LOCATION BOILOUT                 OR

Established Series
Rev. CWL-MPK-JVC-JBF
11/2010

BOILOUT SERIES

The Boilout series consists of shallow to a duripan, well drained soils that formed in eolian volcanic ash over residuum derived from basalt and tuff. Boilout soils are on lava plateaus and hills. Slopes are 2 to 10 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Ashy, glassy, mesic, shallow Vitrixerandic Argidurids

TYPICAL PEDON: Boilout cobbly ashy fine sandy loam--on the nearly level summit of a plateau at an elevation of 4,555 feet--rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; grayish brown (10YR 5/2) cobbly ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak thick platy structure parting to moderate medium granular; soft, very friable, nonsticky and nonplastic; many very fine, common fine roots; many very fine, common fine and few medium interstitial and tubular pores; 10 percent gravel, 10 percent cobbles, and 3 percent stones; slightly alkaline (pH 7.6); abrupt smooth boundary. (5 to 10 cm thick)

A2--8 to 15 cm; light brownish gray (10YR 6/2) cobbly ashy very fine sandy loam, dark grayish brown (10YR 4/2) moist; strong thick platy structure parting to weak medium subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine, common fine, and few medium vesicular pores; 5 percent gravel, 10 percent cobbles, and 2 percent stones; slightly alkaline (pH 7.7); abrupt smooth boundary. (8 to 15 cm thick)

Btq1--15 to 23 cm; pale brown (10YR 6/3) ashy clay loam, brown (10YR 4/3) moist; strong medium platy structure parting to moderate medium subangular blocky; hard, firm, moderately sticky and moderately plastic; common very fine and few fine roots; common very fine, few fine, and few medium tubular pores; common distinct opal coats on faces of peds; common distinct clay films on faces of peds; 5 percent gravel; slightly alkaline (pH 7.8); abrupt smooth boundary. (8 to 20 cm thick)

Btq2--23 to 28 cm; light brown (7.5YR 6/4) ashy clay loam, brown (7.5YR 4/4) moist; moderate medium platy structure parting to strong fine subangular blocky; hard, firm, moderately sticky and moderately plastic; few very fine and few fine roots; few very fine and few fine tubular pores; common distinct opal coats on faces of peds; common distinct clay films on faces of peds; moderately alkaline (pH 7.9); abrupt smooth boundary. (0 to 15 cm thick)

Bqk--28 to 41 cm; very pale brown (10YR 7/4) extremely paragravelly ashy loam, yellowish brown (10YR 5/4) moist; moderate medium platy structure parting to strong fine angular blocky; very hard, very firm, slightly sticky and slightly plastic; common very fine, few fine, few medium, and few coarse roots; slightly effervescent; few faint opal coats on faces of peds; secondary carbonates segregated as few fine coats on duripan fragments; 80 percent moderately cemented duripan parafragments; moderately alkaline (pH 7.9); abrupt smooth boundary. (0 to 13 cm thick)

Bqkm1--41 to 86 cm; very pale brown (10YR 8/4) cemented material, light yellowish brown (10YR 6/4) moist; strong medium and thick platy structure parting to strong fine and medium angular blocky; extremely hard, very firm; moderately cemented by secondary silica; secondary carbonates segregated as few medium coats on bottoms of peds; strongly effervescent; moderately alkaline (pH 8.0); clear smooth boundary. (10 to 46 cm thick)

Bqkm2--86 to 150 cm; very pale brown (10YR 8/2) cemented material, light brownish gray (10YR 6/2) and very pale brown (10YR 7/4) moist; strong very thick platy structure; very rigid; indurated by secondary silica; secondary carbonates segregated as few medium coats on bottoms of peds; strongly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (15 to 64 cm thick)

Bqkm3--150 to 157 cm; very pale brown (10YR 8/3) cemented material, light yellowish brown (10YR 6/4) moist; strong medium platy structure; rigid; very strongly cemented by secondary silica; secondary carbonates segregated as few medium coats on bottoms of peds; strongly effervescent; moderately alkaline (pH 8.2). (6 to 25 cm thick)

TYPE LOCATION: Lake County, Oregon; about 1 mile east of Burma Rim and 0.5 mile north of South Buffalo Waterhole; approximately 1,450 feet south and 2,500 feet west of the northeast corner of section 32, T. 27 S., R. 20 E.; USGS Buffalo Well 7.5 minute topographic quadrangle; latitude 43 degrees 11 minutes 23 seconds N and longitude 120 degrees 20 minutes 44 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: 8 to 10 degrees C.
Ochric epipedon thickness: 13 to 20 cm.
Depth to base of argillic horizon: 36 to 50 cm.
Depth to duripan: 36 to 50 cm.
Duripan thickness: 60 to 140 cm.
Depth to bedrock - More than 150 cm.

Particle-size control section - Clay content: 20 to 32 percent.
Rock fragments: 0 to 10 percent, mainly gravel. Lithology of fragments are volcanic rocks such as basalt or tuff.

A1 horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Volcanic glass: Volcanic glass is estimated to range from 20 to 50 percent of the 0.2 to 2 mm fraction.

A2 horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Clay content: 10 to 18 percent.
Rock fragments: 10 to 20 percent.
Texture: Cobbly ashy very fine sandy loam, gravelly ashy very fine sandy loam, or ashy very fine sandy loam.
Volcanic glass: Volcanic glass is estimated to range from 20 to 50 percent of the 0.2 to 2 mm fraction.


Btq1 horizon
Hue: 10YR or 7.5YR.
Chroma: 2 or 3, dry or moist.
Clay content: 20 to 32 percent.
Texture: Ashy loam or ashy clay loam.
Reaction: Slightly alkaline or moderately alkaline.

Btq2 horizon
Chroma: 3 or 4, dry or moist.
Clay content: 28 to 32 percent.
Reaction: Slightly alkaline or moderately alkaline.
Volcanic glass: Volcanic glass is estimated to range from 5 to 25 percent of the 0.2 to 2 mm fraction.

Bqk horizon (when present)
Pararock fragments: 35 to 80 percent weakly cemented or moderately cemented, weathered duripan parafragments.
Calcium carbonate equivalent: 1 to 3 percent.
Volcanic glass: Volcanic glass is estimated to range from 5 to 25 percent of the 0.2 to 2 mm fraction.

Bqkm horizons
Hue: 10YR or 7.5YR.
Value: 7 or 8 dry, 5 or 6 moist.
Chroma: 2 through 4, dry or moist.
Cementation: Moderately cemented to indurated; Indurated in at least one subhorizon.
Rock fragments: 0 to 40 percent.

COMPETING SERIES: There are no other series in this family.

GEOGRAPHIC SETTING: Boilout soils are on lava plateaus and hills. These soils formed in eolian material with a high content of volcanic ash over residuum derived from basalt or tuff. Slopes are 2 to 10 percent. Elevations range from 1,310 to 1,505 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm, mean annual temperature is 7 to 9 degrees C., and the frost-free period is 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brace, Rabbithills, and Raz soils. Brace soils are fine-loamy and are moderately deep to thin duripans overlying lithic contacts. Rabbithills soils are loamy, have cambic horizons, and have thin, strongly cemented duripans. Raz soils are loamy and are shallow to thin duripans overlying lithic contacts.

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

USE AND VEGETATION: Boilout soils are used for livestock grazing. The vegetation is basin big sagebrush, Thurber's needlegrass, Indian ricegrass, and bluebunch wheatgrass.

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 local waterhole.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 15 cm (A1 and A2 horizons).
Argillic horizon - The zone from 15 to 28 cm (Btq1 and Btq2 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 41 cm (A1, A2, Btq1, Btq2, and Bqk horizons).
Duripan - The zone from 41 to 157 cm (Bqkm1, Bqkm2, and Bqkm3 horizons)
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from 15 to 28 cm (Btq1 and Btq2 horizons).

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National Cooperative Soil Survey
U.S.A.