LOCATION BRISBOIS OREstablished Series
TAXONOMIC CLASS: Clayey, smectitic, mesic, shallow Xeric Haplargids
TYPICAL PEDON: Brisbois very cobbly clay loam - rangeland, on a 39 percent slope at an elevation of 2,180 feet. (When described on November 9, 1998, the surface horizon was moist but dry in the lower layers. Colors are for moist soils unless otherwise noted.)
A--0 to 3 inches; brown (10YR 4/3) very cobbly clay loam, pale brown (10YR 6/3) dry; weak medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine and common very fine roots; few fine and common very fine tubular pores; slightly effervescent; 30 percent cobbles and 20 percent gravel; moderately alkaline (pH 8.4); abrupt wavy boundary. (1 to 4 inches thick)
2Btk--3 to 9 inches; dark grayish brown (10YR 4/2) clay; dark grayish brown (10YR 4/2) dry; strong medium prismatic structure; very hard, very firm, very sticky and very plastic; few fine and very fine roots; few fine and very fine tubular pores; continuous distinct clay films on ped faces and in pores; few medium masses of lime; strongly effervescent; 10 percent gravel; moderately alkaline (pH 8.4); abrupt wavy boundary. (3 to 7 inches thick)
3Cr--9 to 19 inches; weathered volcanic tuff; brown (10YR 5/3) dry (75 percent) and very pale brown (10YR 8/3) dry (25 percent).
TYPE LOCATION: Grant County, Oregon, located NW of the Blue Basin Area of the John Day Fossil Beds (Sheep Rock Unit) about 11 miles south of Kimberly, Oregon; 1,400 feet north and 1,100 feet east of the SW corner of section 20, T. 11 S., R. 26 E. Latitude 44 degrees, 35 minutes, 38 seconds North; Longitude 119 degrees, 37 minutes, 44 seconds West.
RANGE IN CHARACTERISTICS: The soil moisture control section is dry in all parts for one-half to three-fourths of the time when the soil temperature is above 41 degrees F. The mean annual soil temperature is 47 to 53 degrees F. Depth to a paralithic contact is 4 to 10 inches. Depth to an argillic horizon is 1 to 4 inches.
The A horizon has value of 4 or 5 moist, 6 or 7 dry, and chroma of 2 or 3 moist and dry. It is clay loam with 27 to 35 percent clay. It has 0 to 20 percent stones, 10 to 30 percent cobbles, and 15 to 25 percent gravel.
The 2Btk horizon has hue of 10YR or 2.5Y, value of 4 or 5 moist, 4 to 6 dry, and chroma of 2 to 4 moist and dry. It is clay with 45 to 60 percent clay. It has 0 to 15 percent gravel. Paragravels range from 0 to 20 percent and paracobbles from 0 to 15 percent. Carbonates occurs as coatings on rock fragments or as masses.
COMPETING SERIES: These are the Bedzee, Chalco, Espint, Gumble, and Xman series. Bedzee soils are shallow to a paralithic contact of shale and have 15 to 35 percent rock fragments in the argillic horizon. Chalco soils are shallow to weathered tuff and lacks secondary carbonates in the argillic horizon. Espint soils lacks secondary carbonates in the argillic horizon, are moist 10 to 20 days during the summer, and have a soil temperature of 53 to 59 degrees F. Gumble soils are 14 to 20 inches to fractured, soft tuff and have more than 15 percent fine sand or coarser in the sand-size fraction of the control section. Xman soils are shallow to weathered andesite and have hard bedrock at depths of 20 to 40 inches.
GEOGRAPHIC SETTING: Brisbois soils are on hillslopes. This soil formed in weathered John Day volcanic tuff overlain by clayey sediments. A mantle of basaltic colluvium and loess was added later. Slope is 2 to 90 percent. Elevation is 2,000 to 3,800 feet. The climate is semi-arid with cool, moist winters and hot, dry summers. The mean annual precipitation is 9 to 12 inches, and the mean annual temperature is 48 to 52 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cant, Drinkwater, Gooserock, Meadowridge, and Monroe soils. Cant soils are clayey-skeletal, moderately deep to bedrock, and are on south facing slopes. Drinkwater soils are loamy-skeletal, very deep to bedrock, and are on colluvial footslopes and fans. Gooserock soils are loamy-skeletal, have Vitrandic properties in the soil surface, are very deep to bedrock, and are on north slopes. Meadowridge soils are fine-loamy, very deep to bedrock, and are on benches. Monroe soils are fine-loamy, very deep to bedrock, and are on flood plains and very gentle alluvial fans.
DRAINAGE AND PERMEABILITY: Well drained; very slow permeability.
USE AND VEGETATION: Used for livestock grazing and wildlife habitat. The potential native vegetation is bluebunch wheatgrass, Sandberg bluegrass, bottlebrush squirreltail, shadscale, and broom snakeweed.
DISTRIBUTION AND EXTENT: East-central Oregon, B-10. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: John Day Fossil Beds National Monument, Oregon, 2000.
REMARKS: Diagnostic horizon and features recognized in this pedon are:
Ochric epipedon
Argillic horizon - 3 to 9 inches averages 10 percent rock fragments and 50 percent clay.
Particle size control section - 0 to 9 inches averages 23 percent rock fragments and 43 percent clay.
ADDITIONAL DATA: Partial laboratory data is available for this soil. Reference sample S98OR-023-005-(1-5) from Grant County, Oregon.