LOCATION PENNYCREEK WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, acid, frigid Lithic Xerorthents
TYPICAL PEDON: Pennycreek extremely gravelly sandy loam - forestland, on a 72 percent west-facing slope at an elevation of 2,765 feet in a mountain hemlock/Pacific rhododeneron-salal plant association. (When described on May 26, 1993 the soil was moist throughout. Colors are for dry soil unless otherwise stated.)
Oi--0 to 1 inch; slightly decomposed needles, twigs, and leaves; abrupt smooth boundary. (1 to 2.5 inches thick)
A1--1 to 4 inches; brown (10YR 5/3) extremely gravelly sandy loam, dark brown (10YR 3/3) moist; weak very fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; many very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 55 percent gravel, 5 percent cobbles; strongly acid (pH 5.4); clear smooth boundary. (2 to 5 inches thick)
A2--4 to 10 inches; yellowish brown (10YR 5/4) extremely gravelly sandy loam, dark yellowish brown (10YR 3/4) moist; weak very fine and fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; many very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 55 percent gravel, 15 percent cobbles; strongly acid (pH 5.4); abrupt wavy boundary. (2 to 8 inches thick)
R--10 inches; hard metavolcanic rock.
TYPE LOCATION: Clallam County, Washington, about 2 1/4 miles east of the Gold Creek Shelter, about 2,510 feet east and 200 feet north of the southwest corner of section 3, T. 28 N., R. 3 W. (Latitude 47 degrees, 56 minutes, 23 seconds N., Longitude 123 degrees, 02 minutes, 41 seconds W.)
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 45 to 47 degrees F. These soils are usually moist but are dry in all parts of the soil moisture control section for 45 to 60 consecutive days in the 4 months following the summer solstice. Depth to bedrock is 4 to 10 inches. The particle-size control section has 60 to 90 percent rock fragments by volume and 5 to 18 percent clay. Base saturation by ammonium acetate is 75 to 90 percent throughout.
The A horizon has value of 5 through 7 dry, 3 or 5 moist, and chroma of 3 through 6 dry and moist. It is extremely gravelly sandy loam or extremely cobbly loam. It has 2 to 6 percent organic matter. Moist bulk density is 0.90 to 1.00 g/cc. Acid oxalate aluminum plus one-half the acid oxalate iron is 1 to 2 percent.
COMPETING SERIES: There are no competing series in this family.
GEOGRAPHIC SETTING: Pennycreek soils are on mountain slopes and have slopes of 60 to 90 percent. The soils formed in colluvium from marine basalt and associated volcanic rocks. Elevations are 2,100 to 3,100 feet. Average annual precipitation is 35 to 70 inches. Average annual temperature is 44 to 46 degrees F. The frost-free season is 160 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Graywolf, Halfoss, Juandefuca, Maidenpeak, Slidecamp, Station, and Tunnelcreek soils. Graywolf soils are on low relief dissected uplands and have an argillic horizon. Halfoss and Tunnelcreek soils are on mountain slopes and are 20 to 40 inches to bedrock. Juandefuca and Maidenpeak soils are on mountain slopes and are very deep. Slidecamp soils are on low relief dissected uplands and have an argillic horizon with less than 35 percent rock fragments. Station soils are on mountain slopes and have a udic moisture regime.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.
USE AND VEGETATION: Wildlife habitat, recreation, and watershed. Native vegetation is Douglas-fir, mountain hemlock, western redcedar, Pacific rhododendron, salal, Oregon-grape, northern twinflower, and creambush oceanspray.
DISTRIBUTION AND EXTENT: Clallam and Jefferson Counties, Washington; MLRA 2. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clallam County, Washington, 2000; Olympic National Forest.
REMARKS: Diagnostic horizons and features recognized in this pedon are the following:
Ochric epipedon
Lithic contact - 10 inches
PSCS - is 1 to 10 inches
Xeric moisture regime
All depths to diagnostic horizons or other features are measured from the top of the first mineral horizon.