LOCATION CHUCKANUT               WA

Established Series
Rev. RDM/CAB/KMS
03/2013

CHUCKANUT SERIES


The Chuckanut series consists of deep and very deep, well drained soils formed in volcanic ash and colluvium from sandstone over glacial till. These soils are on hills and mountain slopes and have slopes ranging from 5 to 65 percent. Mean annual air temperature is about 9 degrees C, and average annual precipitation is about 1015 mm.

TAXONOMIC CLASS: Coarse-loamy, isotic, mesic Andic Dystroxerepts

TYPICAL PEDON: Chuckanut gravelly ashy sandy loam - on a 15 percent convex southeast facing slope under a coniferous canopy of Douglas-fir. (Colors are for moist soil unless otherwise stated. All textures are apparent field textures.)

Oi--0 to 13 cm; undecomposed needles, twigs, and leaves.

Oe--13 to 18 cm; partially decomposed forest litter.

E--18 to 23 cm; brown (7.5YR 4/2) gravelly ashy sandy loam, pinkish gray (7.5YR 7/2) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots, many very fine irregular pores; 20 percent gravel; strongly acid (pH 5.4); abrupt wavy boundary. (0 to 8 cm thick)

Bw1--23 to 41 cm; dark yellowish brown (10YR 4/6) gravelly ashy loam, brownish yellow (10YR 6/6)
dry; weak fine subangular blocky structure parting to weak medium granular; slightly hard, very friable, slightly sticky, slightly plastic and weakly smeary; common very fine roots; common medium irregular pores; 25 percent gravel and 20 percent paragravel; NaF pH 11.5; moderately acid acid (pH 5.6); clear wavy boundary. (18 to 25 cm thick)

Bw2--41 to 56 cm; dark yellowish brown (10YR 4/4) gravelly ashy loam, light yellowish brown (10YR 6/4) dry; weak fine subangular blocky structure parting to weak medium granular; slightly hard, very friable, slightly sticky, slightly plastic and weakly smeary; few coarse and common fine roots; common medium irregular pores; 25 percent gravel, 25 percent paragravel; NaF pH 11.5; moderately acid (pH 5.8); clear wavy boundary. (13 to 23 cm thick)

BC--56 to 107 cm; olive brown (2.5Y 4/4) gravelly sandy loam, pale yellow (2.5Y 8/4) dry; weak coarse subangular blocky structure; soft, friable, nonsticky and nonplastic; very few fine roots; few medium irregular pores; 20 percent gravel and 30 percent paragravel; NaF pH 10.0; moderately acid (pH 5.6); gradual wavy boundary. (46 to 64 cm thick)

2C--107 to 142 cm; olive brown (2.5Y 4/4) gravelly loam, pale yellow (2.5Y 7/4) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; very few very fine roots; common very fine irregular pores; 20 percent gravel and 25 percent paragravel; NaF pH 9.0; strongly acid (pH 5.4); abrupt smooth boundary. (0 to 51 cm thick)

2Cr--142 cm; paralithic contact with sandstone.

TYPE LOCATION: Skagit County, Washington; 1.6 kilometers south of Devils Lake; 730 meters south and 91 meters east of the northwest corner, sec. 14, T. 33 N., R. 4 E. Willamette Meridian; Latitude: 48.349056, Longitude: -122.268623, Datum: WGS84.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 8 to 11 degrees C; Mesic soil temperature regime
Moisture control section: dry for 60 to 75 consecutive days from June to October. Xeric soil moisture regime
Depth to a paralithic contact: greater than 100 cm
Particle size control section: 0 to 35 percent fragments, 5 to 15 percent clay
Reaction: moderately acid or strongly acid throughout
Volcanic ash influence: 18 to 30 cm thick
Properties of volcanic ash influenced layers:
Bulk density: less than or equal to 1.0 g/cm3
Al + Fe: greater than 1.0 %
Volcanic glass content: greater than 5 %



A horizon (present in some pedons)
Value - 2 through 4, moist or dry
Chroma - 2 or 3, moist or dry
Fine earth texture - ashy loam or ashy sandy loam
Rock Fragments - 0 to 15 percent gravel and 0 to 5 percent cobbles

E horizon
Hue - 7.5YR or 10YR
Value - 2 through 4 moist, 4 through 7 dry
Chroma - 2 or 3 moist and 2 through 4 dry
Thickness - 0 to 5 cm
Fine earth texture - ashy sandy loam or ashy loam
Rock Fragments - 0 to 20 percent gravel, 0 to 5 percent cobbles, and 0 to 25 percent total
Paragravels - 0 to 15 percent

Bw horizons
Hue - 7.5YR or 10YR
Value - 3 through 6 moist, 5 through 7 dry
Chroma - 3 through 6, moist or dry
Texture - ashy loam or ashy sandy loam
Rock Fragments - 0 to 25 percent gravel, 0 to 5 percent cobbles, and 0 to 30 percent total
Paragravels - 10 to 45 percent

BC horizon
Hue - 2.5Y or 10YR
Value - 2 through 4 moist, 5 through 7 dry
Chroma - 3 through 5, moist or dry.
Fine earth texture - loam or sandy loam.
Rock Fragments - 0 to 30 percent gravel, 0 to 5 percent cobbles, and 0 to 35 percent total
Paragravels - 10 to 45 percent

2C horizon
Hue - 10YR or 2.5Y
Value - 4 through 7 moist, 6 through dry
Chroma - 2 through 6, moist or dry
Fine earth texture - loam or sandy loam
Rock Fragments - 10 to 30 percent gravel, 0 to 5 percent cobbles, and 10 to 35 percent total
Paragravel - 20 to 50 percent

COMPETING SERIES: These are the Constitution, Kapowsin, Menzel, Sadie, and Skipjack series. Constitution is moderately deep to bedrock. Kapowsin soils formed in dense glacial till, have redoximorphic features within 100 cm, and are 50 to 100 cm deep to a pan cemented with aluminum, iron, and organic matter. Menzel soils are dry less than 45 days. Sadie soils have a densic contact at 65 to 100 cm and have redoximorphic features within 100 cm. Skipjack soils are greater than 150 cm to a lithic contact.

GEOGRAPHIC SETTING: Chuckanut soils are on hillslopes and mountain slopes with slopes of 5 to 65 percent. Elevation ranges from 100 to 600 meters. The soils formed in volcanic ash and colluvium from sandstone and glacial till. Chuckanut soils have a marine climate with dry, warm summers and cool, moist winters with intermittent snow cover. The mean annual air temperature ranges from 8 to 10 degrees C, and the average annual precipitation is 890 to 1150 mm. The frost-free season is 160 to 200 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barneston, Cathcart, Ovall, Skipopa, Squires, and Tokul. Barneston soils are sandy- skeletal. Cathcart does not have contrasting particle size classes. Ovall and Squires soils are moderately deep to a lithic contact. Skipopa soils are clayey and have an argillic horizon. Tokul soils are moderately deep to ortstein.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. Moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Used primarily for woodland. Native vegetation includes Douglas-fir, western hemlock, western redcedar, and red alder, with an undergrowth of salal, western brackenfern, western swordfern, Oregon-grape, red huckleberry, deer fern, princes pine, bedstraw, and Pacific trillium.

DISTRIBUTION AND EXTENT: Northwestern Washington. These soils are moderately extensive.

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

SERIES ESTABLISHED: Skagit County, Washington, 1980.

REMARKS:
Diagnostic horizons and features include:
Albic Horizon - 18 to 23 cm
Andic soil properties - 18 to 56 cm (assumed to meet criteria 3 for andic soil properties)
Cambic Horizon - 23 to 107 cm
Folistic Epipedon - 0 to 18 cm
Lithologic discontinuity - 107 cm
Paraltihic conrtact - 142 cm
Particle Size Control Section - 43 to 142 cm

12/2012 - This OSD was updated in 2012 as part of a SDJR project. At that time, Chuckanut was classified as an Ashy over loamy, amorphic over istoic, mesic Typic Vitrixerands. There was no strong evidence to support this classification, therefore it was changed to an updated version of its original classification and concept. It is recommended that samples are collected for analysis to verify the presence or absence of andic and spodic soil properties.

4/94 - Classification was changed to Ashy over loamy, amorphic over isotic, mesic Typic Vitrixerands from medial, mesic Andic Xerocherpet
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National Cooperative Soil Survey
U.S.A.