LOCATION STRAT WA
Established Series
Rev. VB/RJE/TLA
01/2011
STRAT SERIES
The Strat series consists of very deep, well drained soils formed in glacial outwash, mixed with loess in the upper part. Strat soils are on glacial outwash plains, terraces, kames, and valley trains and in glacial drainage channels. Slopes are 0 to 70 percent. The mean annual precipitation is about 10 inches and the mean annual temperature is about 49 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Calcidic Haploxerolls
TYPICAL PEDON: Strat very stony silt loam, grassland. (Colors are for dry soil unless otherwise stated.)
A--0 to 10 inches; brown (10YR 5/3) very stony silt loam, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine roots; many fine and medium tubular pores; 15 percent gravel, 15 percent cobbles, , 10 percent stones; slightly alkaline (pH 7.6); clear smooth boundary. (8 to 15 inches thick)
Bw1--10 to 18 inches; pale brown (10YR 6/3) very cobbly loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft very friable, nonsticky and nonplastic; common fine roots; few tubular pores; 20 percent pebbles, 35 percent cobbles; slightly alkaline (pH 7.8); gradual smooth boundary. (7 to 13 inches thick)
Bw2--18 to 22 inches; yellowish brown (10YR 5/4) very gravelly loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; few fine roots; few fine tubular pores; 40 percent gravel and 15 percent cobbles; slightly alkaline (pH 7.8); abrupt wavy boundary. (0 to 12 inches thick)
2Bkq--22 to 60 inches; yellowish brown (10YR 5/4) extremely gravelly sand, dark yellowish brown (10YR 4/4) moist; single grained; loose, nonsticky and nonplastic; 65 percent gravel, 10 percent cobbles, and 5 percent stones; rock fragments dominantly basalt with white silica and lime coatings on lower side; slightly effervescent on coated rock fragments, slightly alkaline (pH 7.8).
TYPE LOCATION: Douglas County, Washington; 360 feet east of the southwest corner sec. 31, T.23N., R.25E., W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature 51 to 53 degrees F. These soils are usually dry in all parts between a depth of 8 and 24 inches for more than half the time when the soil temperature is greater than 41 degrees F (105 to 115 consecutive days). The depth to the 2Bkq horizon and and secondary carbonates is 20 to 36 inches. The particle-size control section averages 35 to 80 percent rock fragments and 5 to 12 percent clay.
The A horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 moist or dry. Reaction is neutral or slightly alkaline.
The Bw horizon has value of 5 or 6 dry, 3 or 4 moist, and chroma of 3 or 4 moist or dry. It is cobbly, very cobbly, or very gravelly silt loam, loam, sandy loam, or fine sandy loam. Reaction is neutral to moderately alkaline.
The 2Bkq horizon is multicolored or has hue of 10YR or 2.5Y, has value of 5 through 7 dry, 3 through 6 moist, and chroma of 1 through 4 moist or dry. It is dominantly sand or coarse sand with 35 to 90 percent rock fragments. The upper 4 to 7 inches is loamy sand in some pedons. The rock fragments have white lime-silica coatings. Reaction is slightly alkaline or moderately alkaline.
COMPETING SERIES: These are the
Haystack,
Heytou,
Nighthawk,
Olex,
Peshastin, and
Redcanyon series. The Haystack series are dry for 120 to 150 cumulative days, have 15 to 25 percent clay in the particle-size control section and lack a Bkq horizon. The Heytou soils have dense glacial till (Cd) at 20 to 40 inches. Nighthark have a sandy loam or loam fine-earth texture in the lower part of the particle-size control section. Peshastin soils have a sandy loam or fine sandy loam fine-earth texture in the lower par tof the particle-size section. The Olex series has a mean annual soil temperature of 55 to 59 degrees F, and has a silt loam cambic horizon. The Redcanyon series are 20 to 40 inches deep to lithic contact, have a mean annual soil temperature of 47 to 50 degrees and 18 to 30 percent clay in the particle-size control section.
GEOGRAPHIC SETTING: These soils have simple or complex topography and are on smooth, undulating, rolling or hilly slopes on glacial outwash plains, terraces, kames and valley trains and in glacial drainage channels at elevations of 600 to 2,800 feet. They formed in glacial outwash, mixed with loess in the upper part. Slopes are 0 to 70 percent. Summers are warm and dry and winters are cool and moist. The mean annual precipitation is 9 to 12 inches. The average January temperature is 26 degrees F.; the average July temperature is 73 degrees F.; and the average annual temperature is 49 degrees F. The frost free season is about 130 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Bakeoven,
Delrio,
Esquatzel,
Lickskillet,
Renslow,
Skaha and
Stratford soils. Delrio, Esquatzel and Renslow soils lack coarse fragments in the particle size control section. Bakeoven and Lickskillet soils have a lithic contact at a depth of less than 20 inches. Stratford soils have less than 35 percent rock fragments in the upper part of the particle size control section. Skaha soils are sandy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate or moderately rapid permeability in the Bw1 and Bw2 horizons and very rapid permeability in the 2Bkq horizon.
USE AND VEGETATION: Mainly grazing, with a small amount in dryland grain production and irrigated crops. Native vegetation is big sagebrush, bluebunch wheatgrass, and Sandberg bluegrass.
DISTRIBUTION AND EXTENT: Eastern, central and northcentral Washington. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Douglas County, Washington, 1978.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - 0 to 10 inches (A horizon)
Cambic horizon - 10 to 22 inches (Bw1 and Bw2 horizons)
Secondary lime coatings - 22 to 60 inches (2Bkq horizon)
PSCS - zone from 10 to 40 inches (Bw1, Bw2 and part of the 2Bkq horizon). The PSCS averages 77 percent rock fragments.
National Cooperative Soil Survey
U.S.A.