottles; moderate medium and coarse subangular blocky structure; very hard, very firm, very sticky and very plastic; few very tubular pores; many intersecting slickensides; strongly acid (pH 5.2); abrupt wavy boundary. (5 to 10 inches thick)
C1--28 to 34 inches; light olive gray (5Y 6/2) clay, light gray (10YR 7/2) dry; many fine and medium prominent red (2.5YR 4/6 and 4/8) mottles; massive very hard, very firm, very sticky and very plastic; few very fine tubular pores; few nonintersecting slickensides; 15 percent strong brown (7.5YR 5/6) weathered siltstone fragments 2 to 5 mm; strongly acid (pH 5.2); clear smooth boundary. (4 to 10 inches thick)
C2--34 to 42 inches; pale brown (10YR 6/3) clay, light gray (10YR 7/2) dry; few fine prominent red (2.5YR 4/6) mottles; massive; very hard, very firm, very sticky and very plastic; 40 percent strong brown (7.5YR 5/6) weathered siltstone fragments 2 to 20 mm; very strongly acid (pH 5.0).
C3r--42 inches; partially weathered sedimentary bedrock.
TYPE LOCATION: Polk County, Oregon; .5 mile south of Dallas on county road number 8519; in the NE1/4 SE1/4 section 5, T.8S., R.5W.
RANGE IN CHARACTERISTICS: The soils are usually moist and are dry for 45 to 70 days between depths of 4 and 12 inches during the summer. The mean annual soil temperature ranges from 53 degrees to 55 degrees F. The solum typically is 20 to 36 inches thick but ranges to about 50 inches. Depth to bedrock and to the paralithic contact is 40 to 60 inches. Horizon boundaries commonly are clear in the solum but are clear or abrupt to the C1 horizon. Weathered sedimentary rock fragments range from few to 20 percent in the upper part of the C horizon and from 20 to 40 percent in the lower part of the C horizon.
The A horizon has hue of 10YR through 5YR, value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist, 2 through 4 dry. It is silt loam or silty clay loam. This horizon has moderate granular and subangular blocky structure.
The B2t horizon has hue of 7.5YR through 2.5YR, value of 4 or 5 moist, 5 through 7 dry, and chroma of 3 or 4 moist and dry. The mottling ranges from few fine to many large distinct and prominent gray and red mottles and low chroma mottles are within the upper 10 inches of the horizon. This horizon is silty clay or clay in upper part and clay in the lower part and averages 55 to 70 percent clay. It has moderate or strong subangular blocky or prismatic structure.
The C horizon has hue of 2.5Y through 7.5YR, value of 5 or 6 moist, 6 or 7 dry, and chroma of 1 through 3 moist, 2 through 4 dry. Clay ranges from 50 to 70 percent.
COMPETING SERIES: These are the Chitwood, Cumley, Dupee and Stevenson series. Chitwood soils have hue of 10YR throughout. Cumley soils lack mottles in the upper 10 inches of the argillic horizon and are moderately well drained. Dupee soils have 35 to 45 percent clay and more than 35 percent base saturation in their argillic horizon.
GEOGRAPHIC SETTING: The Suver soils have gentle to steep slopes in the eastern low foothills of the Coast Range at elevations of 275 to 800 feet. slopes range from 3 to 50 percent. The soils formed in fine textured colluvium and residuum weathered from sedimentary bedrock. The winters are cool and moist and summers are warm and dry. The average January temperature is 39 degrees F. The average July temperature is 67 degrees F. The average annual temperature is 52 degrees to 54 degrees F. The annual precipitation is 40 to 60 inches. The frost-free season is 165 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Dupee soils and the Bellpine, Jory, Rickreall and Willakenzie soils. Bellpine soils have a paralithic contact at depths of 20 to 40 inches and are well drained. Jory soils lack mottles and are well drained. Rickreall soils are 10 to 20 inches deep to a paralithic contact and are well drained. Willakenzie soils are 20 to 40 inches deep to a paralithic contact, have 27 to 35 percent clay, and are well drained.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow to rapid runoff; very slow permeability.
USE AND VEGETATION: About 50 percent of these soils are in natural vegetation of Oregon white oak, grass, wild rose, poison oak, snowberry and brackenfern. The other areas ar in pasture, cereal grains, grass seed production and abandoned orchards.
DISTRIBUTION AND EXTENT: These soil are on the low foothills of the Coast Range. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Polk County, Oregon, 1977.