LOCATION SAUVIE OR+WAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Fluvaquentic Endoaquolls
TYPICAL PEDON: Sauvie silty clay loam, cultivated. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 9 inches; very dark grayish brown (10YR 3/2) silty clay loam, grayish brown (10YR 5/2) dry; common fine faint dark brown (10YR 3/3) mottles; strong fine subangular blocky structure; friable, slightly sticky and slightly plastic; many very fine roots; many very fine pores; few fine concretions; slightly acid (pH 6.2); abrupt smooth boundary. (5 to 9 inches thick)
A12--9 to 15 inches; very dark grayish brown (10YR 3/2) silty clay loam, grayish brown (10YR 5/2) dry; many fine distinct dark brown (7.5YR 4/4) mottles; moderate fine subangular blocky structure; firm, slightly sticky and slightly plastic, common fine roots; many very fine pores; slightly acid (pH 6.2); clear smooth boundary. (5 to 7 inches thick)
B21g--15 to 18 inches; very dark grayish brown (10YR 3/2) silty clay loam; many fine distinct dark brown (7.5YR 3/2) and dark yellowish brown (10YR 4/4) mottles; moderate fine subangular blocky structure; firm, slightly sticky and plastic; medium acid (pH 6.0); abrupt smooth boundary. (0 to 8 inches thick)
B22g--18 to 27 inches; dark grayish brown (10YR 4/2) silty clay loam; many fine distinct gray (N 5/) and dark brown (7.5YR 3/2) mottles; weak fine subangular blocky structure; firm, sticky and plastic; few fine roots; common fine pores; slightly acid (pH 6.2); clear smooth boundary. (6 to 15 inches thick)
B3g--27 to 39 inches; dark grayish brown (10YR 4/2) silty clay loam; many fine and medium distinct gray (N 5/) and dark brown (7.5YR 3/2) mottles; weak medium subangular blocky structure; firm, slightly sticky and slightly plastic; slightly acid (pH 6.2); abrupt smooth boundary. (10 to 13 inches thick)
C--39 to 48 inches; dark grayish brown (10YR 4/2) very fine sandy loam; many fine and medium distinct dark brown (7.5YR 3/2), grayish brown (10YR 5/2), and gray (N 5/) mottles; massive; friable, nonsticky and nonplastic; many very fine pores; slightly acid (pH 6.4).
TYPE LOCATION: Multnomah County, Oregon; along a field road, 800 feet northwest from the Gillahan loop road; SW1/4 NW1/4 sec. 14, T.2N., R.1W.
RANGE IN CHARACTERISTICS: The soils are saturated with water from about December through June and are subject to freshwater overflow during high tides unless diked and artificially drained. The mean annual soil temperature ranges from 53 degrees to 55 degrees F. Soil depth is over 5 feet, but rooting depth may be limited to less than 30 inches by a seasonal watertable. The 10- to 40-inch control section averages 25 to 35 percent clay. The mollic epipedon is 10 to 24 inches thick and has distinct mottles in the lower part.
The A horizon is usually silty clay loam and ranges to silt loam. It has strong to moderate subangular or angular blocky structure. A thin overwash of sand or fine sand less than 4 inches thick overlies the A horizon in some areas.
The B horizon has value of 3 or 4 moist. It has mottles that are distinct in the upper part and distinct to prominent in the lower part. It is silty clay loam or silt loam. In some pedons this horizon has thin lenses of peaty material or loamy material with moist value of 2 or 3 and moist chroma of 1 in 10YR hue.
The C horizon has hue of 10YR, 2.5Y or neutral, value of 4 or 5 moist, and chroma of 0 through 2. It is composed of stratified material ranging from sandy loam to silt loam. Mottles are distinct with some areas having dark brown (7.5YR 3/2) "pipestems" up to 1/4 inch in diameter formed in tubular pores and channels. Thin layers of gray (10YR 6/1) ashlike material are in some pedons.
COMPETING SERIES: These are the Beaucoup, Blackoar, Bridgeson, Gorham, Lummi, and Wapato series. Beaucoup and Gorham soils lack influence of ash and are moist in the summer. Also, Beaucoup soils have solum thickness of 40 to 60 inches. Blackoar and Lummi soils have 18 to 27 percent clay in the 10- to 40-inch section. Also, Lummi soils are affected by tidal salt water. Bridgeson soils are neutral, have chroma of 1 in the A horizon, and are moderately fine textured in the lower Cg horizon. Wapato soils are fine textured in the lower part of the control section.
GEOGRAPHIC SETTING: The Sauvie soils are on flood plains along the lower Columbia River and its tributaries. Slopes are 0 to 3 percent. The soils formed in recent alluvium with some mixing with volcanic ash. They are at elevations of 10 to 40 feet in a climate with cool dry summers and cool moist winters. Annual precipitation is 40 to 60 inches. Average July temperature is 66 degrees to 68 degrees F., average January temperature is 38 degrees to 40 degrees F., and average annual temperature is 52 degrees to 54 degrees F. The average frost-free period is 165 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Moag, Rafton, Pilchuck, and Sifton soils. Moag and Rafton soils are very poorly drained and lack a mollic epipedon. Pilchuck soils are sandy. Sifton soils are medial over sandy or sandy-skeletal.
DRAINAGE AND PERMEABILITY: Poorly drained; slow runoff; moderately slow permeability.
USE AND VEGETATION: When diked and drained, the soils are used for improved hay and pasture, small grain, and truck corps. Areas outside of dike are in native vegetation or used for hay and pasture and commercial waterfowl areas. The native vegetation is red alder, ash, willow, cottonwood, grasses and tussocks.
DISTRIBUTION AND EXTENT: Southwesten Washington and northwestern Oregon along the Columbia River and its tributaries west of the Cascade Range. The soil is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Multnomah County, Oregon, 1919.
REMARKS: As originally mapped the series had a much wider range in soil characteristics.