LOCATION POMERENING OREstablished Series
TAXONOMIC CLASS: Ashy, glassy, nonacid, frigid Vitrandic Torriorthents
TYPICAL PEDON: Pomerening very gravelly loamy sand - rangeland, on a 2 percent slope at an elevation of 4240 feet. (Colors are for dry soil unless otherwise stated.)
A1--0 to 4 inches; reddish gray (5YR 5/2) very gravelly loamy sand, dark reddish brown (5YR 3/2) moist; single grained; loose, nonsticky and nonplastic; common very fine and few fine roots; common very fine and fine, and few medium and coarse irregular pores; 35 percent gravel size cinders; slightly alkaline (pH 7.4); clear smooth boundary.
A2--4 to 9 inches; reddish brown (5YR 5/3) very gravelly loamy coarse sand, dark reddish brown (5YR 3/3) moist; single grained; loose, nonsticky and nonplastic; many very fine, common fine and few medium roots; common very fine, fine and medium, and few coarse irregular pores; 30 percent gravel size cinders and 5 percent cobbles; slightly alkaline (pH 7.5); clear smooth boundary. (Combined thickness of the A horizons 4 to 20 inches thick)
C1--9 to 34 inches; weak red (2.5YR 5/2) gravelly loamy coarse sand, dusky red (2.5YR 3/2) moist; single grained; loose, nonsticky and nonplastic; few very fine and fine roots; common very fine, fine, medium and coarse random and irregular pores; 20 percent gravel size cinders; slightly alkaline (pH 7.5); diffuse wavy boundary.
C2--34 to 62 inches; weak red (2.5YR 5/2) gravelly loamy coarse sand, dusky red (2.5YR 3/2) moist; single grained; loose, nonsticky and nonplastic; few very fine roots; common very fine, fine and medium, and few coarse random irregular pores; 20 percent gravel and 5 percent cobbles size cinders; slightly alkaline (pH 7.5).
TYPE LOCATION: Harney County, Oregon, in the Diamond Craters Outstanding Natural Area, about 100 feet north and 2,550 feet east of the southwest corner of section 29, T. 28 S., R. 32 E., on the Diamond Swamp quadrangle. (Latitude 43 degrees, 6 minutes, 12 seconds, Longitude 118 degrees, 47 minutes, 21 seconds)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 45 to 47 degrees F. The soil moisture control section is dry for one-half to three-forths of the time when the soil temperature is above 41 degrees F. Phosphate retention is 10 to 20 percent. Volcanic glass is 70 to 90 percent. The acid oxalate aluminum plus one-half the iron is 0.3 to 0.7 percent. The mollic colors throughout the profile are from the parent material. Bedrock is at a depth of greater than 60 inches. The particle size control section averages 25 to 35 percent gravel sized cinders, and 2 to 10 percent clay. A Bk or Ck horizon is present in some pedons; when present carbonates are below 20 inches.
The A horizon hue is 5YR, 7.5YR and 10YR. It has 35 to 60 percent cinders. Clay content is 5 to 15 percent.
The C horizon hue is 2.5YR, 5YR, or 7.5YR. It is gravelly loamy coarse sand, gravelly loamy sand and very gravelly loamy coarse sand. Rock fragment content is 20 to 45 percent cinders. Clay content is 2 to 10 percent. Reaction is slightly or moderately alkaline.
COMPETING SERIES: There are no competing series in this family.
GEOGRAPHIC SETTING: Pomerening soils are on hills and have slopes of 2 to 20 percent. The soils formed in cinders. Elevation is 4,100 to 4,700 feet. The climate is characterized by cold, moist winters and hot dry summers. The mean annual precipitation is 10 to 12 inches. The mean annual temperature is 43 to 45 degrees F. The frost free period is 50 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aval, and Flank soils. Aval and Flank soils have bedrock at less than 20 inches.
DRAINAGE AND PERMEABILITY: Excessively drained, very rapid permeability.
USE AND VEGETATION: The soils are used for wildlife habitat. Potential native vegetation is basin big sagebrush, needleandthread, and Thurber needlegrass.
DISTRIBUTION AND EXTENT: Holocene age volcanic areas of southeastern Oregon; MLRA 23. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Harney County, Oregon, 1997.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon
Andic soil properties are not met because phosphate retention is less than 25 percent. The profile is high in volcanic glass.