LOCATION PATEROS WAEstablished Series
TAXONOMIC CLASS: Ashy-skeletal, glassy, mesic Vitrandic Haploxerepts
TYPICAL PEDON: Pateros cobbly ashy loam, in a complex with rock outcrop - forestland, on a 52 percent north-facing slope at an elevation of 1,250 feet. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures and spot plate reaction is used for pH values.)
A--0 to 7 inches; gray (10YR 6/1) cobbly ashy loam, very dark grayish brown (10YR 3/2) moist; weak medium granular structure; soft, friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial and tubular pores; 10 percent granitic gravel, 20 percent granitic cobbles and 3 percent granitic stones; neutral (pH 7.2); gradual wavy boundary. (4 to 7 inches thick)
Bw--7 to 18 inches; light gray (10YR 7/2) very cobbly ashy loam, dark grayish brown (10YR 4/2) moist; weak medium granular structure; loose, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine interstitial and tubular pores; 20 percent granitic gravel, 25 percent granitic cobbles and 10 percent granitic stones; slightly alkaline (pH 7.4); gradual wavy boundary. (11 to 16 inches thick)
C1--18 to 30 inches; very pale brown (10YR 8/2) extremely cobbly ashy fine sandy loam, grayish brown (10YR 5/2) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots matted around stones; few fine and medium interstitial pores; 20 percent granitic gravel, 40 percent granitic cobbles and 5 percent granitic stones; slightly alkaline (pH 7.6); gradual wavy boundary. (12 to 20 inches thick)
C2--30 to 60 inches; very pale brown (10YR 8/2) extremely cobbly ashy fine sandy loam, grayish brown (10YR 5/2) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots matted around stones; few fine and medium interstitial pores; 20 percent granitic gravel, 40 percent granitic cobbles and 15 percent granitic stones; neutral (pH 7.2).
TYPE LOCATION: Douglas County, Washington; approximately 1.5 miles southwest of Brewster; about 1,800 feet west and 1,500 feet north of the southeast corner of section 24, T. 30 N., R. 24 E. (Latitude 48 degrees 03 minutes 05 seconds N, Longitude 119 degrees 45 minutes 50 seconds W)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 48 to 50 degrees F. These soils are usually moist in the moisture control section but are dry for 75 to 90 consecutive days following the summer solstice. The particle-size control section has moist bulk density of 1.10 to 1.25 g/cc, volcanic glass content of 30 to 60 percent, including 0 to 5 percent sand-size pumice, 0.5 to 2.0 mm. in diameter, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.20 to 0.40 percent, Phosphate retention is 25 to 40, 15-bar water retention of 5 to 10 percent for air dried samples, 15 percent or more fine sand or coarser, 35 to 75 percent rock fragments, and an apparent field estimated clay content of 5 to 10 percent. The solum has base saturation (NH4OAc) of 75 to 100 percent.
The A horizon has a value of 5 or 6 dry and chroma is 1 or 2 dry or moist.
The Bw horizon has a value of 6 or 7 dry and 4 or 5 moist. Chroma is 1 or 2 dry or moist. It contains 50 to 65 percent rock fragments. The fine earth fraction is ashy fine sandy loam or ashy loam. Reaction ranges from neutral to slightly alkaline.
The C horizon has a value of 6 to 8 dry and 4 to 6 moist. Chroma is 1 or 2 dry and 2 or 3 moist. It contains 55 to 75 rock fragments. Reaction ranges from neutral to slightly alkaline.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Pateros soils are on scarp slopes of plateaus that have a northly aspect. Slopes are 25 to 70 percent. These soils formed in colluvium from granite. Elevation is 1,000 to 3,000 feet. The climate is characterized by warm, dry summers and cool, moist winters. Average annual precipitation is 15 to 18 inches. Average January temperature is about 25 degrees F.; average July temperature is about 68 degrees F.; and average annual temperature is 46 to 48 degrees F. Frost-free season is 110 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ginnis, Swakane and Logy series. Ginnis and Swakane soils are on upland sideslopes and have bedrock at depths less than 40 inches. Logy soils are on fans and are usually dry and have less than 30 percent volcanic ash in the control section.
DRAINAGE AND PERMEABILITY: Well drained, medium to rapid runoff; moderate permeability.
USE AND VEGETATION: Pateros soils are primarily used for timber production and livestock grazing. The potential native vegetation is Douglas fir and Ponderosa pine with an understory of Idaho fescue, bluebunch wheatgrass, pussytoes, serviceberry, and ocean spray.
DISTRIBUTION AND EXTENT: North Central Washington. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon.
SERIES ESTABLISHED: Douglas County, Washington, 1998.
REMARKS: Diagnostic features and horizons recognized in this pedon are an ochric epipedon from the surface to 7 inches, 30 to 60 percent volcanic glass in the fine earth fraction of the control section and over 35 percent granitic rock fragments in the control section.
ADDITIONAL DATA: Partial laboratory data is available for this pedon, NSSL pedon number 93P 368.