LOCATION SKOVEN OREstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic, shallow Aridic Argixerolls
TYPICAL PEDON: Skoven extremely gravelly silt loam - on a 5 percent south slope, rangeland. (Colors are for moist soil unless otherwise noted.)
A--0 to 3 inches; very dark grayish brown (10YR 3/2) extremely gravelly silt loam, brown (10YR 5/3) dry; moderate medium platy structure parting to weak fine subangular blocky; slightly hard, friable, nonsticky and nonplastic; many very fine, fine and few medium roots; many very fine, fine and few medium irregular pores; 70 percent gravel; neutral (pH 7.0); clear smooth boundary. (3 to 5 inches thick)
Bt1--3 to 8 inches; dark brown (10YR 3/3) very gravelly silty clay loam, brown (10YR 5/3) dry; moderate medium subangular blocky structure; slightly hard, friable, sticky and plastic; common very fine and fine roots; common very fine and fine tubular pores; many distinct clay films on faces of peds and lining pores; 50 percent gravel; neutral (pH 7.0); abrupt wavy boundary. (4 to 7 inches thick)
Bt2--8 to 11 inches; reddish brown (5YR 4/4) extremely gravelly clay, yellowish red (5YR 5/6) dry; strong fine and medium subangular blocky structure; hard, firm, very sticky and very plastic; few very fine and fine roots; few very fine and fine tubular pores; continuous prominent clay films on faces of peds and lining pores; 70 percent gravel; neutral (pH 6.8); abrupt smooth boundary. (3 to 8 inches thick)
2Crkq--11 to 21 inches; paralithic tuff with silica and calcium carbonate coatings.
2R--21 inches; welded tuff of the Deschutes Formation. (see Remarks)
TYPE LOCATION: Wasco County, Oregon, about 1000 feet south and 2500 feet west of the NE corner of section 9, T.8 S., R.13 E. (Warm Springs Indian Reservation) (Latitude 44 degrees, 53 minutes, 18 seconds N, Longitude 121 degrees, 08 minutes, 20 seconds E)
RANGE OF CHARACTERISTICS: The soils are usually dry and are dry in all parts of the moisture control section for 120 to 150 days (cumulative) in the 4 months that follow the summer solstice. The mean annual soil temperature is 52 to 54 degrees F. Depth to bedrock of the Deschutes Formation is 10 to 20 inches. The solum has 10 to 30 percent volcanic glass and glass coated aggregate. The particle-size control section has 35 to 45 percent clay.
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 60 to 80 percent gravel.
The Bt horizon has hue of 10YR but may range to 5YR in the horizon above the bedrock contact. It has value of 3 or 4 moist, 4 or 5 dry and chroma of 3 to 6 moist and dry. It is very gravelly silty clay loam or extremely gravelly clay with 40 to 70 percent gravel.
The 2Crkq horizon is paralithic tuff of the Deschutes Formation.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Skoven soils are on nearly level to moderately sloping terraces. Elevations are 1400 to 2400 feet. Slopes are 0 to 15 percent. The soil formed in loess and colluvium over tuff or other components of the Deschutes Formation. 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 50 to 52 degrees F. The frost-free period is 110 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Antoken, Day, Lavey, Madras, and Simas soils. Antoken soils are on convex toe slopes of adjacent foothills and are greater than 60 inches to bedrock. Day soils are on adjacent foothills, greater than 60 inches to old sediments, and have a very fine particle-size class. Lavey soils are on terraces, 20 to 40 inches to bedrock and have a fine particle-size class. Madras soils are on terraces, are 20 to 40 inches to bedrock and have a fine-loamy particle-size class. Simas soils are on adjacent foothills, greater than 60 inches to old sediments, and have a fine particle-size class.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is slow.
USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. The native vegetation is Sandberg bluegrass, lomatium, bluebunch wheatgrass, buckwheat, and squirreltail.
DISTRIBUTION AND EXTENT: North-central Oregon; MLRA 10. The soils of this series are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Warm Springs Indian Reservation, Wasco County, Oregon, 1993.
REMARKS: Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - from the surface of the soil to a depth of 8 inches (A and Bt1 horizons).
Particle-size control section - from 3 to 11 inches (Bt1 and Bt2 horizons) with a weighted average of 39 percent clay and 57 percent gravel by field estimate.
Deschutes Formation - semiconsolidated water-laid sediments composed of sands, gravels, and silts of volcanic origin, and reworked volcanic materials. Inter bedded basalts and ash-flow tuffs are included in this formation.