LOCATION DUSKPOINT WAEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, isotic, mesic Typic Hapludands
TYPICAL PEDON: Duskpoint very gravelly medial loam - forestland, on a 3 percent slope with a northwesterly aspect at an elevation of 1,020 feet in a western hemlock/salal plant association. (When described on January 13, 1992, the soil was moist throughout. Colors are for moist soil unless otherwise stated. All textures are apparent field textures.)
Oi--0 to 1 inch; slightly decomposed needles, leaves, and twigs; abrupt wavy boundary. (1 to 2 inches thick)
A--1 to 6 inches; dark brown (7.5YR 3/3) very gravelly medial loam, strong brown (7.5YR 4/6) dry; weak very fine, fine, and medium granular structure; soft, very friable, nonsticky and nonplastic; weakly smeary; common very fine, fine, medium, and coarse roots; common very fine and fine irregular and tubular pores; 50 percent gravel; strongly acid (pH 5.4); clear wavy boundary. (5 to 7 inches thick)
Bw--6 to 16 inches; dark brown (7.5YR 3/4) very gravelly medial sandy loam, yellowish brown (10YR 5/6) dry; weak very fine and fine granular and weak very fine and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; weakly smeary; common very fine and fine and few medium and coarse roots; common very fine and fine irregular pores; 50 percent gravel, 5 percent cobbles; moderately acid (pH 5.6); clear wavy boundary. (9 to 13 inches thick)
2C1--16 to 20 inches; dark yellowish brown (10YR 3/6) extremely gravelly sand, yellowish brown (10YR 5/6) dry; single grain; loose, nonsticky and nonplastic; common very fine and few fine roots; 55 percent gravel, 10 percent cobbles; moderately acid (pH 6.0); clear wavy boundary. (3 to 9 inches thick)
2C2--20 to 61 inches; dark olive brown (2.5Y 3/3) extremely gravelly sand, light olive brown (2.5Y 5/3) dry; single grained; loose, nonsticky and nonplastic; few very fine roots; 60 percent gravel, 15 percent cobbles; slightly acid (pH 6.4).
TYPE LOCATION: Mason County, Washington, about 2 miles east-northeast of the Brown Creek Campground, about 1,320 feet east and 2,350 feet north of the southwest corner of Section 2, T. 22 N., R. 5 W. (Latitude 47 degrees, 25 minutes, 24 seconds N., Longitude 123 degrees, 17 minutes, 00 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 the sandy-skeletal substratum is 14 to 20 inches. particle-size control section has andic soil properties with a cumulative thickness of 14 to 20 inches and 40 to 85 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 3 percent, phosphate retention of 85 to 100 percent and 15-bar water retention of 12 to 25 percent for air dried samples, and acid oxalate extractable iron of 1.5 to 3.0 percent. The lower part (thickest part) of the particle-size control section lacks andic soil properties.
The A horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, and chroma of 3 or 4 moist and 4 or 6 dry. It has 2 to 5 cmol/kg of aluminum. It has 5 to 15 percent organic matter.
The Bw horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist and 5 or 6 dry, and chroma of 4 or 6 moist. It is very gravelly medial sandy loam, very cobbly medial sandy loam, or extremely gravelly memdial sandy loam. Reaction is moderately or strongly acid. It has 1 to 2 cmol/kg of aluminum. It has 1 to 7 percent organic matter.
The 2C horizon has value of 3 or 4 moist and 6 or 7 dry, and chroma of 4 or 6 moist or dry. It is extremely gravelly sand, extremely gravelly loamy sand, extremely cobbly loamy sand or extremely cobbly sand. Reaction is slightly or moderately acid.
COMPETING SERIES: There are no competing series. The Nanich series is similar; Nanich soils are isomesic.
GEOGRAPHIC SETTING: Duskpoint soils are in glacial valleys. Slopes are 2 to 15 percent. The soils formed in glacial outwash deposits. Elevations are 800 to 1,100 feet. Average annual precipitation ranges from 100 to 120 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, Govey, Lenacreek, Nedhill, and Valletta soils. Dosewallips soils are on mountain slopes and are shallow to bedrock. Fircreek and Govey soils are on glacial valleys and are moderately deep to cemented till. Lenacreek soils are on mountain slopes and are moderately deep to bedrock. Nedhill soils are on glacial valleys and are moderately deep to dense till. Valletta soils are on mountain slopes and are medial-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; moderate over rapid permeability.
USE AND VEGETATION: Timber production, wildlife habitat, recreation, and watershed. Native vegetation is western hemlock, Douglas-fir, salal, red huckleberry, Oregon-grape, and northern twinflower.
DISTRIBUTION AND EXTENT: Mason County, 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: an ochric epipedon, a cambic horizon from 6 to 16 inches and andic soil properties from the mineral soil surface to 16 inches. The particle-size control section is the zone from 1 to 41 inches with 1 to 16 inches being medial-skeletal and ferrihydritic and 16 to 41 inches being sandy-skeletal and isotic. The thickest part is sandy-skeletal.
All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.