LOCATION THIRTYCENT WA

Established Series
Rev. EED/TDT
12/2010

THIRTYCENT SERIES

The Thirtycent series consists of deep, moderately well drained soils formed in glaciolacustrine sediment. Thirtycent soils are on sideslopes and noseslopes of glacially modified hills. Slopes are 0 to 20 percent. Mean annual precipitation is about 110 inches and the mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Medial over loamy-skeletal, ferrihydritic over isotic, isofrigid Aquic Fulvudands

TYPICAL PEDON: Thirtycent gravelly medial loam, on a northwest facing slope of 12 percent at 850 feet elevation under coniferous forest vegetation. (Colors are for moist soil unless otherwise noted.)

Oi--0 to 2 inches; slightly decomposed plant material; abrupt smooth boundary. (1 to 4 inches thick)

A--2 to 4 inches; very dark grayish brown (10YR 3/2) gravelly medial loam, dark brown (10YR 3/3) dry; moderate medium granular structure; soft, very friable, nonsticky, nonplastic; few medium roots and many very fine roots; common fine irregular pores; 15 percent gravel; extremely acid (pH 4.3); abrupt wavy boundary. (1 to 5 inches thick)

Bw--4 to 35 inches; dark yellowish brown (10YR 3/4) gravelly medial silt loam, dark yellowish brown (10YR 4/6) dry; moderate medium subangular blocky structure; soft, very friable, slightly sticky, moderately plastic; few very fine and coarse roots and common fine and very coarse; common fine irregular pores; 15 percent gravel and 5 percent cobbles; extremely acid (pH 4.3); abrupt wavy boundary. (15 to 35 inches thick)

2Bg--35 to 49 inches; olive brown (2.5Y 4/3) very cobbly loam, olive brown (2.5Y 4/4) dry; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common fine and medium roots between peds; common fine irregular pores; common coarse prominent brownish yellow (10YR 6/8) dry, and yellowish brown (10YR 5/8) moist, iron-manganese masses on ped faces and many coarse prominent light gray (10YR 7/1) dry, and gray (10YR 6/1) moist, iron depletions on ped faces; 25 percent gravel and 25 percent cobbles; slightly acid (pH 6.4); abrupt wavy boundary. (10 to 20 inches thick)

2Cd--49 to 60 inches; very dark grayish brown (2.5Y 3/2) gravelly clay loam, dark grayish brown (2.5Y 4/2) dry; massive; hard, firm, very sticky, very plastic; few fine roots in cracks; few fine tubular pores; common fine prominent yellowish brown (10YR 5/8) moist, and brownish yellow (10YR 6/8) dry, iron-manganese masses on ped faces and common fine prominent gray (10YR 6/1) moist, and light gray (10YR 7/1) dry, iron depletions on ped faces; 15 percent gravel; slightly alkaline (pH 7.8).

TYPE LOCATION: Clallam County, Washington; Neah Bay, Washington USGS quadrangle; 48 degrees, 17 minutes, 55.00 seconds north latitude and 124 degrees, 35 minutes, 1.00 second west longitude.

RANGE IN CHARACTERISTICS: Depths to diagnostic horizons and features start from the mineral soil surface.

Mean annual soil temperature - 41 to 45 degrees F
Soil moisture control section - dry 0 to 30 consecutive days
Depth to redoximorphic features - 20 to 40 inches
Depth to densic contact - 40 to 60 inches

A horizon
Hue - 7.5YR or 10YR
Value - 2, 2.5, or 3 moist, 3 or 4 dry
Chroma - 2 or 3, moist or dry
Organic matter - 15 to 25 percent
Bulk density - 0.70 to 0.90 g/cm3
Phosphate retention - 85 to 100
Ammonium oxalate extractable aluminum plus one half iron - 2 to 5 percent
Reaction - Extremely acid to strongly acid
Clay content - 5 to 18 percent field estimate
Rock fragments - 15 to 25 percent gravel

Bw horizon
Hue - 7.5YR or 10YR
Value - 3 or 5 moist, 4 or 5 dry
Chroma - 4 to 6 moist or dry
Organic matter - 10 to 20 percent
Bulk density - 0.70 to 0.90 g/cm3
Phosphate retention - 85 to 100
Ammonium oxalate extractable aluminum plus one half iron - 2 to 5 percent
Reaction - Extremely acid to strongly acid
Clay content - 18 to 27 percent field estimate
Texture - GR-MEDL-SIL, MEDL-L
Rock fragments - 0 to 25 percent gravel, 0 to 5 percent cobbles, 0 to 25 percent total.

2Bg horizon
Hue - 2.5Y or 10YR
Value - 3 or 4 moist, 4 or 5 dry
Chroma - 3 to 4 moist, 4 to 6 dry
Organic matter - .5 to 1 percent
Bulk density - 1.30 to 1.50 g/cm3
Reaction - Slightly acid to neutral
Clay content - 18 to 27 percent field estimate
Texture - CBV-L, GRV-SIL
Rock fragments - 10 to 35 percent gravel, 0 to 25 percent cobbles, 0 to 5 percent stones, 35 to 60 percent total.

2Cd horizon
Hue - 2.5Y or 5Y
Value - 3 or 4 moist or dry
Chroma - 2 or 3 moist or dry
Organic matter - .5 to 1 percent
Bulk density - 1.70 to 1.90 g/cm3
Reaction - Slightly acid to moderately alkaline
Clay content - 18 to 35 percent field estimate
Texture - GR-CL, SICL, SIL
Rock fragments - 10 to 35 percent gravel, 0 to 25 percent cobbles, 0 to 5 percent stones, 35 to 60 percent total.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Thirtycent soils occur on sideslopes and noseslopes of glacially modified hills at elevations of 400 to 950 feet. Slopes are 0 to 20 percent. These soils formed in glaciolacustrine sediments. The climate is characterized by cool, wet winters and cool, dry summers. Mean annual precipitation ranges from 90 to 120 inches. Mean annual air temperature is 40 to 44 degrees F. The frost-free period is 120 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aabab, Stolzenberg, and Tealwhit soils. Aabab and Tealwhit soils occur along adjacent drainageways. Stolzenberg soils occur on adjacent noseslopes and summits.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; Saturated hydraulic conductivity in the A, Bw, and 2Bg horizons is moderately high and low to moderately low in the 2Cd horizon.

USE AND VEGETATION: Used for timber production, recreation, wildlife habitat, homesites, and watershed. Potential natural vegetation consists of Pacific silver fir, Sitka spruce, Sitka mountain ash, western redcedar, Alaska huckleberry, deer fern, evergreen huckleberry, fool's huckleberry, red huckleberry, salal, salmonberry, thimbleberry, and western swordfern.

DISTRIBUTION AND EXTENT: Washington MLRA 4A. Series is of small extent.

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

SERIES ESTABLISHED: Clallam County, Washington, 2010.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon
Andic soil properties - 2 to 35 inches
Particle size control section - 2 to 42 inches (A, Bw, and part of the 2Bg horizon)
Cambic horizon - 4 to 35 inches (Bw horizons)
Depth to redoximorphic features - 35 inches (depletions with chroma of 2 or less and iron masses)
Densic contact - 49 inches (2Cd horizon)

National Cooperative Soil Survey
U.S.A.