LOCATION EXFO                    OR

Established Series
Rev. SCW/TDT
02/2025

EXFO SERIES

Landscape--foothills, canyonlands, plateaus
Landform--canyons, hillslopes, structural benches
Slope--2 to 90 percent
Parent material--colluvium derived from exfoliated Picture Gorge Basalts
Mean annual precipitation--about 300 mm
Mean annual air temperature--about 10 degrees C
Depth class--very shallow
Drainage class--somewhat excessively drained
Soil moisture regime--aridic (torric)
Soil temperature regime--mesic
Soil moisture subclass--typic

TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Lithic Torriorthents

TYPICAL PEDON: Exfo very gravelly loamy coarse sand, rangeland, on a 50 percent slope at an elevation of 700 meters (When described on September 13, 1999, the soil was dry throughout.)

A--0 to 13 cm; brown (10YR 5/3) very gravelly loamy coarse sand, dark brown (10YR 3/3) moist; single grain; loose, nonsticky and nonplastic; few very fine roots; few very fine irregular pores; 20 percent cobbles, 15 percent coarse gravels, and 15 percent fine gravel; moderately alkaline (pH 8.1); abrupt wavy boundary.

R--13 cm; dark colored, exfoliated basalt

TYPE LOCATION: Grant County, Oregon, located about 6 km north of the junction of Highways 19 and 26 near Squaw Creek or 24 km south of the community of Kimberly; 460 meters east and 490 meters north of the SW corner of section 30, T. 11 S., R. 26 E; latitude 44.5823402 degrees north, longitude 119.6480255 degrees west; WGS84; coordinates estimated from PLSS description

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--8 to 12 degrees C
Soil moisture--dry in all parts for more than three-fourths of the time when the soil temperature is 5 degrees C or more
Depth to lithic bedrock--3 to 20 cm, typically 10 to 15 cm

A horizon
*Hue--10YR
*Value--2 or 3 moist, 4 or 5 dry
*Chroma--2 to 4 moist and dry
*Fine earth texture--loamy coarse sand
*Clay--5 to 10 percent
*Sand--80 to 90 percent
*Total fragments--35 to 70 percent
*Fine gravel (2.0-5.0mm)--15 to 35 percent
*Medium and coarse gravel--5 to 35 percent
*Cobbles--10 to 20 percent
*Organic matter--0.5 to 1.0 percent
*Reaction--slightly to moderately alkaline
*Thickness--3 to 20 cm

COMPETING SERIES:
Jacaranda--formed in lacustrine deposits; annual precipitation is about 125mm

GEOGRAPHIC SETTING:
Elevation--425 to 1460 meters
Climate--semi-arid with cool, moist winters and hot, dry summers
Mean annual precipitation--230 to 400 mm
Mean annual air temperature--7 to 11 degrees C
Frost-free period--90 to 140 days
Lithology--Miocene Picture Gorge Basalt

GEOGRAPHICALLY ASSOCIATED SOILS:
Brisbois--on steep slopes near Badlands; clayey family; formed over weathered tuff
Drinkwater--loamy-skeletal family; very deep to bedrock; located on south slopes
Gooserock--loamy-skeletal family; very deep to bedrock; located on north slopes
Haystack--loamy-skeletal family; very deep to bedrock; located on alluvial fans
Lickskillet--located on south slopes; mollic epipedon; 30 to 50 cm to bedrock
Ninetysix--loamy-skeletal family; very deep to bedrock

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--somewhat excessively drained
Saturated in normal years--none
Flooding--none
Ponding--none
Saturated hydraulic conductivity--high to very high

USE AND VEGETATION:
Use--livestock grazing, wildlife habitat
Potential natural vegetation--bluebunch wheatgrass, purple sage, curl leaf mountain mahogany

DISTRIBUTION AND EXTENT:
Distribution--East-central Oregon; MLRA 10
Extent--moderately extensive

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: John Day Fossil Beds National Monument, Oregon, 2000.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
*Ochric epipedon--0 to 13 cm
*Particle size control section--0 to 13 cm

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National Cooperative Soil Survey
U.S.A.