LOCATION NEPPEL WAEstablished Series
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Durinodic Xeric Haplocambids
TYPICAL PEDON: Neppel very fine sandy loam - grassland. (Colors are for dry soil unless otherwise noted.)
A--0 to 4 inches; grayish brown (10YR 5/2) very fine sandy loam, dark grayish brown (10YR 4/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many roots; neutral (pH 7.2); abrupt smooth boundary. (3 to 7 inches thick)
Bw--4 to 12 inches; brown (10YR 5/3) very fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; many roots; many very fine tubular pores; 3 percent gravel; slightly alkaline (pH 7.4); clear wavy boundary. (6 to 18 inches thick)
Bk1--12 to 20 inches; brown (10YR 5/3) very fine sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; many roots; many very fine tubular pores; 5 percent gravel; few secondary lime aggregates; slightly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (3 to 15 inches thick)
2Bkq--20 to 28 inches; light brownish gray (10YR 6/2) gravelly fine sandy loam, dark grayish brown (10YR 4/2) moist; massive; hard, firm, nonsticky and nonplastic; few roots; common very fine tubular pores; discontinuous weakly cemented lime-silica lenses 1/8 inch thick; 5 percent gravel; 25 percent durinodes; violently effervescent; strongly alkaline (pH 8.6); abrupt smooth boundary. (4 to 12 inches thick)
3Bk2--28 to 60 inches; white (10YR 8/1) extremely gravelly sand, grayish brown (10YR 5/2) moist; single grain; loose; few roots; 80 percent gravel and 5 percent cobbles; lime and silica coatings on undersides of pebbles and cobbles; violently effervescent; strongly alkaline (pH 8.6).
TYPE LOCATION: Adams County, Washington; about 1/4 mile south of Othello, 150 feet west and 800 feet south of the east quarter corner of sec. 3, T. 15 N. R. 29 E.
RANGE IN CHARACTERISTICS: Mean annual soil temperature at a depth of 20 inches ranges from 50 to 56 degrees F. These soils are usually dry in all parts between depths of 8 and 24 inches. Depth to the 3Bk horizon is 24 to 40 inches. The A and Bw horizons are neutral or slightly alkaline. The upper part of the particle-size control section has less than 50 percent fine or coarser sand and averages 2 to 10 percent pebbles and 0 to 2 percent cobbles and stones. The lower part of the particle-size control section contains 35 to 85 percent coarse fragments. The coarse fragments include 20 to 30 percent lime-silica cemented fragments.
The A horizon has value of 5 or 6 dry and chroma of 2 to 4 dry and moist.
The Bw horizon has value of 5 or 6 dry, 3 or 4 moist and chroma of 2 to 4 dry and moist. This horizon has weak subangular blocky or prismatic structure. It is loam, very fine sandy loam, or fine sandy loam. It is neutral or slightly alkaline.
The Bk1 horizon has value of 5 to 7 dry, 4 to 5 moist and chroma of 2 or 3 dry and moist. It is very fine sandy loam, loam, or fine sandy loam. It is slightly or moderately alkaline.
The 2Bkq horizon has hue of 10YR or 2.5Y and value of 6 or 7 dry, 4 or 5 moist and chroma of 2 or 3 dry or moist. It is gravelly fine sandy loam, gravelly very fine sandy loam, or very gravelly very fine sandy loam.
The 3Bk2 horizon has hue of 10YR or 2.5Y and value of 6, 7, or 8 dry, 4 or 5 moist and chroma of 1 to 3 dry or moist. It is extremely gravelly sand, very gravelly sand or extremely gravelly coarse sand.
COMPETING SERIES: These are the Buko, Connel and Idway series. Buko soils have a clay loam or silty clay loam B2 horizon with 18 to 35 percent clay and 40 to 60 percent silt. Connel soils are noncalcareous above the 2Bqk horizon, 10 to 20 inches to silica cementation and have 12 to 18 percent clay in the upper part of the control section. Idway soils are effervescent throughout and have soil temperatures of 47 to 52 degrees F.
GEOGRAPHIC SETTING: Neppel soils are on terraces and have slopes of 0 to 40 percent. They formed in alluvium or glacial outwash from basalt, lime-silica cemented material and granite with a mixture of loess in the upper part. Elevations are 400 to 1,300 feet. The climate is arid having an annual precipitation of 6 to 9 inches, and with dry summers and cool, moist winters. Average January temperature is 27 degrees F, average July temperature is 71 degrees F, and the mean annual temperature is 49 to 53 degrees F. The frost-free season is 135 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ephrata, Novark, Scoon, Scooteney, and Taunton soils. Ephrata and Novark soils on terraces and Scooteney soils on old alluvial fans lack discontinuous weakly cemented lime-silica lenses and durinodes within the 10- to 40-inch control section. Scoon soils on old alluvial fans and Taunton soils on terraces have a duripan within the 10- to 40-inch control section.
DRAINAGE AND PERMEABILITY: Well drained; very slow to medium runoff; moderate permeability in the upper part of the control section and very rapid in the coarse textured 3Bk horizon.
USE AND VEGETATION: Used for range and irrigated cropland. Common crops are winter wheat, alfalfa hay, corn, potatoes, and beans. Native vegetation is bluebunch wheatgrass, Sandberg bluegrass, rabbitbrush, and big sagebrush.
DISTRIBUTION AND EXTENT: South-central Washington. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Adams County, Washington, 1961.
REMARKS: Diagnostic horizons and features recognized in this pedon are an ochric epipedon from the surface to 4 inches, a cambic horizon from 4 to 12 inches, a zone of carbonate and silica accumulation from 20 to 28 inches, and a lithologic discontinuity to sandy-skeletal material at 28 inches.