LOCATION OUTERKIRK OR+NV

Established Series
Rev: RDK-TDT-RWL-JBF
11/2010

OUTERKIRK SERIES

The Outerkirk series consists of very deep, well drained soils that formed in mixed alluvium. Outerkirk soils are on alluvial fans and basin floors and have slopes of 1 to 6 percent. The mean annual precipitation is about 200 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Durinodic Haplocalcids

TYPICAL PEDON: Outerkirk sandy loam on a 3 percent slope, rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 15 cm; light brownish gray (10YR 6/2) sandy loam, dark brown (10YR 3/3) moist; moderate coarse platy structure; slightly hard, friable, nonsticky and nonplastic; common very fine, fine and medium roots; many very fine and fine vesicular pores; slightly effervescent-calcium carbonate is 1 percent; 5 percent gravel; moderately alkaline (pH 8.4); clear wavy boundary. (8 to 20 cm thick)

Bk1--15 to 58 cm; light gray (10YR 7/2) sandy loam, dark yellowish brown (10YR 3/4) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and nonplastic; common very fine, fine and medium roots; many very fine vesicular and irregular pores; strongly effervescent-calcium carbonate is 4 percent; strongly alkaline (pH 8.8); clear smooth boundary. (28 to 56 cm thick)

Bk2--58 to 74 cm; pale brown (10YR 6/3) gravelly sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, friable, nonsticky and nonplastic; few very fine and fine roots; many very fine irregular pores; violently effervescent-calcium carbonate is 5 percent; 20 percent gravel; strongly alkaline (pH 8.8); clear smooth boundary. (15 to 25 cm thick)

Bkq--74 to 130 cm; very pale brown (10YR 7/3) loamy sand, dark yellowish brown (10YR 3/4) moist; massive; hard, firm, nonsticky and nonplastic; few very fine and fine roots; many very fine irregular pores; 40 percent durinodes; violently effervescent-disseminated lime; strongly alkaline (pH 8.6); clear smooth boundary. (38 to 76 cm thick)

2C--130 to 152 cm; brown (10YR 5/3) loamy sand, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine irregular pores; calcium-carbonate is trace; 10 percent gravel; strongly alkaline (pH 8.6).

TYPE LOCATION: Harney County, Oregon; about 2 miles east of Fields and 300 feet north of trail in the SW1/4NW1/4 section 20, T. 38 S., R. 35 E.; latitude 42 degrees 15 minutes 45 seconds N and longitude 118 degrees 38 minutes 21 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil Moisture: Usually dry; intermittently moist in the winter and spring; typic aridic soil moisture regime.
Mean annual soil temperature: 8 to 10 degrees C.
Depth to durinodes: 50 to 100 cm.
Depth to secondary carbonates: 8 to 20 cm.
Depth to the calcic horizon (Bk2): 36 to 64 cm.

Particle-size control section - Clay content: 5 to 15 percent.
Sand: More than 15 percent coarser than very fine sand.
Rock fragments: 0 to 20 percent, gravel

A horizon
Value: 5 to 7 dry, 2 or 3 moist.
Chroma: 2 or 3 moist and dry.
Organic matter: 0.5 to 0.8 percent.

Bk horizon
Value: 6 or 7 dry, 2 or 3 moist.
Chroma: 2 through 4, moist and dry.
Calcium carbonate: 4 to 8 percent.
Other features: strongly or violently effervescent.

2Bkq horizon
Texture: sandy loam or loamy sand.
Calcium carbonate: 4 to 8 percent.
Durinodes: 20 to 50 percent
Consistance: Continuously hard, firm and brittle in some pedons.

2C horizon
Texture: Loamy sand, sandy loam or silty clay loam.

COMPETING SERIES: These are the Caphor and Hardhat series.

Cahpor soils have a 2Ck horizon with 25 to 50 percent gravel. Hardhat soils have a gypsum at 30 to 64 cm.

GEOGRAPHIC SETTING: Outerkirk soils are on alluvial fans and on basin floors at elevations of 1,100 to 1,400 meters. Slopes are 1 to 6 percent. The soils formed in alluvium derived from mixed rocks. The climate is characterized by cold dry winters and warm dry summers. The mean annual precipitation is 150 to 250 mm. The mean annual temperature is 7 to 9 degrees C. The frost-free period is 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Catlow, Defenbaugh, Deppy, Dixon and Tumtum soils. Catlow soils are loamy-skeletal. Defenbaugh soils have a fine-loamy particle-size control section. Deppy and Tumtum soils have an argillic horizon and are shallow over a duripan. Dixon soils have a fine-loamy over sandy or sandy-skeletal particle-size control section.

DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: The soils are used for livestock grazing. The potential native vegetation is big sagebrush, black greasewood, spiny hopsage, Indian ricegrass and basin wildrye.

DISTRIBUTION AND EXTENT: Southeastern Oregon, and Northwestern Nevada; MLRA 24. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Humboldt County, Western Part, Nevada, 1993.

REMARKS: Diagnostic horizons and features included in this pedon are:
Ochric epipedon - The zone from the surface to 18 cm (A and part Bk1 horizons).
Calcic horizon - The zone from 58 to 74 cm (Bk2 horizon).
Durinodic intergrade - from 74 to 130 cm (2Bkq horizon) contains 40 percent durinodes.
Particle-size control section - The zone from 25 to 100 cm (Bk2 and part of the Bk1 and 2Bkq horizons).

ADDITIONAL DATA: Reference sample S82OR-025-001; Sample Nos. 73-76.

National Cooperative Soil Survey
U.S.A.