LOCATION WEGERT                  OR

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

WEGERT SERIES

The Wegert series consists of moderately deep, somewhat excessively drained soils that formed volcanic ash and pumice over residuum derived from basalt. Wegert soils are on lava plains and lava plateaus. Slopes are 0 to 15 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is 7 degrees C.

TAXONOMIC CLASS: Ashy, glassy, frigid Vitritorrandic Haploxerolls

TYPICAL PEDON: Wegert gravelly ashy loamy sand--on a nearly level plain at an elevation of about 1,345 meters--rangeland. (Colors are for dry soil unless otherwise noted. When described on May 18, 1994, the soil was dry throughout.)

A1--0 to 5 cm; dark grayish brown (10YR 4/2) gravelly ashy loamy sand, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; 50 percent very pale brown (10YR 7/3) medium through very coarse sand-size (0.25 to 2.0 mm diameter) pumiceous ash grains; 30 percent fine gravel; neutral (pH 7.0); clear smooth boundary.

A2--5 to 15 cm; dark grayish brown (10YR 4/2) ashy loamy sand, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; common very fine and fine roots, few medium, and coarse; common fine interstitial pores; 50 percent very pale brown (10YR 7/3) medium through very coarse sand-size (0.25 to 2.0 mm diameter) pumiceous ash grains; 10 percent fine gravel; neutral (pH 7.2); clear smooth boundary. (Combined thickness of the A horizons is 13 to 25 cm.)

Bw1--15 to 51 cm; brown (10YR 5/3) ashy loamy sand, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots, few medium and common fine interstitial pores; 40 percent very pale brown (10YR 7/3) medium through very coarse sand-size (0.25 to 2.0 mm diameter) pumiceous ash grains; 5 percent fine gravel; slightly alkaline (pH 7.4); clear smooth boundary. (18 to 36 cm thick)

Bw2--51 to 69 cm; pale brown (10YR 6/3) ashy sandy loam, dark brown (10YR 3/3) moist; moderate medium and coarse subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common very fine and fine roots; common fine tubular pores; 30 percent very pale brown (10YR 7/3) medium through very coarse sand-size (0.25 to 2.0 mm diameter) pumiceous ash grains; slightly alkaline (pH 7.6); clear smooth boundary. (15 to 30 cm thick)

2C--69 to 79 cm; pale brown (10YR 6/3) extremely cobbly ashy loamy sand, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, friable, nonsticky and nonplastic; few very fine and fine roots; few fine tubular pores; 30 percent very pale brown (10YR 7/3) medium through very coarse sand-size (0.25 to 2.0 mm diameter) pumiceous ash grains; 50 percent cobbles and 20 percent gravel; slightly alkaline (pH 7.8); clear smooth boundary. (8 to 18 cm thick)

2R--79 cm; basalt.

TYPE LOCATION: Lake County, Oregon; north of Fort Rock Valley and west of The Devils Garden lava field; approximately 200 feet west and 150 feet north of the southeast corner of section 31, T. 24 S., R. 15 E.; USGS Cougar Mountain 7.5 minute topographic quadrangle; latitude 43 degrees 26 minutes 34 seconds N and longitude 120 degrees 57 minutes 25 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section in winter and spring, dry in summer and fall; aridic moisture regime that borders on xeric.
Mean annual soil temperature7 to 8 degrees C.
Mollic epipedon thickness: 25 to 50 cm.
Depth to bedrock: 50 to 100 cm to a lithic contact.
Other features: Medium through very coarse sand-size (0.25 to 2.0 mm) pumiceous ash content of the A and Bw horizons ranges from 30 to 50 percent.

Particle-size control section - Clay content: averages 5 to 15 percent.
Volcanic glass content: 30 to 70 percent in coarse silt through very coarse sand fractions.

A1 horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 2 or 3 percent.

A2 horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Texture: Ashy loamy sand, ashy loamy fine sand, gravelly ashy loamy sand, or very cobbly ashy loamy fine sand.
Organic matter content: 2 or 3 percent.

Bw1 horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Texture: Ashy sandy loam or ashy loamy sand
Rock fragments: 0 to 15 percent fine gravel.
Organic matter content: 1 or 2 percent.

Bw2 horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Texture: Ashy sandy loam or ashy loamy sand.
Rock fragments: 0 to 10 percent fine gravel and 0 to 15 percent cobbles.
Other features: Pedons with texture of ashy loamy sand do not have cambic horizons.

2C horizon
Value: 6 or 7 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Texture: Extremely cobbly ashy loamy sand or very cobbly ashy loamy sand.
Rock fragments: 40 to 80 percent total with 0 to 25 percent gravel and 40 to 70 percent cobbles.

COMPETING SERIES: These are the Boltz, Bonnick, Borobey, Emamount, Embal, Frentera, Gardone, Oatmanflat, Picturerock, Stookmoor, and Tuffcabin series.

Boltz soils are moderately deep to paralithic contacts. Bonnick, Borobey, Emamount, Embal, Gardone, and Picturerock soils are very deep. Frentera soils do not have ashy sandy textures in the particle-size control section and do not have subhorizons above the lithic contact with greater than 40 percent rock fragments. Stookmoor soils have firm, brittle horizons, do not have ashy sandy textures in the particle-size control section, and do not have subhorizons above the lithic contact with greater than 40 percent rock fragments. Oatmanflat and Tuffcabin soils are deep to buried duripans.

GEOGRAPHIC SETTING: Wegert soils are on lava plains and lava plateaus. These soils formed in volcanic ash and pumice over residuum derived from basalt. Much of the volcanic ash is from ancestral Mt. Mazama. Slopes are 0 to 15 percent. Elevations range from 1,310 to 1,630 meters. The climate is semiarid with cold, moist winters and warm, dry summers. The mean annual precipitation is 200 to 300 mm, the mean annual temperature is 6 to 7 degrees C, and the frost-free period is 40 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bonnick, Fort Rock, Henkle, Kunceider, and Wanoga soils. Bonnick and Fort Rock are very deep. Henkle and Kunceider soils are shallow over bedrock. Wanoga soils have andic properties.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat excessively drained; medium or high surface runoff; high saturated hydraulic conductivity.

USE AND VEGETATION: Wegert soils are used for irrigated cropland, livestock grazing, and wildlife habitat. Alfalfa hay and barley are the principal crops. The vegetation in rangeland is mainly mountain big sagebrush, needleandthread, Ross sedge, Indian ricegrass, and basin wildrye.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are moderately extensive. MLRA 23.

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

SERIES ESTABLISHED: Lake County (Northern Part), Oregon, 2006. The name is from a well.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 51 cm (A1, A2, and Bw1 horizons).
Cambic horizon - The zone from 51 to 69 cm (Bw2 horizon).
Vitrandic intergrade feature - The zone from the soil surface to 76 cm (A1, A2, Bw1, and Bw2 horizons and part of the 2C horizon).
Lithic contact - The boundary at 79 cm to underlying hard bedrock (2R layer).
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from 25 to 79 cm (Bw2 and 2C horizons and part of the Bw1 horizon).

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National Cooperative Soil Survey
U.S.A.