LOCATION WILLAPA                 WA

Established Series
Rev. DRU/EED/
02/2017

WILLAPA SERIES

Landscape--coastal plains
Landform--marine terraces
Slope--1 to 65 percent
Parent material--loess and stratified marine deposits
Mean annual precipitation--2300 mm
Mean annual air temperature--8 degrees C
Depth class--very deep
Drainage class--moderately well drained
Soil moisture regime--udic
Soil temperature regime--isomesic
Soil moisture subclass--aquic

TAXONOMIC CLASS: Medial, ferrihydritic, isomesic Aquic Fulvudands

TYPICAL PEDON: Willapa medial silt loam on a forested, southeast-facing, 20-percent slope at an elevation of 9 m (When described, the soil was moist throughout.)

Oi--0 to 5 cm; slightly decomposed plant material; many fine and common medium and coarse roots; abrupt smooth boundary

A--5 to 14 cm; medial silt loam, brown (7.5YR 5/2) dry, dark brown (7.5YR 3/2) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; weakly smeary; few medium and coarse and common very fine roots; many fine irregular pores; strongly acid (pH 5.2); abrupt wavy boundary

AB--14 to 37 cm; medial silt loam, brown (7.5YR 5/3) dry, dark brown (7.5YR 3/3) moist; moderate very fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; weakly smeary; few very fine and medium and common coarse roots; common fine and very fine tubular pores; strongly acid (pH 5.4); abrupt wavy boundary

Bw--37 to 59 cm; medial silt loam, brown (7.5YR 5/4) dry, brown (7.5YR 4/4) moist; moderate very fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; weakly smeary; common coarse and few very fine roots; common fine and very fine tubular pores; strongly acid (pH 5.4); clear wavy boundary

Bg1--59 to 107 cm; medial silty clay loam, light yellowish brown (10YR 6/4) dry, brown (7.5YR 4/4) moist; moderate very fine subangular blocky structure; slightly hard, very friable, slightly sticky and moderately plastic; weakly smeary; few very fine roots; common fine and very fine tubular pores; 5 percent medium distinct masses of oxidized iron throughout, yellowish red (5YR 5/6) moist, and 5 percent medium prominent iron depletions throughout, gray (7.5YR 6/1) moist; strongly acid (pH 5.5); clear wavy boundary

Bg2--107 to 150 cm; silty clay loam, very pale brown (10YR 7/3) dry, pale brown (10YR 6/3) moist; massive; hard, firm, moderately sticky and moderately plastic; few very fine roots; nonsmeary; common fine and very fine tubular pores; 10 percent fine and 10 percent medium prominent irregular masses of oxidized iron with clear boundaries in matrix, strong brown (7.5YR 5/8) moist, and 10 percent fine and 10 percent medium prominent irregular masses of reduced iron with clear boundaries in matrix, light olive brown (2.5Y 5/6) moist; strongly acid (pH 5.5)

TYPE LOCATION: Pacific County, Washington, about 13 km southwest of South Bend, along U.S. Highway 101, at the intersection of Bone River C-Line and C-100 spur; in the NW1/4SE1/4 of section 4, T. 13 N., R. 10 W., Willamette Meridian; latitude 46.6417140 degrees north, longitude -123.9281140 degrees west, WGS 84 (GPS coordinates)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--8 to 10 degrees C
Depth to redoximorphic features--50 to 100 cm below the mineral soil surface

Control section
*Rock fragment content--0 to 10 percent
*Bulk density--0.70 to 0.90 g/cm3
*Ammonium oxalate extractable aluminum plus one-half iron--2 to 5 percent
*Phosphate retention--85 to 100 percent

Oi horizon
*Thickness--3 to 6 cm

A horizon
*Hue--7.5YR, 10YR
*Value--4 or 5 dry
*Chroma--2 or 3 moist, 3 or 4 dry
*Clay content--15 to 25 percent (field estimate)
*Organic matter content--10 to 20 percent
*Reaction--4.5 to 6.0
*Thickness--5 to 15 cm

AB horizon
*Hue--5YR to 10YR
*Value--2 to 3 moist, 3 to 5 dry
*Chroma--2 or 3 moist, 3 to 6 dry
*Organic matter--4 to 7 percent
*Clay content--25 to 35 percent (field estimate)
*Fine-earth texture--medial silt loam, medial silty clay loam
*Reaction--4.5 to 6.0
*Thickness--15 to 25 cm

Bw horizon
*Hue--5YR to 10YR
*Value--3 or 4 moist, 3 to 5 dry
*Chroma--2 or 3 moist, 3 to 6 dry
*Organic matter content--4 to 7 percent
*Clay content--25 to 35 percent (field estimate)
*Fine-earth texture--medial silt loam, medial silty clay loam
*Reaction--4.5 to 6.0
*Thickness--15 to 30 cm

Bg1 horizon
*Hue--7.5YR to 2.5Y
*Value--3 to 5 moist, 4 to 6 dry
*Chroma--2 to 4 moist, 3 to 6 dry
*Organic matter content--0 to 1 percent
*Clay content--25 to 35 percent (field estimate)
*Fine-earth texture--medial silt loam, medial silty clay loam
*Reaction--4.5 to 6.0

Bg2 horizon
*Hue--10YR to 5Y
*Value--4 to 6 moist, 5 to 7 dry
*Chroma--2 to 4 moist, 3 to 6 dry
*Organic matter content--0 to 1 percent
*Clay content--25 to 35 percent (field estimate)
*Fine-earth texture--silt loam, silty clay loam
*Reaction--4.5 to 6.0

COMPETING SERIES:
Lagitos--paralithic contact 50 to 100 cm from the soil surface
Ozette--densic contact 100 to 150 cm from the soil surface

GEOGRAPHIC SETTING:
Elevation--0 to 185 m
Climate--marine; cool, moist summers; cool, wet winters
Mean annual precipitation--2000 to 3300 mm
Mean annual air temperature--7 to 9 degrees C
Frost free period--160 to 220 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Calawah--no aquic conditions; on similar landforms
Ilwaco, Lebam, Vesta--no aquic conditions; on nearby mountains and hills
Palix--no aquic conditions; paralithic contact 100 to 150 cm from the soil surface; on adjacent hills
Narel--no aquic conditions; lithic contact 100 cm from the soil surface; on nearby mountain slopes

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--moderately well drained
Saturation in normal years--saturated below a depth of 50 cm in November through April and below a depth of 100 cm in May through October
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--high or moderately high above Bg2 horizon, moderately low in Bg2 horizon

USE AND VEGETATION:
Use--wildlife habitat, recreation, timber production, homesite development
Potential natural vegetation--Sitka spruce, western hemlock, vine maple, evergreen huckleberry, red huckleberry, western swordfern, salal, salmonberry

DISTRIBUTION AND EXTENT: Olympic Peninsula coast, Washington; MLRA 4; moderate extent

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

SERIES ESTABLISHED: Soil Survey of Grays Harbor County Area, Pacific County, Washington; 1978

REMARKS:
Diagnostic horizons and other features in this pedon
*Umbric epipedon--zone from 5 to 37 cm
*Cambic horizon--zone from 37 to 150 cm
*Particle-size control section--zone from 5 to 105 cm
*Andic soil properties--zone from 5 to 105 cm
*Aquic conditions--zone from 59 to 150 cm
*Redoximorphic iron concentrations--zone from 59 to 150 cm
*Redoximorphic iron depletions with chroma of 2 or less--zone from 59 to 150 cm

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National Cooperative Soil Survey
U.S.A.