LOCATION WISHER             OR
Tentative Series
Rev. SBF/ARR/TM
03/2008

WISHER SERIES


The Wisher series consists of very deep, well drained soils that formed in volcanic ash and loess over old mixed alluvium. Wisher soils are on stream terraces. Slopes are 2 to 15 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Vitritorrandic Argixerolls

TYPICAL PEDON: Wisher ashy silty clay loam, at an elevation of 1,180 meters, cropland. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 12 cm; brown (10YR 5/3) ashy silty clay loam, dark brown (10YR 3/3) moist; strong medium granular structure, slightly hard, friable, slightly sticky, slightly plastic; common fine and very fine roots; many very fine interstitial pores; neutral (pH 7.2). (6 to 20 cm thick)

Bt1--12 to 25 cm; brown (10YR 5/3) ashy silty clay loam, dark brown (10YR 3/3) moist; strong coarse subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; common fine and very fine roots; common fine and medium tubular and many very fine interstitial pores; 40 percent distinct pressure faces; slightly alkaline (pH 7.4). (7 to 67 cm thick)

Bt2--25 to 73 cm; yellowish brown (10YR 5/4) ashy silty clay loam, dark grayish brown (10YR 4/2) moist; moderate coarse and medium subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; common fine and very fine roots; many fine interstitial and common fine tubular pores; 50 percent distinct pressure faces; slightly alkaline (pH 7.4). (7 to 100 cm thick)

BC--73 to 152 cm; yellowish brown (10YR 5/4) loam, brown (10YR 4/3) moist; moderate coarse subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common very fine roots; common fine tubular and many very fine interstitial pores; slightly alkaline (pH 7.6).

TYPE LOCATION: Malheur County, Oregon; approximately 1.2 miles SE of Arock, Oregon; 457850 UTM easting, 4748057 UTM northing, zone 11 NAD83 on the USGS Arock 7.5 minute quad, latitude 42 degrees, 53 minutes, 2 seconds north and longitude 117 degrees, 30 minutes, 58 seconds west NAD83.

RANGE IN CHARACTERISTICS:

Soil Moisture - The soil moisture control section is dry throughout in late summer and fall and moist in winter and spring; aridic moisture regime that borders on xeric.

Soil temperature - Mean annual temperature is 8 to 9 degrees C.

Mollic epipedon thickness - 25 to 50 cm, includes the upper part of the argillic horizon.

Other Features - Relict redoximorphic features are present throughout the profile in some pedons.

Control section - Clay content - 20 to 35 percent.
Rock fragments - 0 to 25 percent, mainly gravel.

A horizon -
Value: 5 or 6 dry and 2 to 4 moist.
Chroma: 2 or 3 dry or moist.
Reaction: neutral through moderately alkaline.
Volcanic glass: Volcanic glass is estimated to range from 30 to 50 percent of the 0.02 to 2 mm fraction.

Bt horizons -
Value: 3 to 6 dry and 2 to 4 moist.
Chroma: 1 to 6 dry or moist.
Texture: Ashy silty clay loam, clay loam. Thin subhorizons of clay are in some pedons.
Clay content: Averages 27 to 35 percent.
Rock fragments: 0 to 25 percent, mainly gravel and cobbles.
Reaction: Slightly alkaline through moderately alkaline.
Volcanic glass: Volcanic glass is estimated to range from 5 to 30 percent of the 0.02 to 2 mm fraction.

BC horizon -
Value: 5 to 7 dry and 3 to 5 moist.
Chroma: 3 or 4 dry and 2 to 4 moist.
Texture: Clay loam, silty clay loam, loam.
Clay content: 25 to 35 percent.
Rock fragments: 0 to 25 percent, mainly gravel.
Reaction: Slightly alkaline through moderately alkaline.

COMPETING SERIES: These are the Meadowridge (OR), Lequerica (OR), and Toler (WA) soils. The Meadowridge soils have Bk horizons at depths of 64 to 112 cm and have 5 to 20 percent glass in the A horizon. The Lequerica soils have 20 to 80 percent durinodes. The Toler soils are 50 to 100 cm to hard bedrock.

GEOGRAPHIC SETTING: Wisher soils are on stream terraces. These soils formed in volcanic ash and loess over old mixed alluvium. Slopes are 0 to 6 percent. Elevations are 1,170 to 1,185 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 280 mm; mean annual temperature is 7 to 8 degrees C, and the frost-free period is 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bogusrim, Clarksbutte, Goose Creek, Silverash, Sheepsprings, and the competing Lequerica soils. Bogusrim and Clarksbutte soils are 50 to 100 cm to a duripan. Goose Creek series has a mollic epipedon greater than 25 cm thick. Silverash and Sheepsrings soils are poorly drained.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, medium runoff, slow and very slow permeability, moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Cropland, rangeland, and wildlife habitat. The present vegetation is barley. Non-farmed areas have Wyoming big sagebrush, basin wildrye, and Sandberg's bluegrass vegetation.

DISTRIBUTION AND EXTENT: Southeast Oregon; the soil is of moderate extent. MLRA 25.

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

SERIES PROPOSED: Malheur County, Oregon, Southern Part, 2008.

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

Mollic Epipedon - The zone from the soil surface to about 25 cm (A and Bt1 horizons).

Argillic horizon - The zone from about 12 to 73 cm (Bt1 and Bt2 horizons).

Vitritorrandic feature - Aridic moisture regime bordering on Xeric. Volcanic glass is 30 to 50 percent of the 0.02 to 2 mm fraction in the zone from 0 to 12 cm (Ap horizon). Volcanic glass is 5 to 30 percent of the 0.02 to 2 mm fraction in the zone from 12 to 73 cm (Bt horizons).

Particle-size control section - The zone from 12 to 73 cm (Bt1 and Bt2 horizons).


National Cooperative Soil Survey
U.S.A.