LOCATION SEABOLDT                WA

Established Series
IRD. KMS/SHB/SBC
12/2022

SEABOLDT SERIES

Landscape--channeled scablands
Landform--outwash plains on plateaus
Slope--0 to 15 percent
Parent material--loess mixed with a minor amount of volcanic ash over glaciofluvial deposits over residuum derived from basalt
Mean annual precipitation--about 510 mm
Mean annual air temperature--about 9 degrees C
Depth class--moderately deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--mesic
Soil moisture subclass--typic

TAXONOMIC CLASS: Coarse-loamy, isotic, mesic Vitrandic Haploxerolls

TYPICAL PEDON: Seaboldt ashy loam in a historically farmed field that is returning to native vegetation, on a north-facing, 4-percent slope at an elevation of 730 m (When described on August 8, 2000, the soil was dry throughout. All textures are apparent field textures.)

Ap1--0 to 18 cm; ashy loam, brown (10YR 5/3) dry, very dark grayish brown (10YR 3/2) moist; moderate very thick platy structure parting to moderate medium subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine to coarse roots throughout; common very fine irregular pores and common very fine and fine tubular pores; 1 percent subrounded basalt gravel; slightly acid (pH 6.5); clear smooth boundary

Ap2--18 to 25 cm; ashy loam, brown (10YR 4/3) dry, very dark grayish brown (10YR 3/2) moist; moderate very thick subangular blocky structure parting to moderate coarse subangular blocky; moderately hard, friable, slightly sticky and slightly plastic; common very fine roots throughout; common very fine and fine tubular pores and common very fine irregular pores; 1 percent subrounded basalt gravel; slightly acid (pH 6.5); abrupt smooth boundary

Bw1--25 to 41 cm; loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; moderate coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few fine to medium and common very fine roots throughout; common very fine to medium tubular pores and common very fine irregular pores; 1 percent subrounded basalt gravel; slightly acid (pH 6.3); clear smooth boundary

2Bw2--41 to 58 cm; sandy loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; weak coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and few fine to coarse roots throughout; few fine tubular pores and common very fine and fine irregular pores; 8 percent subangular basalt gravel and 3 percent angular basalt cobbles; slightly acid (pH 6.5); abrupt wavy boundary

2C--58 to 71 cm; extremely gravelly sandy loam, yellowish brown (10YR 5/4) dry, dark yellowish brown (10YR 3/4) moist; single grain; soft, loose, nonsticky and nonplastic; few fine and medium and common very fine roots throughout; common very fine and fine irregular pores; 70 percent subangular basalt gravel; slightly acid (pH 6.5); abrupt wavy boundary

3R--71 cm; indurated basalt; fractures at intervals of 10 to 45 cm

TYPE LOCATION: Spokane County, Washington, about 5 km northeast of Marshall; about 90 m west and 380 m north of the southeast corner of section 13, T. 24 N., R. 42 E.; Spokane SW, Washington, U.S. Geological Survey topographic quadrangle; latitude 47.5688400, longitude -117.4331131, datum WGS 84 (coordinates measured with GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--9 to 11 degrees C
Moisture control section--dry 60 to 90 consecutive days after summer solstice (July through September); moist in October through June
Depth to basalt--50 to 100 cm
Thickness of mollic epipedon--25 to 50 cm
Base saturation--less than 75 percent, by sum of cations, in one or more horizons between depths of 25 and 75 cm (estimated)
Particle-size control section--averages 4 to 18 percent clay and 0 to 25 percent rock fragments
Thickness of layers influenced by volcanic ash--18 to 35 cm

Estimated properties of layers influenced by volcanic ash
*Content of volcanic glass in 0.02- to 2-mm fraction--5 to 20 percent
*Ammonium oxalate Al plus 1/2 Fe--0.4 to 1.0 percent

An Oi horizon is in uncultivated areas.

Ap horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Texture--ashy loam, ashy silt loam
Content of clay--8 to 22 percent
Content of gravel--0 to 10 percent
Reaction--6.1 to 7.3
Combined thickness--20 to 50 cm

Bw and 2Bw horizons
Value--4 or 5 dry, 2 or 3 moist
Chroma--3 or 4 dry or moist
Texture--loam, sandy loam, silt loam
Content of clay--4 to 18 percent
Content of gravel--0 to 25 percent
Content of cobbles--0 to 10 percent
Total content of rock fragments--0 to 30 percent
Reaction--6.1 to 7.3
Combined thickness of Bw and 2Bw horizons--30 to 76 cm

2C horizon (where present)
Value--5 or 6 dry, 3 or 4 moist
Chroma--4 to 6 dry or moist
Texture--loamy sand, sand, sandy loam
Content of clay--2 to 10 percent
Content of gravel--10 to 70 percent
Content of cobbles--0 to 15 percent
Content of stones--0 to 5 percent
Total content of rock fragments--15 to 75 percent
Reaction--6.1 to 7.3
Thickness--0 to 25 centimeters

Lamellae are in some pedons.

COMPETING SERIES:
Donavan--moderately deep to dense glacial till
Fourmound--deep to lithic contact with basalt; on mima mounds; formed in loess and volcanic ash
Goldlake--formed in glacial till; very deep
Moneycreek--very deep to basalt
Spokane, Usk--moderately deep to paralithic contact with granitic rock

GEOGRAPHIC SETTING:
Elevation--550 to 775 m
Climate--warm, relatively dry summers; cool, moist winters
Mean annual precipitation--405 to 635 mm
Mean annual air temperature--6 to 11 degrees C
Frost-free season--90 to 150 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Battleplain--sandy; very deep; on outwash plains
Clayton--very deep; on outwash plains
Hagen, Marble--sandy; very deep; on outwash plains
Fourmound--deep; on basalt plateaus
Northstar--loamy-skeletal; on basalt plateaus
Phoebe--very deep; on outwash plains

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately high

USE AND VEGETATION:
Use--dominantly homesite development and crop production; wildlife habitat in some areas
Common crops--small grain, hay, pasture
Potential natural vegetation--ponderosa pine, Saskatoon serviceberry, common snowberry, Idaho fescue, arrowleaf balsamroot, bluebunch wheatgrass, common yarrow, lupine

A dry phase of the Seaboldt series is mapped in Spokane County and is correlated to ecological site R009XY102WA.

DISTRIBUTION AND EXTENT: Eastern Washington; MLRAs 9 and 44A; small extent

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

SERIES ESTABLISHED: Spokane County, Washington; 2012; name from nearby road

REMARKS:
Diagnostic horizons and other features in this pedon
*Mollic epipedon--zone from 0 to 25 cm
*Cambic horizon--zone from 25 to 58 cm
*Vitrandic feature--zone from 0 to 25 cm
*Ultic feature--zone from 25 to 71 cm; base saturation (sum) of less than 75 percent
*Depth to lithic contact--71 cm
*Particle-size control section--zone from 25 to 71 cm

This series is correlated to the ponderosa pine/common snowberry (PIPO/SYAL) habitat type (Cooper, Stephen V.; Kenneth E. Neiman; and David W. Roberts. 1991. Forest habitat types of northern Idaho: a second approximation. General Technical Report INT-236. U.S. Department of Agriculture, Forest Service, Intermountain Research Station.)

6/2016--This official series description was updated as part of the final correlation of the Spokane County, Washington, soil survey. The series describes the soils formerly mapped as Gibbs taxadjunct. The primary taxadjunct feature is the coarse-loamy particle-size control section that is dominantly coarser glaciofluvial parent material. The formatting was updated according to SSR1 Technical Note 11--Content and Format of Official Series Descriptions (revised 12/2015).

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National Cooperative Soil Survey
U.S.A.