LOCATION HOH                     WA

Established Series
Rev. FRM/LJH/RJE
02/2011

HOH SERIES

The Hoh series consists of very deep, moderately well or well drained soil that formed in mixed alluvium. These soils are on low terraces and flood plains and have slopes of 0 to 10 percent. The mean annual precipitation is about 110 inches and the mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Coarse-loamy, isotic, isomesic Andic Dystrudepts

TYPICAL PEDON: Hoh medial silt loam, forested. (Colors are for moist soil unless otherwise noted. All textures are apparent field textures.)

Oe--0 to 2 inches; moderately decomposed leaves, needles, and wood fragments.

A--2 to 7 inches; dark reddish brown (5YR 2/2) medial silt loam, dark reddish gray (5YR 4/2) dry; moderate fine granular structure; slightly hard, friable, nonsticky and nonplastic; common fine and medium roots; porous; few fine soft concretions; very strongly acid (pH 5.0); clear smooth boundary. (1 to 6 inches thick)

Bw--7 to 15 inches; dark grayish brown (10YR 4/2) medial silt loam, light brownish gray (10YR 6/2) dry; weak fine and medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common fine and medium roots; many fine tubular pores; strongly acid (pH 5.2); gradual smooth boundary. (6 to 8 inches thick)

2C1--15 to 23 inches; dark grayish brown (10YR 4/2) very fine sandy loam, light brownish gray (10YR 6/2) dry; massive; soft friable, nonsticky and nonplastic; common fine roots; many fine tubular pores; strongly acid (pH 5.2); gradual smooth boundary. (0 to 20 inches thick)

2C2--23 to 38 inches; very dark grayish brown (2.5Y 3/2) fine sandy loam, grayish brown (2.5Y 5/2) dry; massive; soft, friable, nonsticky and nonplastic; few fine roots; many fine tubular pores; strongly acid (pH 5.3); clear smooth boundary. (0 to 30 inches thick)

3C3--38 to 44 inches; very dark grayish brown (2.5Y 3/2) gravelly fine sandy loam, grayish brown (2.5Y 5/2) dry; massive; soft, very friable, nonsticky and nonplastic; 20 percent gravel; few fine roots; strongly acid (pH 5.4). (0 to 18 inches thick)

4C4--44 to 62 inches; very dark gray (5Y 3/1) extremely gravelly coarse sand, gray (5Y 5/1) dry; single grained; loose; 60 percent gravel, 10 percent cobbles; strongly acid (pH 5.5).

TYPE LOCATION: Jefferson County, Washington; 2.7 miles southwest of junction of U. S. Highway 101 and Lower Hoh River Road, and 0.8 mile south to end of logging road; 150 feet from river bank in NW1/4 NW1/4 NW1/4 sec. 8, T.27N., R.12W.

RANGE IN CHARACTERISTICS: Depth to sand or gravelly sand layer is more than 40 inches. The particle-size control section is 0 to 15 percent coarse fragments. The mean annual soil temperature is estimated to range from 47 to 52 degrees F. The difference between the mean summer and mean winter soil temperature is 5 to 9 degrees F. The upper 7 to 14 inches of mineral soil has andic soil properties with a moist bulk density of 0.75 to 0.90 g/cc, acid oxalate extractable aluminum plus one-half the iron is 3 to 4 percent, phosphate retention is 85 to 100 percent and 15-bar water retention is 20 to 30 percent for air-dried samples. Base saturation is less than 35 percent throughout the profile.

The A and Bw horizon has hue of 5YR through 2.5Y, value of 2 through 4 moist, 3 to 6 dry and chroma of 2 and 3. It is strongly acid or very strongly acid. Some pedons have thin dark yellowish brown bands of iron cementation or iron stains. It has 2 to 3 cmol/kg of aluminum. It has 10 to 25 percent organic matter.

The 2C horizon has value of 3 through 5 moist and chroma of 1 through 4 moist and 1 through 3 dry. The low chromas are inherited from the parent material. This horizon is mostly stratified silt loam, very fine sandy loam, fine sandy loam and sandy loam, with thin layers (less than 3 inches tick) of fine sand, sand and loamy sand.

The 3C and 4C horizons are coarsely stratified fine sandy loam, sand, loamy sand, gravelly fine sandy loam, very gravelly sand, and extremely gravelly coarse sand. It is strongly acid or very strongly acid. Some pedons have dark yellowish brown and olive brown iron stains.

COMPETING SERIES: This is the Clevescove series. Clevescove soils have an umbric epipedon and a paralithic contact at 40 to 60 inches.

GEOGRAPHIC SETTING: Hoh soils are on flood plains and low terraces at elevations of 0 to 500 feet. Slopes are 0 to 10 percent. These soils formed in mixed alluvium. The climate is characterized by cool, wet winters and cool, moist summers. Mean annual precipitation is 90 to 140 inches. Average January temperature is about 39 degrees F., average July temperature is about 60 degrees F., and the mean annual temperature is about 50 degrees F. The frost-free season is 160 to 220 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chowchow, Huel, Kalaloch, Nuby and Queets soils. Huel soils are sandy-skeletal. Kalaloch and Queets soils have over 14 inches of andic soil material and are Fulvudands. Kalaloch soils are medial over sandy or sandy-skeletal and Queets soils are medial. Nuby are poorly drained.

DRAINAGE AND PERMEABILITY: Moderately well or well drained; medium runoff; moderate over very rapid permeability. These soil are subject to rare or occasional flooding. These soils have a perched water table at the substratum contact for very brief to brief periods during intense rainfall events.

USE AND VEGETATION: These soils are used primarily for timber production but small areas are in permanent pasture or homesites. Native
vegetation is western hemlock, Sitka spruce, western redcedar, redalder, bigleaf maple, and vine maple. Understory species include red huckleberry, salmonberry, western swordfern, deer fern and ladyfern.

DISTRIBUTION AND EXTENT: Northwestern Olympic Peninsula, Washington; MLRA 4A. Series is of small extent.

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

SERIES ESTABLISHED: Jefferson County, Washington, 1971.

REMARKS: Diagnostic horizons and other features.
Cambic horizon - 7 to 15 inches
Andic soil properties - 2 to 15 inches
Particle-size control section - 12 to 42 inches; 12 to 15 inches is medial and 15 to 42 inches is coarse-loamy. The medial portion does not extend 4 inches into the upper part and is not contrasting.
All depths to diagnostic horizons and features are measured from the top of the first mineral horizon.

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National Cooperative Soil Survey
U.S.A.