LOCATION DEVAUL OR
Tentative Series
Rev. CWL-JVC
12/2022
DEVAUL SERIES
The Devaul series consists of deep, well drained soils that formed in alluvium derived from basalt and tuff. Devaul soils are on plateaus. Slopes are 2 to 15 percent. The mean annual precipitation is about 18 inches and the mean annual temperature is about 44 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Argixerolls
TYPICAL PEDON: Devaul cobbly loam--on a 3 percent slope at an elevation of 4,960 feet--rangeland. (Colors are for dry soil unless otherwise noted. The soil was dry throughout when it was described on November 5, 1997.)
A1--0 to 3 inches; grayish brown (10YR 5/2) cobbly loam, very dark grayish brown (10YR 3/2) moist; moderate medium platy structure parting to moderate medium granular; soft, very friable, slightly sticky and slightly plastic; common very fine, few fine, few medium, and few coarse roots; common fine and medium interstitial and tubular pores; 15 percent pebbles and 12 percent cobbles; neutral (pH 7.0); abrupt smooth boundary. (2 to 4 inches thick)
A2--3 to 12 inches; grayish brown (10YR 5/2) cobbly loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure parting to moderate medium granular; slightly hard, friable, slightly sticky and slightly plastic; common very fine, common fine, common medium, and few coarse roots; common fine and medium interstitial and tubular pores; 15 percent pebbles and 12 percent cobbles; neutral (pH 7.2); clear smooth boundary. (8 to 16 inches thick)
Bt1--12 to 18 inches; brown (10YR 5/3) cobbly clay loam, dark yellowish brown (10YR 3/4) moist; strong medium subangular blocky structure parting to weak fine angular blocky; slightly hard, firm, moderately sticky and moderately plastic; few very fine, common fine, common medium, and few coarse roots; common medium tubular pores; common faint clay films on faces of peds; 15 percent pebbles and 15 percent cobbles; neutral (pH 7.3); clear smooth boundary. (6 to 15 inches thick)
Bt2--18 to 33 inches; yellowish brown (10YR 5/4) very cobbly clay loam, brown (10YR 4/3) moist; moderate medium angular blocky structure; hard, firm, moderately sticky and moderately plastic; few very fine, few fine, and few medium roots; common fine and medium interstitial and tubular pores; common faint and few distinct clay films on faces of peds; 20 percent pebbles and 20 percent cobbles; slightly alkaline (pH 7.4); clear smooth boundary. (8 to 16 inches thick)
Bt3--33 to 42 inches; brown (7.5YR 5/4) very cobbly clay loam, brown (7.5YR 4/3) moist; strong medium angular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine tubular pores; common distinct clay films on faces of peds; 20 percent pebbles and 20 percent cobbles; slightly alkaline (pH 7.5); gradual wavy boundary. (6 to 10 inches thick)
Bt4--42 to 56 inches; light brown (7.5YR 6/3) very cobbly clay loam, brown (7.5YR 4/4) moist; strong medium angular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine tubular pores; common faint and common distinct clay films on faces of peds; 20 percent pebbles and 20 percent cobbles; slightly alkaline (pH 7.5); gradual wavy boundary. (0 to 20 inches thick)
2Cr--56 to 62 inches; pink (7.5YR 7/3) weathered ash-flow tuff, strong brown (7.5YR 4/6) moist.
TYPE LOCATION: Klamath County, Oregon; about 1 mile east of Gerber Reservoir, 0.5 mile north of Casebeer Spring, and 100 yards east of the CCC road; 2,400 feet south and 1,400 feet east of the northwest corner of section 4, T. 39 S., R. 14 E.; USGS Gerber Reservoir 7.5 minute topographic quadrangle; 42 degrees 13 minutes 02 seconds north latitude and 121 degrees 04 minutes 14 seconds west longitude, NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in winter and spring, dry in summer and fall; xeric moisture regime that borders on aridic.
Mean annual soil temperature - 45 to 47 degrees F.
Mean summer soil temperature - 59 to 61 degrees F.
Mollic epipedon thickness - 10 to 18 inches.
Argillic horizon thickness - 18 to 30 inches.
Depth to base of argillic horizon - 40 to 50 inches.
Depth to bedrock - 45 to 60 inches to a paralithic contact. The paralithic materials below the contact are weathered basalt or tuff.
Particle-size control section - Clay content: 30 to 35 percent; Rock fragments: 35 to 45 percent, mainly pebbles and cobbles. Lithology of fragments are basalt and tuff.
A horizons - Chroma: 2 or 3, dry or moist.
Clay content: 20 to 27 percent.
Rock fragments: 20 to 35 percent.
Reaction: Slightly acid or neutral.
Organic matter content: 2 to 6 percent.
Bt1 horizon - Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Clay content: 28 to 35 percent.
Rock fragments: 25 to 35 percent.
Reaction: Slightly acid to slightly alkaline.
Bt2, Bt3, and Bt4 horizons - Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Clay content: 32 to 40 percent.
Rock fragments: 35 to 50 percent.
Reaction: Slightly acid to slightly alkaline.
COMPETING SERIES: These are the
Clanalpine,
Heechee,
Holmes,
Horrocks,
Hoskin,
Howcan (T),
Pequop,
Moreypeak,
Suak,
Valmar,
Vitale, and
Wambolt (T) series.
Clanalpine and
Moreypeak soils are moderately deep to paralithic contacts.
Heechee,
Holmes,
Howcan,
Pequop, and
Wambolt soils are very deep.
Horrocks soils are deep to lithic contacts and have the base of the argillic within 14 to 40 inches.
Hoskin,
Suak,
Valmar, and
Vitale soils are moderately deep to lithic contacts.
GEOGRAPHIC SETTING: Devaul soils are on plateaus. They typically occur on toeslope positions. These soils formed in alluvium derived from basalt and tuff. Slopes are 2 to 15 percent. Elevations range from 4,800 to 5,100 feet. The climate is characterized by cold, wet winters and warm, dry summers. The mean annual precipitation is 17 to 20 inches. The mean annual temperature is 43 to 45 degrees F., mean January temperature is 25 to 28 degrees F., and the mean July temperature is 56 to 60 degrees F. The frost-free period is 50 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Casebeer,
Dranket, and
Norcross soils. Casebeer and Norcross soils are clayey, shallow to duripans over bedrock, and have argillic horizons. Dranket soils are fine, moderately deep to duripans over bedrock, and have argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium or high surface runoff; moderately slow permeability.
USE AND VEGETATION: Devaul soils are used for livestock grazing, wildlife habitat, and recreation. The native vegetation is Idaho fescue, bluebunch wheatgrass, mountain big sagebrush, antelope bitterbrush, and western juniper.
DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive. MLRA 21.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES PROPOSED: Klamath County (Gerber Block of Fremont National Forest Area), Oregon, 1997. The name is from a lake in the area.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 12 inches (A1 and A2 horizons).
Argillic horizon - The zone from 12 to 56 inches (Bt1, Bt2, Bt3, and Bt4 horizons).
Paralithic contact - The boundary at 56 inches to underlying soft, weathered bedrock (2Cr layer).
Particle-size control section - The zone from 12 to 32 inches (Bt1 horizon and most of the Bt2 horizon).
National Cooperative Soil Survey
U.S.A.