LOCATION RUFUS                   WA

Established Series
Rev. NCD-BDG-RJS
05/2017

RUFUS SERIES


The Rufus series consists of shallow, well drained soils formed in colluvium over residuum derived from metasedimentary bedrock, and modified by till, volcanic ash and/or loess. These soils are mostly on glaciated hillsides, mountainsides and ridgetops. Slopes are 8 to 65 percent. Average annual precipitation is about 610 mm, and the mean annual air temperature is about 8.3 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Lithic Ultic Haploxerolls

TYPICAL PEDON: Rufus channery ashy loam - woodland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 10 cm; grayish brown (10YR 5/2) channery ashy loam, very dark grayish brown (10YR 3/2) moist; weak, fine and medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium roots; many fine pores; 30 percent channers; neutral (pH 6.8); clear wavy boundary. (8 to 15 cm thick)

A2--10 to 20 cm; brown (10YR 5/3) very flaggy ashy loam, dark brown (10YR 3/3) moist; weak, fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine, medium, and coarse roots; many fine pores; 25 percent channers and 25 percent flagstones; neutral (pH 6.6); abrupt irregular boundary. (8 to 20 cm thick)

AC--20 to 35 cm; grayish brown (10YR 5/2) extremely flaggy ashy loam, dark brown (10YR 3/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; 25 percent channers and 40 percent flagstones; slightly acid (pH 6.4); abrupt irregular boundary. (0 to 20 cm thick)

2R--35 cm; phyllite bedrock.

TYPE LOCATION: Stevens County, Washington; 3.2 kilometers south of Gifford and 4.4 kilometers south and east of the Columbia River in Deer Creek drainage; 365 meters east and 610 meters north of the southwest corner of section 7, T. 32 N., R. 38 E.

RANGE IN CHARACTERISTICS:
Depth to a lithic contact -- 25 to 50 cm
Moisture regime -- Xeric
Note: These soils are usually moist in all horizons, but are dry in all parts from 20 cm to a lithic contact for 75 to 90 consecutive days following summer solstice.
Mean annual soil temperature is 8.9 to 10.0 degrees C.
Temperature regime - frigid

Control Section rock fragments -- averages 35 to 80 percent

Volcanic ash influenced layer
Volcanic glass -- 5 to 20 percent volcanic glass
Acid-oxalate extractable Al plus 1/2 acid-oxalate extractable Fe -- 0.4 to 1.0 percent
15-bar water retention -- less than 12 percent for air dried samples.

A1 horizon
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3 dry and moist.
Texture (less than 2mm fraction): ashy loam or ashy sandy loam.
Clay Content: 8 to 15 percent
Rock fragments: 15 to 35 percent--15 to 35 percent channers; 0 to 5 percent flagstones
Reaction: pH 6.1 to 7.3

A2 horizon
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3 dry or moist
Texture (less than 2mm fraction): ashy loam or ashy sandy loam
Clay content: 8 to 15 percent
Rock fragments: 35 to 70 percent--25 to 50 percent channers; 5 to 40 percent flagstones
Reaction: pH 6.1 to 7.3

AC horizon
Hue: 10YR or 2.5Y dry or moist
Value: 5 or 6 dry; 3 to 5 moist
Chroma: 2 or 3 dry and moist
Texture (less than 2mm fraction): loam or sandy loam
Rock fragments: 40 to 80 percent--20 to 50 percent channers; 5 to 40 percent flagstones
Reaction: pH 6.1 to 7.3

Bw horizon (where present)
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture (less than 2mm fraction): ashy loam or ashy sandy loam
Rock Fragments: 40 to 80 percent--35 to 50 percent channers and 5 to 40 percent flagstones
Reaction: pH 6.1 to 7.3

COMPETING SERIES:
Cassyhill (ID): are dry for 60 to 75 consecutive days from mid-July to September
Oakside (CA): do not have volcanic glass in the surface and have a mean annual soil temperature of 10 to 15 degrees C.

GEOGRAPHIC SETTING: Rufus soils are on glaciated hillsides, mountainsides, and ridgetops at elevations of 485 to 1,480 meters. Aspect is usually south-facing. Slopes are convex or complex and range from 8 to 65 percent. These soils formed in colluvium over residuum derived from metasedimentary bedrock, and modified by till, volcanic ash and/or loess. These soils are in a continental climate with warm, dry summers and cool, moist winters. Average annual precipitation is 375 to 760 mm. The mean annual temperature is 7.0 to 11.0 degrees C. The frost-free season ranges from 90 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aits, Dehart, Huckleberry, Maki, Oxerine, Raisio, Scoap, and Stevens soils. Aits, Dehart, Scoap, and Stevens soils are more than 150 cm deep. Aits soils are on glaciated mountains. Dehart soils are on mountains. Scoap soils are frigid and are on uplands and mountainsides. Huckleberry soils are ashy over loamy-skeletal, are cryic and are on mountains. Maki, Oxerine, and Raisio soils are 50 to 100 cm deep to a lithic contact. Maki soils are on south facing glaciated uplands and mountainsides. Stevens soils are coarse-loamy and are on south facing hillsides, rounded hilltops, mountainsides and ridgetops.

DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; moderate permeability.

USE AND VEGETATION: Native vegetation is widely spaced ponderosa pine and scattered Douglas-fir with an understory of Saskatoon serviceberry, ceanothus, Idaho fescue, bluebunch wheatgrass, pinegrass, prairie junegrass, arrowleaf balsamroot, lupine, eriogonum, phlox and stonecrop.

DISTRIBUTION AND EXTENT: Northeastern Washington. Series is moderately extensive. MLRA 43A, 6.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Stevens County, Washington, 1978.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon -- 0 to 35 cm (A1, A2, AC horizons)
Lithic contact -- at 35 cm (R horizon).
Particle-size control section -- 0 to 35 cm (A1, A2, AC horizons)

Taxonomic version: Keys to Soil Taxonomy, Twelfth Edition, 2014.


National Cooperative Soil Survey
U.S.A.