LOCATION TETHEROW OREstablished Series
TAXONOMIC CLASS: Loamy over pumiceous or cindery, mixed, superactive, mesic Vitritorrandic Haploxerolls
TYPICAL PEDON: Tetherow ashy sandy loam - rangeland, on a nearly level volcanic plain at 2750 feet elevation. (When described (4/9/86), the soil was moist throughout. Colors are for dry soil unless otherwise noted.)
Ap--0 to 6 inches; brown (10YR 5/3) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; slightly hard, friable, nonsticky and nonplastic; common very fine roots; many very fine irregular pores; slightly alkaline (pH 7.4); clear smooth boundary. (3 to 7 inches thick)
A--6 to 19 inches; brown (10YR 5/3) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and few fine irregular pores; 5 percent gravel; slightly alkaline (pH 7.6); clear wavy boundary. (3 to 15 inches thick)
AC--19 to 24 inches; pale brown (10YR 6/3) cobbly ashy sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; slightly hard, firm, nonsticky and nonplastic; common very fine roots; many very fine irregular pores; few medium subangular concretions; 20 percent cobbles; slightly alkaline (pH 7.4); clear wavy boundary. (0 to 7 inches thick)
2C--24 to 60 inches; dark reddish brown (5YR 3/4) moist and dry cinders; single grain.
TYPE LOCATION: Deschutes County, Oregon; 0.5 miles northwest of Terrebonne, adjacent to cinder pit, 1200 feet south and 50 feet east of the northwest corner of section 28, T. 14 S., R. 12 E. (Latitude 44 degrees, 21 minutes, 36 seconds N, Longitude 121 degrees, 11 minutes, 13 seconds W)
RANGE IN CHARACTERISTICS: These soils are usually dry and are dry in all parts of the soil moisture control section for 120 to 150 days (cumulative) after the summer solstice. The mean annual soil temperature is 48 to 52 degrees F. The depth to bedrock is greater than 60 inches. Solum thickness and depth to cinders is 14 to 28 inches. Reaction is neutral to slightly alkaline. The upper part (solum) contains 15 to 30 percent glass and glass-coated aggregate, and the acid oxalate extractable aluminum plus one-half the acid oxalate extractable iron is 0.40 to 0.80 percent. Phosphate retention is 15 to 25 percent. The mollic epipedon is 7 to 12 inches thick. Base saturation is 80 to 100 percent. The solum contains 5 to 10 percent clay and 55 to 75 percent sand dominantly very fine and fine sand.
The A horizon has hue of 10YR, value of 2 or 3 moist and 5 dry and chroma of 2 or 3 moist and dry. It contains 0 to 10 percent gravel.
The AC horizon has chroma of 2 or 3 moist and dry. It contains 0 to 25 percent cobbles, and 0 to 10 percent gravel. It is ashy sandy loam or cobbly ashy sandy loam.
The C horizon has hue of 10YR and 5YR, value of 3 moist and 5 or 6 dry and chroma of 3 moist and 3 or 4 dry. It contains 90 to 100 percent cinders (greater than 2.0 millimeters). In some pedons, this horizon has thin brittle discontinuous layers.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Tetherow soils are on cinder cones and volcanic plains at elevations of 2,500 to 4,000 feet. Slopes are 0 to 50 percent. The soils formed in weathered ash over cinders. The climate is characterized by cool, moist winters and hot, dry summers. The mean annual precipitation is 10 to 12 inches. The mean annual temperature is 47 to 52 degrees F. The frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Deschutes, Redmond and Stukel soils. Deschutes and Stukel soils are on lava plains and over basalt. Redmond soils are on lava plains and are fine-loamy. These soils lack the cinders.
DRAINAGE AND PERMEABILITY: Excessively drained; moderately rapid permeability.
USE AND VEGETATION: These soils are used for irrigated crops, hay and pasture, livestock grazing, and wildlife habitat. Potential native vegetation is western juniper, antelope bitterbrush, mountain big sagebrush, Idaho fescue, bluebunch wheatgrass, Sandberg bluegrass, and needleandthread.
DISTRIBUTION AND EXTENT: Deschutes Basin of central Oregon; MLRA 10. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Deschutes County (Upper Deschutes River Area), Oregon, 1992.
REMARKS: Diagnostic horizons and features in this pedon are:
mollic epipedon - from the soil surface to about 8 inches (Ap, part of the A2 horizon).
Vitritorrandic - the very fine sand fraction contains about 19 percent glass and glass-coated aggregate. The acid oxalate extractable aluminum plus one half the acid oxalate extractable iron is 0.40 to 0.80 percent. Laboratory data is based on the associated Deschutes Series, pedon S87OR-017-002.
The ash mantle is a deposit from Mt. Mazama.