LOCATION PIERKING WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, nonacid, frigid Typic Epiaquepts
TYPICAL PEDON: Pierking gravelly sandy loam-forested. (Colors are for moist soil unless indicated otherwise. Textures are apparent field textures)
Oe--4 to 2 inches; partially decayed leaf litter and matted roots (1 to 3 inches thick)
Oa--2 to 0 inches; well decomposed organic material, very dark brown (10YR 2/2) unrubbed, very dark grayish brown (10YR 3/2) rubbed. (2 to 12 inches thick)
A--0 to 3 inches; dark reddish brown (7.5YR 3/2) loam, grayish brown (10YR 5/2) dry; strong medium granular structure; soft, friable, nonsticky, slightly plastic; many fine and very fine roots; strongly acid (pH 5.2); abrupt wavy boundary. (2 to 7 inches thick)
Bg1--3 to 22 inches; dark brown (7.5YR 4/2) very gravelly sandy loam, pale brown (10YR 6/2) dry; many large prominent mottles, dark red (2.5YR 3/6), and reddish yellow (7.5YR 6/6); yellowish red (5YR 5/6) dry and light yellowish brown (10YR 6/4) dry; massive; hard, friable, slightly sticky, slightly plastic; common very fine roots; 35 percent pebbles; moderately acid (pH 5.6); clear smooth boundary. (6 to 20 inches thick)
Bg2--22 to 34 inches; very dark gray (N 3/0) very gravelly sandy loam, light yellowish gray (2.5YR 6/2) dry; common medium distinct mottles, dark brown (7.5YR 4/2) and dark reddish brown (5YR 3/6) brown (7.5YR 5/4) and brownish yellow (10YR 6/6) dry; massive; hard, friable, slightly sticky, slightly plastic; 45 percent pebbles; moderately acid (pH 5.6); clear smooth boundary. (6 to 18 inches thick)
Cg--34 to 60 inches; dark bluish gray (5B 4/1) very gravelly sandy loam, gray (2.N 5/0) dry; massive; hard, friable, slightly sticky, nonplastic; 50 percent pebbles; slightly acid (pH 6.2).
TYPE LOCATION: Snoqualmie Pass Area, Pierce County, Washington, 100 feet north of St. Regis Paper Company Road #2, 1,700 feet north and 2,500 feet east of the southwest corner of sec. 3, T. 16 N., R. 6 E.
RANGE IN CHARACTERISTICS: The mean annual temperature ranges from 43 degrees to 46 degrees F. The solum thickness ranges from 15 to 40 inches. Clay content in the particle-size control section is 5 to 18 percent. Rock fragments range from 35 to 55 percent by weighted average, although individual horizons have 15 to 60 percent rock fragments.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3 moist, 4 or 5 dry, and chroma of 1 or 2 moist and dry. Reaction is strongly acid or medium acid.
The Bg horizon has hue of 10YR, 2.5Y, or neutral value of 3 through 5 moist, 5 or 6 dry, and a chroma of 0 through 2 moist and dry. Mottles range from faint to prominent, and colors have a hue of 2.5YR through 7.5YR, value of 3 through 6, and chroma of 2 through 6 moist and dry. It is gravelly sandy loam or very gravelly sandy loam. Reaction is strongly acid or medium acid.
The Cg horizon has hue of 10YR, 2.5Y, 5Y, 5B or 5Bg or neutral, value of 3 through 5 moist, 5 through 7 dry, and chroma of 0 through 2 moist or dry. It is very gravelly sandy loam or very gravelly loamy sand. Reaction is strongly acid through slightly acid. Mottles are faint or distinct and have hue of 5YR or 7.5YR, value of 3 through 5 moist, 4 through 6 dry, and value of 4 through 8 moist and dry.
COMPETING SOILS: These are the similar McKenna and Poverty soils. McKenna soils are mesic. Poverty soils are sandy-skeletal.
GEOGRAPHIC SETTING: Pierking soils are on river terraces and areas adjacent to river terraces. Slopes are 0 to 15 percent. Elevation ranges from 1,200 to 2,000 feet. These soils formed in recent volcanic mud flow deposits and alluvium. Pierking soils are in a marine climate with cold, wet winters and cool, dry summers. Average annual precipitation ranges from 60 to 80 inches. The mean January temperature is about 33 degrees F and the mean July temperature is about 59 degrees F; the mean annual temperature is about 46 degrees F. The frost-free season is 110 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Zynbar, Ovall, Ohop, Lemolo, and Greenwater soils. The Ovall soils are mesic and have a lithic contact at a depth of 20 to 40 inches. Zynbar soils are medial. Ohop soils have a udic moisture regime. Greenwater soils are sandy. Lemolo soils have an umbric epipedon and are mesic.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; very slow runoff; permeability is moderate. A perched water table is as high as 0.5 to 1 foot from November through March. This soil is subject to rare periods of flooding.
USE AND VEGETATION: Used for timber production, watershed, and wildlife habitat. Native plant species are western hemlock, western redcedar, black cottonwood, red alder, Sitka spruce, Douglas-fir, and grand fir, with an undergrowth of devils club, skunk cabbage, lady fern, western swordfern, vine maple, Oregon-grape, red huckleberry, miners lettuce, trailing blackberry, Oregon oxalis, salmonberry, horsetail, and elksedge.
DISTRIBUTION AND EXTENT: River Valleys in the foothills on the west slopes of the Cascade Mountains adjacent to Mt. Rainier, Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Snoqualmie Pass Area, Pierce County, Washington, 1986.
REMARKS: Diagnostic horizon and features recognized in this pedon are an ochric epipedon from the mineral surface to 3 inches and a gleyed cambic horizon from 3 to 34 inches.