LOCATION AYRESBUTTE OREstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Vitritorrandic Durixerolls
TYPICAL PEDON: Ayresbutte gravelly ashy sandy loam, on a 3 percent slope, rangeland. (Colors are for moist soils unless otherwise noted.)
A-- 0 to 3 inches; very dark grayish brown (10YR 3/2) gravelly ashy sandy loam, brown (10YR 5/3) dry; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine roots; common very fine interstitial pores; 25 percent gravel; 30 percent sand-size (0.25 to 1.0 mm.) pumice, very pale brown (10YR 7/3) dry; slightly alkaline (pH 7.8); clear wavy boundary (3 to 7 inches thick).
AB-- 3 to 10 inches; dark brown (10YR 3/3) very gravelly ashy sandy loam, brown (10YR 5/3) dry; weak fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; common fine roots and few very fine; common very fine tubular pores; 30 percent gravel and 10 percent cobbles; 20 percent sand-size (0.25 to 1.0 mm.) pumice, very pale brown (10YR 7/3) dry; slightly alkaline (pH 7.8); clear wavy boundary (4 to 10 inches thick).
2Bt1-- 10 to 16 inches; brown (10YR 4/3) very cobbly loam, pale brown (10YR 6/3) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine and few very fine roots; few very fine tubular pores; few faint clay films on faces of peds; 25 percent gravel and 30 percent cobbles; slightly alkaline (pH 7.8); clear wavy boundary.
2Bt2-- 16 to 23 inches; dark yellowish brown (10YR 4/4) extremely cobbly clay loam, very pale brown (10YR 7/3) dry; moderate fine subangular block structure parting to moderate very fine subangular blocky; slightly hard, friable, slightly sticky and moderately plastic; few very fine roots; few very fine tubular pores; common distinct clay films on faces of peds and lining pores; 35 percent gravel and 30 percent cobbles; slightly alkaline (pH 7.8); clear wavy boundary. (Combined thickness of 2Bt horizon ranges from 8 to 20 inches.)
2Bk-- 23 to 26 inches; yellowish brown (10YR 5/4) extremely cobbly loam, very pale brown (10YR 7/3) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; slightly effervescent with carbonate pendants on lower side of rock fragments; 50 percent gravel and 35 percent cobbles; slightly alkaline (pH 7.6); abrupt wavy boundary. (2 to 4 inches thick)
2Bkqm-- 26 to 60 inches; indurated pan, with cemented subrounded gravel and cobble fragments; strongly effervescent with disseminated lime on rock fragments.
TYPE LOCATION: Crook County, Oregon; located 600 feet south and 2000 feet east of the NW corner of section 10, T. 16 S., R. 14 E.; about 3 miles southwest of the community of Powell Butte.
RANGE IN CHARACTERISTICS: The soils are dry for one-half to three-fourths of the time when the soil temperature is above 41 degrees F. They are usually dry, and are dry in the moisture control section for 90 to 120 cumulative days following the summer solstice. The mean annual temperature is 50 to 54 degrees F. Depth to the duripan is 20 to 40 inches. Depth to bedrock is greater than 60 inches. The mollic epipedon is 7 to 14 inches thick, phosphate retention of 15 to 25 glass and glass-coated aggregate and acid oxalate aluminum plus one-half the iron of 0.4 to 0.8 percent. The particle-size control section averages over 50 percent rock fragments.
The A horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and dry. It contains 15 to 30 percent rounded gravel and 0 to 15 percent rounded cobbles.
The AB horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and dry. It contains 20 to 40 percent rounded gravel and 10 to 20 percent rounded cobbles.
The 2Bt horizon has value of 3 or 4 moist, 6 or 7 dry, and chroma of 3 or 4 moist and dry. It is clay loam, loam, or sandy clay loam and contains 20 to 35 percent rounded gravel and 20 to 50 percent rounded cobbles and 25 to 35 percent clay.
The 2Bk horizon has value of 4 or 5 moist, 6 or 7 dry, and chroma of 3 or 4 moist and dry. It contains 40 to 60 percent rounded gravel and 20 to 40 percent rounded cobbles.
The 2Bkqm horizon is very strongly cemented or indurated to a depth of 40 inches or more.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Ayresbutte soils are on alluvial fans and fan remnants at elevations of 3,100 to 3,500 feet. Slopes range from 0 to 8 percent. These soils formed in colluvium derived from rhyolite with an influence of volcanic ash in the surface. The climate is characterized by cool moist winters and hot dry summers. The mean annual precipitation is 9 to 12 inches, the mean annual temperature is 48 to 52 degrees F., and the frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ayres, Deschutes, Redmond, Stukel and Stukmond soils. Ayres soils are shallow to a duripan and lack the ashy surface textures. Deschutes and Redmond soils lack the duripan and have bedrock at 20 to 40 inches. Stukel and Stukmond soils are shallow to bedrock and lack a duripan.
DRAINAGE AND PERMEABILITY: Well drained, permeability is moderately slow above the duripan and very slow through the duripan.
USE AND VEGETATION: Ayresbutte soils are used mainly for livestock grazing and wildlife habitat. The native vegetation is Idaho fescue, bluebunch wheatgrass, and mountain big sagebrush.
DISTRIBUTION AND EXTENT: Central Oregon; MLRA 10, pumice zone. This series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Upper Deschutes River Area, Oregon; 2006.
REMARKS: Diagnostic horizons and features include:
Mollic epipedon - from the surface to a depth of 10 inches (A and AB horizons)
Argillic horizon - the zone from 10 to 23 inches (2Bt horizon)
Indurated duripan - from a depth of 26 to 60 inches (2Bkqm horizon)
Vitritorrandic feature - from the surface to a depth of 10 inches (A and AB horizons)
The series was established in 2006 with the addition of the series to the Upper Deschutes River Area, Oregon soil survey legend in order to have a seamless join with the Crook County Area soil survey, Prineville part.