LOCATION NEDHILL WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic, mesic Oxyaquic Hapludands
TYPICAL PEDON: Nedhill very gravelly medial sandy loam-forestland, on a 12 percent southeasterly aspect at an elevation of 1,600 feet in a western hemlock/salal-swordfern plant association. (Colors are for moist soil unless otherwise stated.) When described on February 4, 1992, the soil was moist throughout. (All textures are apparent field textures.)
Oi--0 to 1 inch; slightly decomposed needles, leaves, and twigs; abrupt smooth boundary. (0.5 to 2.5 inches thick)
A--1 to 7 inches; dark brown (7.5YR 3/3) very gravelly medial sandy loam, strong brown (7.5YR 4/6) dry; weak very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; weakly smeary; common very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 50 percent gravel; moderately acid (pH 5.6); clear wavy boundary. (3 to 8 inches thick)
Bw1--7 to 17 inches; dark reddish brown (5YR 3/4) very gravelly medial sandy loam, strong brown (7.5YR 4/6) dry; weak very fine and fine granular and weak very fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; weakly smeary; many medium and coarse and common very fine and fine roots; common very fine and fine irregular pores; 40 percent gravel, 10 percent cobbles; strongly acid (pH 5.4); clear wavy boundary.
Bw2--17 to 29 inches; dark brown (7.5YR 3/4) very gravelly medial sandy loam, yellowish brown (10YR 5/6) dry; weak very fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, slightly sticky and nonplastic; weakly smeary; common very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 30 percent gravel, 20 percent cobbles; strongly acid (pH 5.4); clear wavy boundary.
Bw3--29 to 36 inches; dark brown (7.5YR 3/4) very gravelly medial loam, yellowish brown (10YR 5/6) dry; weak very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; common very fine and fine and few medium roots; common very fine and fine tubular and irregular pores; 35 percent gravel, 15 percent cobbles; strongly acid (pH 5.2) abrupt wavy boundary. (Combined thickness of the Bw horizon is 17 to 35 inches.)
Cd--36 to 61 inches; dark yellowish brown (10YR 3/6) very gravelly sandy loam, brownish yellow (10YR 6/6) dry; massive; hard, brittle, nonsticky and nonplastic; 40 percent gravel, 10 percent cobbles; strongly acid (pH 5.4). (20 inches to many feet thick)
TYPE LOCATION: Mason County, Washington, about 2 miles east of Brown Creek Forest Service Campground, about 1,145 feet west and 2,550 feet north of the southeast corner of section 11, T. 22 N., R. 5 W. (Latitude 47 degrees, 24 minutes, 34 seconds N., Longitude 123 degrees, 16 minutes, 21 seconds W.)
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 47 to 51 degrees F. These soils are usually moist, and are dry 30 to 45 consecutive days in the soil moisture control section; udic moisture regime. Depth to dense till is 20 to 40 inches. The particle-size control section from the mineral soil surface to the contact with the dense layer has andic soil properties with 35 to 70 percent rock fragments by volume. The andic soil material has an estimated moist bulk density of 0.70 to 0.90 g/cc, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 2 to 4 percent, phosphate retention of 85 to 100 percent, and 15-bar water retention of 15 to 30 percent for air dried samples. Acid oxalate extractable iron is 1.5 to 3.0 percent.
The A horizon has hue of 7.5YR or 10YR moist and dry, value of 3 or 4 moist and 4 or 5 dry, and chroma of 3 or 4 moist and 4 or 6 dry. It has 10 to 20 percent organic matter.
The Bw horizon has hue of 7.5YR, 5YR, or 10YR moist and 10YR or 7.5YR dry, value of 3 or 4 moist and 4 through 6 dry, and chroma of 4 or 6 moist and dry. It is very gravelly medial sandy loam, very gravelly medial loam, or extremely gravelly medial sandy loam. It has 2 to 10 percent organic matter with less than 7 below 12 inches. It has 1 to 2 cmol/kg of aluminum.
The Cd horizon has hue of 10YR or 2.5Y moist and dry, value of 3 or 4 moist and 5 or 6 dry, and chroma of 3, 4, or 6 moist and dry. It is very gravelly sandy loam or very gravelly loam. It has moist bulk density of 1.50 to 2.00 g/cc.
COMPETING SERIES: These are the Lenacreek and Valletta series. Lenacreek and Valletta soils are well drained and are over basalt.
GEOGRAPHIC SETTING: Nedhill soils are on glacial moraines and have slopes of 5 to 60 percent. The soils formed in continental glacial till dominated by volcanic and metavolcanic rocks from local sources. Elevations are 500 to 1,600 feet. Average annual precipitation ranges from 75 to 110 inches. Average annual temperature is 45 to 49 degrees F. The frost-free season is 160 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dosewallips, Fircreek, Duskpoint and the competing Lenacreek, and Valletta soils. Dosewallips soils are on mountain slopes and shallow to bedrock. Fircreek soils are in glaciated valleys and are moderately deep to cemented till. Duskpoint soils are on glacial outwash plains and are very deep.
DRAINAGE AND PERMEABILITY: Moderately well drained; moderate over slow permeability. The subsoil is saturated for over 20 consecutive and 30 cumulative days from November through April.
USE AND VEGETATION: Timber production, wildlife habitat, recreation, and watershed. Native vegetation is western hemlock, Douglas-fir, vine maple, salal, western swordfern, red huckleberry, Oregon-grape, and northern twinflower.
DISTRIBUTION AND EXTENT: Olympic Mountains, Mason and Jefferson Counties, Washington; MLRA 1. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Mason County, Washington, 2000; Olympic National Forest.
REMARKS: Diagnostic horizons and features recognized in this pedon are the following:
Ochric epipedon
Cambic horizon - 7 to 36 inches (Bw1, Bw2, and Bw3 horizons)
Andic soil properties - 1 to 36 inches (A, Bw1, Bw2 and Bw3 horizons)
Densic layer - 36 to 61 inches (Cd layer)
PSCS - 1 to 36 inches (A, Bw1, Bw2, and Bw3 horizons)
This series also meets the saturation requirement for oxyaquic subgroup. All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.