LOCATION OREANNA OREstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Typic Haplocambids
TYPICAL PEDON: Oreanna gravelly sandy clay loam on a 2 percent slope, rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 7 inches; pale brown (10YR 6/3) gravelly sandy clay loam, dark brown (10YR 3/3) moist; moderate thin platy structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine, fine, medium, and coarse roots; many very fine and fine vesicular and irregular pores; 20 percent gravel; moderately alkaline (pH 8.2); clear smooth boundary. (5 to 9 inches thick)
Bw1--7 to 14 inches; pale brown (10YR 6/3) sandy clay loam, dark brown (10YR 3/3) moist; moderate coarse subangular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; few very fine, fine, and medium roots; many very fine and fine irregular pores; 5 percent gravel; moderately alkaline (pH 8.0); clear smooth boundary. (6 to 12 inches thick)
Bw2--14 to 21 inches; pale brown (10YR 6/3) gravelly sandy clay loam, dark yellowish brown (10YR 3/4) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine irregular pores; 30 percent rounded gravel; 10 percent or horizon is brittle; moderately alkaline (pH 8.2); gradual wavy boundary. (5 to 10 inches thick)
2C--21 to 43 inches; very pale brown (10YR 7/3) very gravelly loamy coarse sand, dark yellowish brown (10YR 4/4) moist; single grained; loose, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine irregular pores; 55 percent rounded gravel; 5 percent of horizon is brittle; moderately alkaline (pH 8.4); gradual wavy boundary. (18 to 26 inches thick)
3Ck1--43 to 50 inches; very pale brown (10YR 7/3) very gravelly sandy loam, yellowish brown (10YR 5/4) moist; massive; slightly hard, very friable, slightly sticky and nonplastic; few very fine roots; many very fine and fine irregular pores; strongly effervescent-disseminated lime; 50 percent rounded gravel; strongly alkaline (pH 8.6); clear wavy boundary. (0 to 10 inches thick)
4Ck2--50 to 60 inches; white (2.5Y 8/2) loamy sand, very pale brown (10YR 7/3) moist; single grained; loose, nonsticky and nonplastic; many very fine irregular pores; strongly effervescent-disseminated lime; 5 percent gravel; 5 percent of horizon is brittle; strongly alkaline (pH 8.6).
TYPE LOCATION: Harney County, Oregon; on the eastern edge of Pueblo Valley about 3 miles north of the Calderwood Desert Well in the NE1/4NW1/4 section 3, T. 37 S., R. 34 E.
RANGE IN CHARACTERISTICS: The soils are dry for over three-fourths of the time when the soil temperature is greater than 41 degrees F. The soil temperature is above 41 degrees F. from about March 15 to about November 15. The soil is dry from 8 to 21 inches from about June 15 to about November 15. The mean annual soil temperature is 47 to 50 degrees F. Depth to the 2C horizon is 20 to 30 inches. Rock fragments in the upper part of the particle-size control section range from 5 to 30 percent, and in the lower part from 40 to 60 percent. They are dominantly gravel. Clay in the upper part of the particle-size control section ranges from 20 to 30 percent, and in the lower part averages from 0 to 10 percent. The upper part is more than 15 percent coarser than very fine sand.
The A horizon has value of 5 or 6 dry and 3 or 4 moist, and chroma of 3 or 4 moist and dry. It has 1 to 2 percent organic matter.
The Bw horizon has value of 5 or 6 dry and 3 or 4 moist, and chroma of 3 or 4 moist and dry. It is sandy clay loam, gravelly sandy clay loam, or clay loam.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Oreanna soils are on old beach terraces at elevations of 4000 to 4500 feet. Slopes are 0 to 3 percent. The soils formed in alluvium and lacustrine sediments. The climate is characterized by cold dry winters and warm dry summers. The mean annual precipitation is 6 to 10 inches and the mean annual temperature is 45 to 49 degrees F. The frost-free period is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Als, Alvodest and Davey soils. Als soils lack a cambic horizon and are sandy. Alvodest soils have SAR greater than 13 and are fine. Davey soils are sandy.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability in the upper part and moderately rapid in the lower part.
USE AND VEGETATION: The soils are used for rangeland. Vegetation commonly is shadscale, bud sagebrush, Indian ricegrass, and bottlebrush squirreltail.
DISTRIBUTION AND EXTENT: Southeastern Oregon; MLRA 24. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Harney County, Oregon, 1997.
REMARKS: Diagnostic horizons and other features recognized in this pedon are:
- Ochric epipedon.
- Cambic horizon - from 7 to 21 inches.