LOCATION WILDHILL                OR

Established Series
Rev. RJK-TDT-JVC-JBF
06/2011

WILDHILL SERIES

The Wildhill series consists of moderately deep, well drained soils that formed in eolian deposits derived from mixed rocks over reworked alluvium and colluvium derived from basalt. Wildhill soils are on bedrock-controlled lake terraces. Slopes are 2 to 60 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Durinodic Xeric Haplargids

TYPICAL PEDON: Wildhill very stony loam--on a southwest-facing slope of less than 30 percent--rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 15 cm; light brownish gray (10YR 6/2) very stony loam, brown (10YR 5/3) moist; moderate thick platy structure; slightly hard, friable, slightly sticky and nonplastic; common fine and few medium roots; common fine irregular pores; 15 percent gravel, 25 percent cobbles, and 15 percent stones; moderately alkaline (pH 7.9); clear wavy boundary. (8 to 23 cm thick)

Btkn--15 to 48 cm; very pale brown (10YR 7/3) extremely stony loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and few medium roots; common fine irregular pores; few faint clay films on faces of peds; 25 percent gravel, 30 percent cobbles, and 20 percent stones; slightly effervescent; carbonates are disseminated; strongly alkaline (pH 8.5); clear wavy boundary. (25 to 58 cm thick)

Btkqn--48 to 66 cm; very pale brown (10YR 7/3) extremely gravelly loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; hard, firm and brittle, nonsticky and nonplastic; few fine roots; few fine irregular pores; few faint clay films on faces of peds; 60 percent gravel and 15 percent cobbles; strongly effervescent; secondary carbonates segregated as few fine irregularly shaped masses; strongly alkaline (pH 8.5); abrupt wavy boundary. (18 to 30 cm thick)

2R--66 cm; basalt.

TYPE LOCATION: Lake County, Oregon; north of Coleman Valley about 0.75 miles east of Spanish Lake; about 500 feet east of a jeep trail in the NE1/4 of the NE1/4 of the SE1/4 of section 21, T. 40 S., R. 25 E.; USGS Coleman Lake 7.5 minute topographic quadrangle; approximately latitude 42 degrees 05 minutes 03 seconds N and longitude 119 degrees 46 minutes 17 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the winter and spring, dry throughout the profile from about mid-June through October; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 9 to 11 degrees C.
Depth to horizon with firm consistence and a brittle manner of failure: 38 to 76 cm.
Depth to base of argillic horizon: 50 to 100 cm.
Depth to bedrock: 50 to 100 cm to a lithic contact.
Reaction: Moderately alkaline or strongly alkaline.

Particle-size control section - Clay content: 20 to 35 percent.
Rock fragments: Averages 40 to 75 percent. Lithology of fragments is basalt.

A horizon
Value: 5 or 6 dry, 3 through 5 moist.
Chroma: 2 through 4, dry or moist.

Btn or Btkn horizon
Value: 6 or 7 dry.
Chroma: 3 or 4, dry or moist.
Texture: Extremely stony loam, very cobbly clay loam, very cobbly sandy clay loam, or extremely cobbly clay loam.
Clay content: 20 to 35 percent.
Sodicity (SAR): 10 to 30.
Salinity (EC): 0 to 2 mmhos/cm.
Calcium carbonate equivalent: 0 to 2 percent.
Other features: The horizon lacks the prismatic or columnar structure definitive of a natric horizon.

Btkqn horizon
Value: 6 or 7 dry.
Chroma: 3 or 4, dry or moist.
Texture: Extremely cobbly loam, extremely gravelly loam, very cobbly sandy clay loam, or very cobbly clay loam.
Clay content: 20 to 30 percent.
Sodicity (SAR): 5 to 30.
Calcium carbonate equivalent: 1 or 2 percent.

COMPETING SERIES: These are the Broncho, Malaga, McConnel, McWatt, and Ragnel series.

The Broncho, Malaga, McConnel, McWatt and Ragnel soils are deeper than 100 cm.

GEOGRAPHIC SETTING: Wildhill soils are on bedrock-controlled lake terraces in Pleistocene lake basins. They formed in eolian deposits derived from mixed rocks over reworked alluvium and colluvium derived from basalt. These soils occur downwind of a salty playa (Summer Lake) and frequently receive new deposits of loess high in sodium salts. Slopes are 2 to 60 percent. Elevations range from 1,290 to 1,880 meters. The climate is semiarid and characterized by cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm, the mean annual temperature is 8 to 9 degrees C, and the frost-free period is 80 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: This is the McNye soil. McNye soils are sandy-skeletal, deep to lithic contacts, and have cambic horizons.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high or very high surface runoff; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Wildhill soils are used for livestock grazing and wildlife habitat. The potential native plant community is dominated by shadscale, bud sagebrush, Indian ricegrass, and spiny hopsage with scattered Wyoming big sagebrush.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive with about 6,500 acres of the series mapped to date. MLRA 23.

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

SERIES ESTABLISHED: Lake County (Southern Part), Oregon, 1991.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 15 cm (A horizon).
Argillic horizon - The zone from 15 to 66 cm (Btkn and Btkqn horizons).
Duric feature and identifiable secondary carbonates - The zone from 48 to 66 cm (Btkqn horizon).
Lithic contact - The boundary at 66 cm to underlying unweathered bedrock (2R layer).
Particle-size control section - The zone from 15 to 66 cm (Btkn and Btkqn horizons).

ADDITIONAL DATA: The typical pedon at the series type location is reference sampled by the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S88OR-037-001 (pedon # 88P0157). Selected data are available.

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National Cooperative Soil Survey
U.S.A.