LOCATION DOUBLEO            OR
Established Series
Rev. TLC/TDT/JVC
07/1999

DOUBLEO SERIES


The Doubleo series consists of very deep, poorly drained soils that formed in alluvium over lacustrine deposits derived from igneous rock. Doubleo soils are on depressions of low stream terraces. Slopes are 0 to 2 percent. The mean annual precipitation is about 9 inches and the mean annual air temperature is about 44 degrees F.

TAXONOMIC CLASS: Clayey over loamy, smectitic over mixed, superactive, calcareous, frigid Fluvaquentic Vertic Endoaquolls

TYPICAL PEDON: Doubleo loam--on a 1 percent slope at an elevation of 4,115 feet--rangeland. (Colors are for dry soil unless otherwise noted.) A discontinuous mat of roots and some leaves is present in the upper inch of soil.

Ak--0 to 3 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine interstitial pores; strongly effervescent; few fine masses of secondary calcium carbonate; moderately alkaline (pH 8.4); clear wavy boundary. (3 to 10 inches thick)

Bk--3 to 10 inches; dark gray (10YR 4/1) silty clay, very dark gray (10YR 3/1) moist; moderate fine and very fine subangular blocky structure; hard, very firm, slightly sticky and very plastic; common very fine and fine and few coarse roots; few very fine tubular pores; slightly effervescent; few fine coats of secondary calcium carbonate on faces of peds; moderately alkaline (pH 8.4); clear wavy boundary. (4 to 10 inches thick)

Bkss--10 to 20 inches; dark grayish brown (10YR 4/2) clay, dark gray (10YR 4/1) moist; strong fine and medium subangular blocky structure; extremely hard, rigid, moderately sticky and very plastic; few very fine and fine roots; few very fine tubular pores; common distinct intersecting slickensides; slightly effervescent; common fine coats of secondary calcium carbonate on faces of peds; common fine prominent brown (7.5YR 4/4) moist masses of iron accumulation; moderately alkaline (pH 8.2); gradual wavy boundary. (7 to 14 inches thick)

B'k--20 to 28 inches; gray (10YR 5/1) clay loam, dark gray (10YR 4/1) moist; moderate fine and medium subangular blocky structure; very hard, extremely firm, moderately sticky and very plastic; very few very fine roots; common very fine tubular pores; strongly effervescent; common fine coats of secondary calcium carbonate on faces of peds; common fine prominent brown (7.5YR 4/4) moist masses of iron accumulation; moderately alkaline (pH 8.0); clear wavy boundary. (0 to 17 inches thick)

2C1--28 to 45 inches; light brownish gray (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, friable, nonsticky and nonplastic; very few very fine roots; common very fine tubular pores; slightly effervescent; common fine distinct brown (7.5YR 4/4) moist masses of iron accumulation; slightly alkaline (pH 7.8); gradual wavy boundary (10 to 17 inches thick)

2C2--45 to 60 inches; pale brown (10YR 6/3) loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, moderately sticky and slightly plastic; common very fine tubular pores; slightly effervescent; few medium distinct brown (7.5YR 4/4) moist masses of iron accumulation; slightly alkaline (pH 7.8).

TYPE LOCATION: Harney County, Oregon; about 3.5 miles south of the Malheur Field Station on the Center Patrol Road; 1,570 feet west and 2,350 feet south of the northeast corner of section 28, T. 27 S., R. 31 E.; USGS Coyote Buttes 7.5 minute topographic quadrangle; 43 degrees 11 minutes 29 seconds north latitude and 118 degrees 53 minutes 18 seconds west longitude, NAD27.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually wet in spring and early summer; a seasonal high water table is present from the soil surface to 2.5 feet from March through July; aquic moisture regime.

Mean annual soil temperature - 44 to 47 degrees F.

Mollic epipedon thickness - 10 to 20 inches.

Depth to major lithologic discontinuity of loamy material - 25 to 35 inches.

Particle-size control section - Clay content: 35 to 50 percent in the upper part and 10 to 20 percent in the lower part; Rock fragments: None.

Reaction - Slightly alkaline or moderately alkaline.

Calcium carbonate equivalent - 1 to 5 percent.

Redoximorphic features - Horizons having matrix chroma of 1, hue of 10YR, and distinct or prominent redox concentrations of iron are directly below the horizons constituting the mollic epipedon.

Other features - The lower part of the control section and substratum has an irregular decrease in organic matter.

A horizon - Value: 4 or 5 dry, 2 or 3 moist.

Chroma: 1 or 2, dry or moist.

Organic matter content: 4 to 8 percent.

Bk horizon - Texture: Silty clay or silty clay loam.

Clay content: 35 to 50 percent.

Organic matter content: 2 to 5 percent.

Vertic features: 5 to 10 millimeter wide cracks are open in late summer and early fall.

Bkss horizon - Texture: Clay or silty clay.

Clay content: 40 to 60 percent.

Organic matter content: 1 to 2 percent.

Vertic features: Short intersecting slickensides are present; 5 to 10 millimeter wide cracks are open in late summer and early fall.

B'k horizon (when present) - Texture: Clay loam or silty clay loam.

Clay content: 35 to 40 percent.

Organic matter content: 1 to 2 percent.

2C1 horizon - Value: 5 through 7 dry.

Texture: Fine sandy loam or silt loam.

Clay content: 5 to 15 percent.

Organic matter content: 0.5 to 1 percent.

2C2 horizon - Texture: Loam or silt loam.

Clay content: 15 to 20 percent.

Organic matter content: 0.2 to 1 percent.

COMPETING SERIES: At present, there are no other series in this family.

GEOGRAPHIC SETTING: Doubleo soils are on depressions of low stream terraces. These soils formed in alluvium over lacustrine deposits derived from igneous rocks. Slopes are 0 to 2 percent. Elevations range from 4,100 to 4,200 feet. The climate is characterized by cold, moist winters and hot, dry summers. The mean annual precipitation is 8 to 10 inches. The mean annual temperature is 43 to 45 degrees F. The frost-free period is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ausmus, Skidoosprings, Fury, Housefield, Mcbain, and Skunkfarm soils. Ausmus, Skidoosprings, and Mcbain soils are on adjacent high lake terraces and have ochric epipedons. Skunkfarm soils are on high stream terraces and are somewhat poorly drained. Housefield soils are on low stream terraces and are very poorly drained. Fury soils are fine-silty and are on adjacent high stream terraces.

DRAINAGE AND PERMEABILITY: Poorly drained; negligible surface runoff; very slow permeability in the upper part of the profile and moderately rapid permeability in the lower part. These soils are frequently ponded for long duration from March through July with water up to 1 foot deep.

USE AND VEGETATION: Doubleo soils are used for livestock grazing and wildlife habitat. The native vegetation is cattail and hardstem bullrush.

DISTRIBUTION AND EXTENT: Southeastern Oregon. These soils are not extensive with about 6,000 acres of the series mapped to date. MLRA 23.

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

SERIES ESTABLISHED: Harney County, Oregon 1997.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - The zone from the soil surface to 10 inches (Ak and Bk horizons).

Vertic features - The zone from 10 to 20 inches with intersecting slickensides and the zone from 3 to 20 inches with cracks over 5 millimeters in width (Bk and Bkss horizons).

Fluventic feature - The zone from 28 to 50 inches with an irregular decrease in organic-carbon content (2C1 and 2C2 horizons).

Aquic conditions - Endosaturation and iron reduction occur within 20 inches of the soil surface in most years.

Major lithologic discontinuity - The abrupt change to loamy material at about 28 inches (2C1 and 2C2 horizons).

A strongly contrasting particle-size class is within a depth of 40 inches.

Particle-size control section - The zone from 10 to 40 inches (Bkss and B'k horizons and part of the 2C1 horizon).


National Cooperative Soil Survey
U.S.A.