LOCATION MOONBEAM                OR

Established Series
Rev. CWL-MPK-JVC
04/2011

MOONBEAM SERIES

The Moonbeam series consists of shallow to a duripan, well drained soils that formed in volcanic ash over residuum derived from basalt. Moonbeam soils are on lava plateaus. Slopes are 0 to 20 percent. The mean annual precipitation is about 280 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Clayey, smectitic, frigid, shallow Vitritorrandic Durixerolls

TYPICAL PEDON: Moonbeam very cobbly ashy loam--on the summit of a lava plateau sloping 1 percent to the south at an elevation of 1,448 meters--rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; grayish brown (10YR 5/2) very cobbly ashy loam, dark brown (10YR 3/3) moist; moderate very thick platy structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and common fine roots; common very fine, common fine, and few medium vesicular pores; 25 percent gravel, 10 percent cobbles, and 4 percent stones; slightly alkaline (pH 7.6); abrupt smooth boundary. (5 or 8 cm thick)

A2--8 to 20 cm; grayish brown (10YR 5/2) gravelly ashy sandy clay loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, many fine, and few medium roots; common very fine and common fine vesicular and tubular pores; 15 percent gravel and 4 percent cobbles; slightly alkaline (pH 7.7); abrupt smooth boundary. (13 to 20 cm thick)

2Bt1--20 to 36 cm; light brown (7.5YR 6/3) clay, brown (7.5YR 4/3) moist; strong medium prismatic structure parting to strong medium angular blocky; very hard, friable; moderately sticky and very plastic; few very fine, few fine, and few medium roots; few very fine tubular pores; common faint and few distinct clay films on faces of peds; slightly alkaline (pH 7.8); clear smooth boundary. (10 to 15 cm thick)

2Bt2--36 to 46 cm; light brown (7.5YR 6/3) clay, brown (7.5YR 4/3) moist; moderate medium subangular blocky structure parting to strong fine angular blocky; hard, firm, moderately sticky and very plastic; few very fine, few fine, and few medium roots; few very fine tubular pores; common distinct clay films on faces of peds; moderately alkaline (pH 8.0); abrupt smooth boundary. (10 to 15 cm thick)

2Bqkm--46 to 69 cm; very pale brown (10YR 8/2) cemented material, light yellowish brown (10YR 6/4) moist; strong very thick platy structure; very rigid, indurated by secondary silica; widely spaced fractures in the upper part of horizon; secondary carbonates segregated as few medium coats on bottoms of peds; strongly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (8 to 28 cm thick)

2R--69 cm; basalt.

TYPE LOCATION: Lake County, Oregon; about 1 mile northwest of Chicago Valley Well; approximately 1,100 feet south and 2,400 feet west of the northeast corner of section 13, T. 24 S., R. 20 E.; USGS Moonlight Butte 7.5 minute topographic quadrangle; latitude 43 degrees 29 minutes 47 seconds N and longitude 120 degrees 15 minutes 49 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry in summer and fall; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 20 to 30 cm; includes part of the argillic horizon in some pedons.
Depth to duripan: 33 to 50 cm.
Depth to bedrock: 50 to 100 cm to a lithic contact.
Vitrandic intergrade properties: Occurs in horizons from the soil surface to at least 18 cm in depth within horizons having clay content of less than about 40 percent.

Particle-size control section - Clay content: 35 to 50 percent;
Rock fragments: 0 to 20 percent. Lithology of fragments are basalt or detached indurated fragments of duripan.

A1 horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 to 3 percent.
Reaction: Neutral or slightly alkaline
Volcanic glass content: 20 to 65 percent in coarse silt through fine sand fractions.
Oxalate extractable aluminum plus one-half oxalate iron: 0.2 to 0.4 percent.

A2 horizon
Value: 4 or 5 dry.
Chroma: 2 or 3, dry or moist.
Texture: Ashy sandy clay loam, gravelly ashy sandy clay loam, ashy fine sandy loam, or cobbly ashy fine sandy loam.
Clay content: 16 to 25 percent.
Rock fragments: 10 to 25 percent.
Reaction: Neutral or slightly alkaline.
Organic matter content: 1 or 2 percent.
Volcanic glass content: 20 to 65 percent in coarse silt through fine sand fractions.
Oxalate extractable aluminum plus one-half oxalate iron: 0.2 to 0.4 percent.

2Bt1 horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4 dry and moist.
Texture: Mainly clay or clay loam; some pedons have texture of ashy clay loam.
Clay content: 35 to 50 percent.
Rock fragments: 0 to 15 percent, with 0 to 10 percent gravel and 0 to 10 percent cobbles.
Volcanic glass content: 15 to 30 percent in coarse silt through fine sand fractions.
Oxalate extractable aluminum plus one-half oxalate iron: 0.2 to 0.4 percent.

2Bt2 horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Texture: Clay or cobbly clay.
Clay content: 40 to 50 percent.
Rock fragments: 0 to 20 percent, with 0 to 10 percent gravel and 0 to 15 percent cobbles
Reaction: Slightly alkaline or moderately alkaline.

2Bqkm horizon
Hue: 10YR or 7.5YR.
Value: 6 through 8 dry, 4 through 6 moist.
Chroma: 2 through 4 moist.
Cementation: Very strongly cemented or indurated.

COMPETING SERIES: This is the Mopana series. Mopana soils do not have lithic contacts within 150 cm of the soil surface and are intermittently moist in the upper horizons due to summer convection storms.

GEOGRAPHIC SETTING: Moonbeam soils are on lava plateaus. They typically occur on summit positions. These soils formed in volcanic ash over residuum derived from basalt. Slopes are 0 to 20 percent. Elevations range from 1,250 to 1,830 meters. The climate is semiarid and characterized by cold, moist winters and warm, dry summers. The mean annual precipitation is 230 to 300 mm, but ranges to 400 mm in some areas. The mean annual temperature is 6 to 7 degrees C, and the frost-free period is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hayespring, Oatmanflat, Senra, and Sliptrack soils. Oatmanflat soils are ashy and deep to buried duripans. Hayespring and Sliptrack soils are moderately deep to duripans. Senra soils are ashy and have 27 to 35 percent clay in the particle-size control section.

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

USE AND VEGETATION: Moonbeam soils are used for livestock grazing and wildlife habitat. The vegetation is low sagebrush, Idaho fescue, Thurber's needlegrass, and western juniper.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are extensive with about 123,000 acres of the series mapped to date. MLRA 23.

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

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

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 20 cm (A1 and A2 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 20 cm (A1 and A2 horizons).
Argillic horizon - The zone from 20 to 46 cm (Bt1 and Bt2 horizons).
Duripan - The zone from 46 to 69 cm (Bqkm horizon).
Identifiable secondary carbonates - The zone from 46 to 69 cm (Bqkm horizon).
Lithic contact - The boundary at 69 cm to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 20 to 46 cm (Bt1 and Bt2 horizons).

ADDITIONAL DATA: Volcanic glass content determined locally by optical grain counts using a polarizing petrographic microscope. Oxalate extractable aluminum plus one-half oxalate extractable iron values are estimated.

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National Cooperative Soil Survey
U.S.A.