LOCATION SOLDUC             WA
Established Series
Rev. LJH/RJE
08/2007

SOLDUC SERIES


The Solduc series consists of very deep, somewhat excessively drained soils that formed in glacial outwash on glacial outwash plains or terraces and associated escarpments. Slopes are 0 to 65 percent. The mean annual precipitation is about 105 inches and the mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Medial-skeletal over sandy or sandy-skeletal, ferrihydritic over mixed, isomesic Typic Fulvudands

TYPICAL PEDON: Solduc very gravelly medial sandy loam, forested. (Colors are for moist soil unless otherwise noted. All textures are apparent field textures.)

Oi--0 to 2 inches; slightly decomposed needles, leaves, and twigs.

A--2 to 9 inches; dark reddish brown (5YR 3/2) very gravelly medial sandy loam, reddish brown (5YR 4/3) dry weak very fine subangular blocky, and very fine and fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; many very fine, fine and medium roots; many very fine and fine irregular, and many very fine tubular pores; 40 percent pebbles and 5 percent cobbles; very strongly acid (pH 4.6); clear smooth boundary. (3 to 8 inches thick)

Bw1--9 to 14 inches; dark reddish brown (5YR 3/4) extremely gravelly medial sandy loam, brown (7.5YR 4/4) dry; weak fine and very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; many very fine, fine and medium roots; many fine and very fine irregular pores and tubular pores; 50 percent pebbles and 10 percent cobbles; very strongly acid (pH 4.8); clear smooth boundary. (5 to 12 inches thick)

Bw2--14 to 32 inches; brown (7.5YR 4/4) extremely gravelly medial sandy loam, reddish yellow (7.5YR 6/6) dry; weak very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; many very fine and fine, and common medium roots; many fine and very fine irregular and tubular pores; 50 percent pebbles and 10 percent cobbles; very strongly acid (pH 5.0); clear smooth boundary. (10 to 20 inches thick)

2C1--32 to 54 inches; dark yellowish brown (10YR 4/4) extremely gravelly loamy sand, brownish yellow (10YR 6/6) dry; single grained; loose; common fine and very fine, and few medium roots; many fine and very fine irregular, and common very fine tubular pores; 50 percent pebbles and 20 percent cobbles; very strongly acid (pH 5.0); clear smooth boundary. (18 to 22 inches thick)

2C2--54 to 62 inches; dark grayish brown (2.5Y 4/2) extremely gravelly sand, light olive brown (2.5Y 5/4) dry; single grained; loose; common fine and very fine roots; many fine and very fine irregular pores; 50 percent pebbles and 20 percent cobbles; very strongly acid (pH 5.0).

TYPE LOCATION: Clallam County, Washington; 1,400 feet south and 2,400 feet west of the NE corner of section 29, T.29N., R.13W. (Near gravel pit)

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 51 degrees F. The difference between the mean summer and mean winter soil temperature is 5 to 9 degrees F. The soil moisture control section is dry for 30 to 45 consecutive days; udic moisture regime. The solum thickness and depth to sandy-skeletal material is 20 to 40 inches. The solum has andic soil properties with moist bulk density of 0.50 to 0.90 g/cc, phosphate retention of 85 to 100, acid oxalate extractable aluminum plus one-half the acid oxalate iron of 2 to 4 percent and 15 bar water of 15 to 30 percent on air-dried samples. Acid oxalate extractable iron is 1.5 to 3.0 percent. It is very strongly or strongly acid throughout the profile. The lower part (thinnest part) of the particle-size control section lacks andic soil properties.

The A horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 through 4. It has 10 to 20 percent organic matter. It has 4 to 8 cmol/kg of aluminum.

The Bw horizon has hue of 7.5YR or 10YR, value of 3 or 4 moist, 4 through 6 dry, and chroma of 4 or 6. It is very gravelly medial sandy loam, extremely gravelly medial sandy loam, or very gravelly medial loam. It has 5 to 15 percent organic matter, dropping to less than 7 percent below a depth of 15 inches from the mineral soil surface. It has 2 to 3 cmol/kg of aluminum.
Some pedons have a BC or 2CB horizon with hue of 10YR, value of 4 moist, 5 or 6 dry, and chroma of 6. It is very gravelly medial sandy loam or extremely gravelly loamy sand.

The 2C horizon has value of 3 or 4 moist and chroma of 2 through 6 moist. It is extremely gravelly loamy sand, extremely cobbly loamy sand, extremely gravelly sand, or extremely cobbly sand.

COMPETING SERIES: These are the Ascar, Grismar, Klone, Mudcreek, Necanicum, Southshore and Traham series. Ascar and Traham soils are moderately deep to bedrock. Necanicum soils are on mountain, very deep and lack the contrasting sandy-skeletal substratum. Klone soils are 40 to 60 inches deep to sandy-skeletal substratum. Mudcreek soils are moderately deep to dense till. Southshore soils are deep to cemented till. Grismar soils are on mountains.

GEOGRAPHIC SETTING: Solduc soils are on terraces and terrace escarpments at elevations of 50 to 900 feet. They formed in glacial outwash. The soils are in a mild marine climate and have cool, moist summers and cool, wet winters. The mean annual precipitation is 80 to 125 inches. The average January temperature is about 38 degrees F.; the average July temperature is about 61 degrees F.; and the mean annual temperature is about 45 to 49 degrees F. The frost free season is 140 to 220 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Nanich, Queets and the Quillayute soils. Nanich soils have a sandy-skeletal substratum at 14 to 20 inches. Queets and Quillayute soils are medial and lack the sandy-skeletal substratum.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; medium runoff; permeability of the subsoil is moderate and permeability of the substratum is rapid.

USE AND VEGETATION: Timber production is the principal use. Native vegetation is western hemlock, Douglas fir, Sitka spruce, red huckleberry, salal, vine maple, cascara buckethorn, devil's club, salmonberry, elder, twinflower, western swordfern, deer fern, ladyfern and bedstraw.

DISTRIBUTION AND EXTENT: Western Clallam County, Washington; MLRA 4A. This series is moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Clallam County, Washington, 1943.

REMARKS: Diagnostic horizons and other features:
- ochric epipedon
- cambic horizon - 9 to 32 inches
- andic soil properties - 2 to 32 inches
- particle-size control section - 2 to 42 inches; 2 to 32 inches is medial-skeletal and 32 to 42 inches is sandy-skeletal
- all depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.

ADDITIONAL DATA: National Soil Survey Laboratory, sample numbers S77WA9-6-1 through 9-6-5 and S77WA9-7-1 through 9-7-4.


National Cooperative Soil Survey
U.S.A.