LOCATION CALDWELL WA+ID
Established Series
Rev. SMM/RWL/SHB/SBC
06/2016
CALDWELL SERIES
Landscape--Columbia basalt plateau
Landform--flood plains, drainageways
Slope--0 to 3 percent
Parent material--fine-silty alluvium derived dominantly from loess with a slight influence of volcanic ash in some areas
Mean annual precipitation--about 50 cm
Mean annual air temperature--about 9 degrees C
Depth class--very deep
Drainage class--somewhat poorly drained
Soil moisture regime--xeric
Soil temperature regime--mesic
Soil moisture subclass--oxyaquic
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Cumulic Haploxerolls
TYPICAL PEDON: Caldwell silt loam, cultivated
Ap--0 to 23 centimeters; silt loam, grayish brown (10YR 5/2) dry, very dark gray (10YR 3/1) moist; weak thick platy structure parting to weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; many roots, common fine tubular pores; neutral (pH 6.8); abrupt smooth boundary
A--23 to 43 centimeters; silt loam, dark gray (10YR 4/1) dry, black (10YR 2/1) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, friable, moderately sticky and slightly plastic; common roots; common fine tubular pores; common organic staining; neutral (pH 7.2); clear smooth boundary
ABt--43 to 66 centimeters; silt loam, dark gray (10YR 4/1) dry, very dark gray (10YR 3/1) moist; moderate medium prismatic structure parting to moderate medium angular blocky; hard, slightly firm, moderately sticky and moderately plastic; common roots; many fine tubular pores; few faint patchy clay films on faces of peds; few distinct organic stains on faces of peds; few faint silica coatings on vertical faces of peds; neutral (pH 7.2); clear smooth boundary
Btg1--66 to 99 centimeters; silty clay loam, gray (10YR 5/1) dry, very dark gray (10YR 3/1) moist; moderate medium prismatic structure parting to moderate medium angular blocky; hard, firm, moderately sticky and moderately plastic; common roots; common fine tubular pores; few faint patchy clay films on faces of peds; few distinct silica coatings on faces of peds; neutral (pH 7.2); abrupt smooth boundary
Btg2--99 to 137 centimeters; silty clay loam, light brownish gray (2.5Y 6/2) dry, very dark grayish brown (2.5Y 3/2) moist; massive; hard, firm, moderately sticky and moderately plastic; few roots; few fine tubular pores; few faint clay films on faces of peds; many fine prominent masses of iron accumulation that are yellowish brown (10YR 5/6) moist and have clear boundaries and few fine prominent masses of iron accumulation that are brown (7.5YR 4/4) moist and have sharp boundaries in matrix; neutral (pH 7.2); abrupt smooth boundary
Cg--137 to 155 centimeters; silty clay loam, light brownish gray (2.5Y 6/2) dry, dark grayish brown (2.5Y 4/2) moist; massive; hard, firm, moderately sticky and moderately plastic; no roots; few fine tubular pores; common fine masses of iron accumulation throughout; neutral (pH 7.0)
TYPE LOCATION: Whitman County, Washington, about 120 m west and 60 m north of the southeast corner of section 15, T. 15 N., R. 45 E.; Viola ID, Washington, U.S. Geological Survey topographic quadrangle; latitude 46.7792100, longitude -117.1187000, datum WGS 84 (coordinates estimated from PLSS data)
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon--50 to 95 cm; may include part of Btg horizon
Depth to aquic conditions with chroma of 2 or less and redoximorphic concentrations--75 to 100 centimeters
Mean annual soil temperature at a depth of 50 centimeters--9 to 10 degrees C
Moisture control section--saturated during certain seasons of year, but dry 45 to 60 consecutive days following summer solstice in all parts between depths of 10 and 30 cm in most years
Volcanic ash content--small pockets in lower part of some profiles
Ap, A, and ABt horizons
Value--3 to 5 dry, 1 to 3 moist
Chroma--1 to 3 moist or dry
Content of clay--15 to 27 percent
Reaction--6.1 to 7.8
Thickness of Ap horizon--15 to 25 cm
Thickness of A horizon--18 to 23 cm
Thickness of ABt horizon--15 to 25 cm
Btg horizon, or Bt horizon (where present)
Hue--10YR, 2.5Y
Value--4 to 6 dry, 2 to 5 moist
Chroma--1 to 4 moist or dry
Texture--silt loam, silty clay loam
Structure--prismatic
Redoximorphic features--faint to distinct; hue of 5YR to 10YR
Clay films--faint to distinct; discontinuous; on vertical faces of some peds
Content of clay--18 to 35 percent
Reaction--6.6 to 7.8
Combined thickness--60 to 110 cm
Cg horizon (where present)
Hue--10YR, 2.5Y
Value--4 to 7 dry, 2 to 4 moist
Chroma--1 to 4 moist or dry
Texture--silt loam, silty clay loam
Content of rock fragments--0 to 5 percent basalt gravel
Content of clay--18 to 35 percent
Reaction--6.6 to 7.8
COMPETING SERIES:
Harana--strongly alkaline in A horizon; dry more than 60 consecutive days
Jett,
Keigley--calcareous; no aquic conditions within a depth of 100 cm
Loupence,
Rustico--aridic soil moisture regime
Red Rock--calcareous in C horizon; no aquic conditions within a depth of 100 cm
Snow--no aquic conditions with redoximorphic features that have chroma of 2 or less within a depth of 100 cm
GEOGRAPHIC SETTING:
Elevation--520 to 810 m
Climate--warm, dry summers; cool, moist winters
Mean annual precipitation--430 to 610 mm
Mean annual air temperature--7 to 10 degrees C
Frost-free period--about 90 to 140 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Konert--fine-textured argillic horizon; on flood plains
Latah--albic horizon; fine-textured argillic horizon; on low terraces and in drainageways
Naff,
Palouse,
Thatuna--no redoximorphic depletions or reduced matrix with chroma of 2 or less; on loess hills adjacent to drainageways
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat poorly drained
Saturated hydraulic conductivity (Ksat)--moderately high
Apparent seasonal high water table--uppermost limit in January through June
USE AND VEGETATION:
Use--dominantly crop production
Common crops--small grain, peas, lentils, legumes, grass hay, pasture crops
Native vegetation--basin wildrye, tufted hairgrass, sedge, bluebunch wheatgrass, redtop, hawthorn
DISTRIBUTION AND EXTENT: Southeastern Washington and western Idaho; MLRA 9; moderate extent
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Boise Area, Idaho; 1901
REMARKS:
Diagnostic horizons and other features in this pedon
*Mollic epipedon--zone from surface to a depth of 99 cm
*Cumulic feature--zone from surface to a depth of 80 cm; assumed irregular decrease in organic carbon content as depth increases
*Cambic horizon--zone from 99 to 137 cm; evidence of oriented clay but does not meet required criteria for clay increase
*Oxyaquic feature--saturated zone from 75 to 100 cm; aquic conditions; chroma of 2 or less with redoximorphic concentrations
*Particle-size control section--zone from 25 to 100 cm
1/22/2015--The official series description was updated as part of a soil data join recorrelation project. The updates include the following--
*Lowered reaction class by one class (moderately alkaline to slightly alkaline) for lower part of subsoil and for substratum in range in characteristics.
*Revised vegetation to include plants associated with LOAMY BOTTOM (R009XY402WA) ecological site.
*Revised "Geographic Setting" paragraph.
Further MLRA-wide investigation needed to--
*Determine degree and extent of influence of volcanic ash from Mount St. Helens, Glacier Peak, and Mount Mazama in loessal alluvium.
*Document depth and duration of apparent water table related to current ecological site assignment; original concept from 1975 for WET MEADOW ecological site that included rushes and cattails.
*Evaluate and document condition for higher reaction class (moderately alkaline) in range in characteristics for lower part of subsoil and in substratum in original 1975 concept.
6/2016--This official series description was updated as part of the final correlation of the Spokane County, Washington, soil survey. The formatting was updated according to SSR1 Technical Note 11--Content and Format of Official Series Descriptions (revised 12/2015).
National Cooperative Soil Survey
U.S.A.