LOCATION WHIDBEY            WA
Established Series
Rev. MPR/EED/SBC
07/2007

WHIDBEY SERIES


The Whidbey series consists of moderately deep to densic contact, moderately well drained soils formed in glacial drift overlying dense glaciomarine deposits. Whidbey soils are on hillslopes of glacial drift plains at elevations 0 to 90 meters. Slopes are 0 to 45 percent. Mean annual precipitation is about 610 mm. Mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Aquic Dystroxerepts

TYPICAL PEDON: Whidbey gravelly loam, forested, on a northwest facing sideslope at 76 meters elevation. When described on August 16, 2005 the soil was dry throughout. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 5 cm; slightly decomposed plant material; abrupt smooth boundary.

A--5 to 15 cm; brown (10YR 5/3) gravelly loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine, many fine, and few medium and coarse roots; many very fine and fine irregular pores; 15 percent gravel and 10 percent cobbles; moderately acid (pH 5.7); clear wavy boundary. (5 to 20 cm thick)

Bw--15 to 51 cm; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine, fine, and medium and few coarse roots; common very fine and fine interstitial and irregular pores; 45 percent gravel and 5 percent cobbles; moderately acid (pH 5.7); clear wavy boundary. (25 to 60 cm thick)

Bg--51 to 94 cm; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 5/3) moist; moderate fine subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; few very fine and fine roots between peds; common very fine and fine interstitial and irregular pores; common distinct weakly cemented light gray (10YR7/2), light brownish gray (10YR 6/2) moist, iron depletions in matrix; many distinct weakly cemented brownish yellow (10YR6/6), yellowish brown (10YR 5/6) moist, iron-manganese masses in matrix; 45 percent gravel and 5 percent cobbles; slightly acid (pH 6.2); abrupt wavy boundary. (10 to 40 cm thick)

2Cd--94 to 152 cm; light olive brown (2.5Y 5/3) gravelly sandy loam, olive brown (2.5Y 4/3) moist; massive; hard, firm, nonsticky, nonplastic; few very fine irregular pores; common distinct weakly cemented brownish yellow (10YR6/6), yellowish brown (10YR 5/6) moist, iron-manganese masses in matrix; common distinct weakly cemented light gray (10YR7/2), light brownish gray (10YR 6/2) moist, iron depletions in matrix; 25 percent gravel; neutral (pH 6.9).

TYPE LOCATION: San Juan County, Washington; Section 23, T.35N., R.2W. Willamette Meridian; USGS Shaw Island, Washington quadrangle; lat. 48 degrees 30 minutes 49 seconds N. and long. 122 degrees 54 minutes 6 seconds W.

RANGE IN CHARACTERISTICS: Depths to diagnostic horizons and features start from the mineral soil surface.
Mean annual soil temperature - 10 to 11 degrees C
Depth to redoximorphic features - 46 to 75 cm
Depth to densic contact - 50 to 100 cm
Reaction - moderately acid to neutral
Particle-size control section:
Clay content - 4 to 18 percent
Rock fragments - 35 to 70 percent gravel and 0 to 20 percent cobbles

A horizon
Hue - 10YR or 7.5YR
Value - 2 or 3 moist, 4 or 5 dry
Chroma - 2 or 3 moist and dry
Rock fragments - 0 to 15 percent

Bw horizon
Hue 10YR, 7.5YR or 2.5Y
Value - 3 to 5 moist, 4 to 6 dry
Chroma - 3 or 4 moist and dry
Texture - L, SL, COSL
Clay content - 4 to 15 percent
Rock fragments - 35 to 70 percent gravel and 0 to 20 percent cobbles

Bg horizon
Hue 10YR or 2.5Y
Value - 4 or 5 moist, 5 or 6 dry
Chroma - 3 or 4 moist and dry
Texture - SL, LS
Clay content - 5 to 18 percent
Rock fragments - 35 to 70 percent gravel 0 to 10 percent cobbles

Cd horizon
Hue 10YR, 2.5Y or 5Y
Value - 4 to 6 moist, 5 to 7 dry
Chroma - 2 or 3 moist and dry
Texture - SL, SCL, COSL
Clay content - 9 to 24 percent
Rock fragments - 10 to 50 percent gravel and 0 to 10 percent cobbles

COMPETING SERIES: There are no competing series in this family.

GEOGRAPHIC SETTING: Whidbey soils are on hillslopes of glacial drift plains. Slopes range from 0 to 45 percent. These soils are formed in glacial drift overlying dense glaciomarine deposits. Elevations are from 0 to about 100 meters. These soils occur in a mild marine climate with warm dry summers and mild wet winters. Mean annual precipitation is about 457 to 762 mm, most of which falls as rain in the late fall, winter and early spring. Mean annual temperature is about 9 degrees C. The frost-free period is about 200-240 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hoypus, Keystone, and Sholander soils. Keystone soils are found on glacial outwash plains, kames, kettles, and moraines. Keystone soils do not have a densic contact or redoximorphic features above 150 cm. Sholander, and Hoypus soils are on similar landscape positions. Sholander soils are sandy and have redoximorphic features at 20 to 46 cm. Hoypus soils do not have a densic contact or redoximorphic features above 150 cm.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained. Saturated hydraulic conductivity is high to very high in the Bw and Bg horizons, and very low in the Cd horizon. Whidbey soils have a perched water table as high as 46 cm during January, February, November, and December.

USE AND VEGETATION: Whidbey soils are used for timber production, wildlife habitat, forage crop production, and livestock grazing. Potential natural vegetation is Douglas-fir, madrone, lodgepole pine, oceanspray, baldhip rose, salal, Cascade Oregongrape, rattlesnake plantain, and bracken fern.

DISTRIBUTION AND EXTENT: Northwestern Washington. Series is of moderate extent.

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

SERIES ESTABLISHED: Island County, Washington, 1950.

REMARKS: Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon
Cambic horizon - the zone from 15 to 51 cm,
Densic contact - 94 cm. (upper boundary of Cd horizon)
Particle-size control section - 25 to 94 cm (to the Cd horizon)
Depth to redoximorphic features with chroma of 2 or less - 51 cm
This revision (6/2006) includes a new type location. The classification has not changed. The new typical pedon does not have an albic horizon.


National Cooperative Soil Survey
U.S.A.