LOCATION PHOEBE                  WA+UT

Established Series
Rev. DWB/SHB/EMM
02/2011

PHOEBE SERIES

The Phoebe series consists of very deep, well drained soil formed in glacial outwash mixed with volcanic ash and loess in the upper part. Phoebe soils are on outwash terraces and have slopes of 0 to 65 percent. The mean annual precipitation is about 18 inches, and the mean annual temperature is about 48 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Vitrandic Haploxerolls

TYPICAL PEDON: Phoebe ashy sandy loam - cultivated. (Colors are for dry soils unless otherwise noted. All textures are apparent field textures.)

Ap--0 to 8 inches; dark gray (10YR 4/1) ashy sandy loam, black (10YR 2/1) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; few fine tubular and irregular pores; slightly acid (pH 6.2); abrupt smooth boundary. (6 to 10 inches thick)

A--8 to 16 inches; dark grayish brown (10YR 4/2) ashy sandy loam, very dark brown (10YR 2/2) moist; weak medium granular structure; soft, very friable, slightly sticky and slightly plastic; many fine roots; many fine irregular pores; slightly acid (pH 6.4); clear wavy boundary. (6 to 10 inches thick)

Bw1--16 to 25 inches; brown (10YR 5/3) fine sandy loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common fine roots; many fine irregular pores; neutral (pH 6.6); gradual wavy boundary. (8 to 20 inches thick)

Bw2--25 to 34 inches; light yellowish brown (10YR 6/4) sandy loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common fine roots; many fine irregular pores; neutral (pH 6.6); gradual wavy boundary. (0 to 20 inches thick)

C1--34 to 44 inches; light yellowish brown (10YR 6/4) loamy sand, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine roots; common fine interstitial pores; neutral (pH 6.6); gradual wavy boundary. (8 to 12 inches thick)

C2--44 to 60 inches; very pale brown (10YR 7/4) sand, yellowish brown (10YR 5/4) moist; single grain; loose; few fine roots; common fine interstitial pores; neutral (pH 6.6)

TYPE LOCATION: Spokane County, Washington; about 3.5 miles northwest of Colbert, WA., 260 feet south of highway station 521 and 120 feet west of center of primary state highway #3 ; about 2,500 feet east and 1,050 feet north of the southwest corner of section 7, T. 27 N., R. 43 E. USGS Dartford, Wa. Topographic quadrangle; (Latitude 47 degrees, 50 minutes, 54 seconds N. and Longitude 117 degrees, 25 minutes, 20 seconds W.), NAD83

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 47 to 52 degrees F.
Soil moisture - usually moist, but are dry 60 to 90 consecutive days during the summer and fall.
Depth to loamy sand or sand - 30 to 60 inches
Mollic epipedon - 20 to 32 inches thick
Volcanic ash influence - 12 to 20 inches
Estimated properties of the volcanic ash influenced layer:
Volcanic glass content - 5 to 20 percent
Acid oxalate extractable aluminum + Fe- 0.4 to 1.0 percent
15-bar water retention - 5 to 12 percent (air-dried)
Moist bulk density 1.15 to 1.35 g/cc
Particle-size control section - averages 0 to 15 percent coarse fragments and 5 to 15 percent clay
Soil reaction - slightly acid or neutral
Base saturation - assumed to be less than 75 percent (by sum) in one or more horizons between 10 and 30 inches.

A horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 1 to 3, dry or moist
Texture fine sandy loam, sandy loam
Gravel content 0 to 5 percent

Bw1 horizon
Hue - 10YR or 7.5YR
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 to 4, dry or moist
Texture fine sandy loam, sandy loam
Gravel content 0 to 10 percent

Bw2 horizon (BC horizon when present)
Hue 10YR or 7.5YR
Value 4 to 7 dry, 2 to 4 moist
Chroma 2 to 4, dry or moist
Texture fine sandy loam, loam
Gravel content 0 to 15 percent

C horizon (in Washington)
Hue - 10YR or 2.5Y
Value - 5 to 7 dry, 3 to 5 moist
Chroma - 2 to 4, dry or moist
Texture - loamy sand, sand
Gravel content 0 to 15 percent

C horizon (in Utah)
Hue - 7.5YR or 5YR
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 4 to 6 dry or moist, and is mottled
Texture - stratified loamy fine sand, very fine sandy loam, or light silty clay loam.

COMPETING SERIES: These are the Cabincreek, Conconully, Deno, Doublecreek, Fanal, Safety, Stevens, and Uhlig soils. Conconully and Stevens soils are 20 to 40 inches to densic materials (Cd horizon). Deno and Cabincreek soils have a lithic contact at 40 to 60 inches. Doublecreek soils have 10 percent cobbles in the upper subsoil and cobbles and stones in the substratum. Fanal soils are moderately well drained with redox concentrations in the lower part of the particle-size control section. Uhlig soils typically have silt loam textures in the particle-size control section and lack a loamy sand or sand substratum at depths of 30 to 60 inches. Safety soils have a paralithic contact at a depth of 20 to 40 inches.

GEOGRAPHIC SETTING: Phoebe soils formed in glacial outwash on outwash plains and terraces. Elevation is 1,300 to 2,600 feet in Washington and 4,900 to 5,000 feet in Utah. Slopes are 0 to 65 percent. The climate is characterized by relatively dry summers and cool moist winters. The mean annual precipitation is 15 to 25 inches. The average January temperature is 28 degrees F. and the average July temperature is about 68 degrees F. The mean annual temperature is 46 to 50 degrees F. The frost-free period is 100 to 150 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clayton, Dart, Garrison, Hallcreek, Hardesty, Hunters, Marble, Scala, and Springdale soils. Clayton and Scala soils have an ochric epipedon and are on terraces.. Dart soils are sandy throughout , have an ochric epipedon and are on terraces. Garrison soils are loamy-skeletal and are on outwash terraces. Hallcreek soils have a volcanic ash mantle 7 to 14 inches thick, are sandy-skeletal and are on outwash terraces. Hardesty soil have more than 60 percent volcanic ash and are on low terraces and alluvial fans. Hunters soils are fine-silty and are on terraces.. Marble soils are sandy, have E&Bt horizons with lamellae, have an ochric epipedon and are on terraces. Springdale soils are sandy-skeletal, have an ochric epipedon and are on terraces.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well-drained; slow runoff; high saturated hydraulic conductivity.

USE AND VEGETATION: These soils are used mainly for crop production, homesites and grazeable woodland. Small grains, alfalfa, peas, lentils, grasses, and potatoes are common crops. Potential natural vegetation in Washington is scattered ponderosa pine and an understory of common snowberry, dwarf rose, creeping Oregon-grape, pinegrass, blue wildrye, bluebunch wheatgrass, and Idaho fescue. In Utah, all of these soils are cultivated. The native vegetation is assumed to have been range.

DISTRIBUTION AND EXTENT: Eastern Washington; MLRA 44A. Series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Spokane County, Washington, 1964.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 25 inches (Ap, A, and Bw1 horizons)

Cambic horizon - the zone from 25 to 34 inches (Bw2 horizon)
Vitrandic feature - the zone from 0 to 16 inches (Ap and A horizon)

Particle-size control section - the zone from 10 to 40 inches with the zone from 10 to 34 inches qualifying as coarse-loamy with greater than 50 percent fine sand and coarser; and the zone from 34 to 40 inches qualifying as sandy. Family class based on weighted average.

Classification revised 6/92 from coarse-loamy, mixed, mesic Pachic Ultic Haploxerolls to coarse-loamy, mixed, mesic Vitrandic
Classification revised 10/01 from coarse-loamy, mixed, mesic Vitrandic Haploxerolls to coarse-loamy, mixed, superactive, mesic Vitrandic Haploxerolls.

The soils correlated as Phoebe in Utah are assumed to not meet criteria for Vitrandic subgroup and should be considered as a taxadjunct to the Phoebe series.

Description updated 4/2002 after revisiting the official type location.

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National Cooperative Soil Survey
U.S.A.