LOCATION FINAL OREstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Xerertic Natrargids
TYPICAL PEDON: Final silt loam - rangeland, on a 1 percent slope at an elevation of 3730 feet. (When described on August 7, 1991 the soil was dry 0 to 7 inches, and moist 7 to 60 inches. Colors are for moist soil unless stated otherwise.)
A--0 to 3 inches; very dark grayish brown (10YR 3/2) silt loam, gray (10YR 6/1) dry; moderate very coarse platy structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine vesicular pores; SAR of 42, EC of 4; moderately alkaline (pH 8.0); abrupt smooth boundary. (1 to 4 inches thick)
Btn1--3 to 7 inches; very dark gray (10YR 3/1) clay, grayish brown (10YR 5/2) dry; weak fine and medium prismatic structure parting to strong very fine, fine and medium angular blocky; very hard, firm, very sticky and very plastic; many very fine and fine, common medium and few coarse roots; common very fine tubular pores; many faint clay films on the faces of peds and lining pores; moderately alkaline (pH 8.2); clear smooth boundary.
Btn2--7 to 12 inches; dark grayish brown (10YR 4/2) clay, light brownish gray (10YR 6/2) dry; moderate very fine, fine and medium subangular blocky structure; hard, friable, very sticky and very plastic; common very fine, fine and medium and few coarse roots; common very fine and fine tubular pores; many faint clay films on the faces of peds and lining pores; strongly effervescent; SAR of 56, EC of 8; strongly alkaline (pH 8.6); gradual smooth boundary. (Combined thickness of the Btn horizon is 6 to 28 inches thick)
2Bn--12 to 24 inches; dark grayish brown (2.5Y 4/2) clay, light brownish gray (10YR 6/2) dry; weak fine and medium subangular blocky structure; hard, friable, very sticky and very plastic; common very fine, fine and medium roots; common very fine and fine tubular pores; many faint organic coatings on the faces of peds and lining pores; strongly effervescent; SAR of 80, EC of 14; strongly alkaline (pH 8.8); gradual smooth boundary. (8 to 15 inches thick)
2Bkn1--24 to 42 inches; very dark grayish brown (2.5Y 3/2) clay loam, light brownish gray (2.5Y 6/2) dry; weak fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and fine roots; common very fine and fine tubular pores; many faint organic coatings on the faces of peds and lining pores; lime in filaments; strongly effervescent; SAR of 99, EC of 12; very strongly alkaline (pH 9.2); gradual smooth boundary. (10 to 20 inches thick)
2Bkn2--42 to 60 inches; dark grayish brown (2.5Y 4/2) silty clay loam, light brownish gray (2.5Y 6/2) dry; weak medium and fine subangular blocky structure; hard, firm and brittle, moderately sticky and moderately plastic; common very fine and fine roots; common very fine and fine tubular pores; many faint organic coatings on the faces of peds and lining pores; 5 percent fine gravel; lime in filaments; SAR of 112, EC of 8; strongly effervescent; very strongly alkaline (pH 9.2)
TYPE LOCATION: Harney County, Oregon, about 3 miles south of Bartlett Mountain, about 1600 feet north and 200 feet east of the southwest corner section 10, T.22S., R.35E. (Latitude 43 degrees, 40 minutes, 21.0 seconds N, Longitude 118 degrees 24 minutes 33.0 seconds W)
RANGE IN CHARACTERISTICS: The soils have an aridic bordering on xeric soil moisture regime. The mean annual soil temperature 47 to 51 degrees F. Depth to bedrock and solum thickness is more than 60 inches. The particle-size control section averages 40 to 50 percent clay. The soil reaction is moderately to very strongly alkaline increasing with depth. Depth to the natric horizon is 1 to 4 inches. A water table is present in May and June at depths of 1.0 to 2.5 feet.
The A horizon has a moist value of 3 or 4, and a chroma moist and dry of 1 through 3. It has 1 to 2 percent organic matter. It has SAR values of 25 to 45, and an EC of 2 to 4 mmhos.
The Btn horizon has a hue of 10YR and 2.5Y. It is clay, or silty clay with 40 to 55 percent clay. It has SAR values of 30 to 60, and an EC of 4 to 8 mmhos. It has 1 to 2 percent organic matter.
The 2Bn horizon has a hue of 10YR or 2.5Y. It is clay or silty clay with 40 to 50 percent clay. It has SAR values of 50 to 90 and EC of 8 to 16 mmhos.
The 2Bkn horizon has dry values of 6 and 7. It has SAR values of 80 to 120. It is clay loam or silty clay loam with 27 to 40 percent clay. EC is 4 to 16 mmhos with the upper part ranging from 8 to 16 mmhos.
COMPETING SERIES: This is the Bullion series. Bullion soils have hue of 7.5YR or 5YR and have significant accumulations of calcium carbonate and gypsum below the natric horizon.
GEOGRAPHIC SETTING: Final soils are on stream terraces and have slopes of 0 to 2 percent. The soils formed in alluvium from mixed igneous rock sources. Elevations are 3500 feet to 4000 feet. 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 45 to 49 degrees F. The frost free period is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the Jett series. The Jett soils are on lower stream terraces and have a mollic epipedon.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained, slow permeability. The soils have an apparent water table at depths of 12 to 30 inches from May to June. The soil surface is saturated in the spring due to the slow permeability of the subsoil and spring snowmelt.
USE AND VEGETATION: The soils are used for livestock grazing. Potetial native plant community is black greasewood, basin wildrye, and inland saltgrass.
DISTRIBUTION AND EXTENT: Stream terraces in southeast Oregon; MLRA 10. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Harney County, Oregon, 1997.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon
Natric horizon - from 3 to 7 inches (Btn1 horizon); based on SAR and structure.
Argillic horizon - from 3 to 60 inches
Water table at 1.0 to 2.5 feet from May to June. (Aquic subgroup criteria)
Vertic subgroup - The upper meter has a linear extensibility of 6.0 cm.
Particle-size control section - from 3 to 23 inches is about 47 percent clay.
ADDITIONAL DATA: Partial lab data is available for this pedon. Reference sample S92OR-025-003 from Harney County, Oregon, NSSL, Lincoln, NE.