LOCATION LOOKOUT OREstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Abruptic Xeric Argidurids
TYPICAL PEDON: Lookout stony silt loam, rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 4 inches; light brownish gray (10YR 6/2) stony silt loam, very dark grayish brown (10YR 3/2) moist; moderate thin platy structure parting to weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine irregular pores; about 20 percent cobbles and stones; neutral (pH 6.6); clear smooth boundary. (3 to 7 inches thick)
A2--4 to 9 inches; light brownish gray (10YR 6/2) stony silt loam, very dark grayish brown (10YR 3/2) moist; weak coarse prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine tubular pores; 30 percent stones and cobbles; neutral (pH 6.6); abrupt smooth boundary. (4 to 7 inches thick)
2Bt1--9 to 14 inches; brown (10YR 5/3) cobbly clay, dark brown (10YR 3/3) moist; moderate medium and fine prismatic structure parting to strong fine blocky; very hard, very firm, very sticky and very plastic; common very fine roots; common very fine tubular pores; common clean light gray very fine sand and silt coatings on faces of peds; continuous thick clay film on peds and in pores; about 20 percent flat basalt cobbles on top of horizon; mildly alkaline (pH 7.5); clear smooth boundary. (4 to 10 inches thick)
2Bt2--14 to 17 inches; brown (10YR 4/3) clay, dark brown (10YR 3/3) moist; moderate medium and fine prismatic structure parting to strong fine blocky; very hard, very firm, very sticky and very plastic; common very fine roots; common very fine tubular pores; few clean light gray very fine sand and silt coatings on faces of peds; continuous thick clay films on peds and in pores; moderately alkaline (pH 8.2); clear smooth boundary. (3 to 8 inches thick)
2Btk--17 to 21 inches; yellowish brown (10YR 5/4) clay, dark yellowish brown (10YR 4/4) moist; moderate fine subangular blocky structure; hard, firm, sticky and plastic; few roots; common very fine tubular pores; many moderately thick clay films on peds; strongly effervescent with disseminated lime; moderately alkaline (pH 8.2); abrupt smooth boundary. (2 to 8 inches thick)
2Bk--21 to 24 inches; light yellowish brown (10YR 6/4) loam, dark yellowish brown (10YR 4/4) moist; massive; hard, friable, slightly sticky and slightly plastic; few roots; common very fine tubular pores; strongly effervescent with disseminated lime; moderately alkaline (pH 8.3); abrupt smooth boundary. (0 to 8 inches thick)
2Bkqm--24 to 45 inches; very pale brown (10YR 7/3) silica-lime cemented duripan; platy; indurated plates with weakly cemented material between plates; laminar coating on surfaces of plates; 20 percent rock fragments; abrupt wavy boundary. (10 to 25 inches thick)
3R--45 inches; basalt.
TYPE LOCATION: Union County, Oregon; about 2 1/2 miles northeast of North Powder, 270 feet south of the intersection of the road and power line; 40 feet west of road in NE1/4NW1/4SE1/4 sec. 2, T. 6 S., R. 39 E.
RANGE IN CHARACTERISTICS: Depth to the duripan is 20 to 40 inches. Depth to bedrock commonly is 40 to 60 inches. These soils are usually dry, but are moist during the winter and spring. The mean annual soil temperature is 47 to 50 degrees F. Organic matter content in the upper 9 inches is 1.5 to 2.5 percent. Rock fragments range form 5 to 25 percent in the solum and are common as a stone line on the surface of the 2Bt horizon.
The A horizon has value of 6 or 7 dry, 3 or 4 moist and chroma of 2 or 3 moist and dry.
The 2Bt horizon has value of 3 or 4 moist, 5 or 4 dry and chroma of 3 or 4 moist and dry. It is clay or silty clay and averages 48 to 60 percent clay. It increases in clay 15 percent or more within a vertical distance of 1 inch from its upper boundary. This horizon has moderate or strong prismatic structure parting to strong subangular or angular blocky.
The 2Btk horizon is silty clay loam, clay or stony clay. The depth to segregated or disseminated lime is about 15 to 30 inches.
The duripan is platy with weakly to strongly cemented soil material between indurated lenses. It has 10 to 25 percent stones, cobbles and gravel.
COMPETING SERIES: These are the Chilcott, Kepler, Lovejoy, and Reno series. Chilcott soils are greater than 60 inches deep to bedrock and have less than 5 percent rock fragments in the upper Bt horizon. Kepler soils have weakly to moderately cemented duripans and have an E horizon below and Ap horizon. Lovejoy soils are slightly to moderately acid above the duripan and have 35 to 45 percent clay in the argillic horizon. Reno soils are noncalcareous in the A and B horizons and have strongly cemented duripans with discontinuous indurated silica laminae.
GEOGRAPHIC SETTING: Lookout soils are on hills at elevations of 2,800 to 3,600 feet. Slopes are 0 to 45 percent. The soils formed in colluvium weathered from basalt with an influence of loess, volcanic ash and pumice in the surface horizon. The climate is semiarid and summers are dry. The mean annual temperature is 45 to 48 degrees F. The mean annual precipitation is 8 to 12 inches. The frost-free period is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ruckles and Virtue soils. Ruckles soils are clayey-skeletal and lack duripans. Virtue soils are fine-silty.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; slow permeability.
USE AND VEGETATION: Mainly rangeland. Small acreage is irrigated for alfalfa, hay, pasture and small grain. Native
vegetation dominantly is bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, buckwheat, and big sagebrush.
DISTRIBUTION AND EXTENT: Central and eastern Oregon. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Union County (Baker Area Survey), Oregon; 1945.
ADDITIONAL DATA: Characterization and engineering data on 2 profiles (S62-ORE-31-1 and S62-ORE-1-1) by OSU Lab on soils samples in Union and Baker Counties. Data not published.
NSTH 17, RECLASSIFICATION ONLY, 3/95