LOCATION BLACK RIDGE        UT
Established Series
Rev. MEO-AJE-MJD
04/2004

BLACK RIDGE SERIES


The Black Ridge series consist of shallow to a hardpan, well drained soils that formed in colluvium and residuum from basalt. The Black Ridge soils are on lava plains and lava flows. Slope ranges from 6 to 30 percent. The mean annual precipitation is about 13 inches and the mean annual temperature is about 47 degrees F.

TAXONOMIC CLASS: Clayey, smectitic, mesic, shallow Petrocalcidic Palexerolls

TYPICAL PEDON: Black Ridge very cobbly silt loam, range. (Colors are for dry soils unless otherwise noted.)

A--0 to 3 inches; dark grayish brown (10YR 4/2) very cobbly silt loam, very dark brown (10YR 2/2) moist; weak thick platy structure that parts to weak fine granules; slightly hard, friable, slightly sticky, slightly plastic; few fine roots; common medium vesicular pores; noneffervescent; neutral (pH 6.7); clear smooth boundary. (3 to 5 inches thick)

Bt1--3 to 7 inches; brown (7.5YR 4/2) silty clay loam, very dark brown (7.5YR 2/2) moist; weak medium prismatic structure that parts to weak fine subangular blocky structure; hard, firm, very sticky, plastic; few medium and fine roots; thin continuous clay films on faces of peds; noneffervescent; slightly acid (pH 6.1); clear smooth boundary. (0 to 4 inches thick)

Bt2--7 to 14 inches; brown (7.5YR 5/4) clay, brown (7.5YR 4/2) crushed and brown (7.5YR 4/3) in aggregate, moist; strong medium prismatic structure that parts to strong medium angular blocky; very hard, firm, very sticky, very plastic; common medium, few fine and coarse roots; common medium pores; thick continuous clay films on faces of peds; noneffervescent; neutral (pH 6.7); clear irregular boundary. (5 to 11 inches thick)

Bk--14 to 15 inches; brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; hard, friable, sticky, plastic; noneffervescent matrix with many soft lime nodules up to 1/4 inch in diameter; slightly alkaline (pH 7.4); clear wavy boundary. (1 to 4 inches thick)

Bkm1--15 to 16 inches; very pale brown (10YR 8/3) loam, very pale brown (10YR 7/3) moist; massive; very strongly calcareous; strongly cemented horizon of lime accumulation; slightly alkaline (pH 7.5); abrupt wavy boundary. (1 to 4 inches thick)

Bkm2--16 to 18 inches; indurated lime cemented hardpan; abrupt wavy boundary. (0 to 2 inches thick)

Bkm3--18 to 36 inches; strongly cemented lime pan otherwise similar to the Bkm2 horizon; abrupt wavy boundary. (10 to 18 inches thick)

R--36 inches; basalt bedrock.

TYPE LOCATION: Beaver County, Utah; 1 1/2 miles north of Cowboy Spring, 1/8 mile west of road; 1/4 mile north and 1/2 mile west of the southwest 1/4 of section 36, T.26S., R.8W; lat. 38 degrees 25 minutes 13.02 seconds N. and long. 112 degrees 43 minutes 41.78 W., NAD 83.

RANGE IN CHARACTERISTICS: Depth to the calcium carbonate cemented hardpan ranges from 14 to 20 inches. Depth to the basalt bedrock ranges from 30 to 40 inches. Rock fragments occur principally as a surface mantle.

The mean annual soil temperature ranges from 47 degrees to 50 degrees F. The soil moisture regime is aridic bordering on xeric.

The A horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3. It has weak, moderately thick to thin platy structure that parts to weak or moderate fine granular structure. This horizon is slightly hard or hard. It ranges from slightly acid to slightly alkaline.

The Bt horizon has hue of 10YR or 7.5YR, value of 4 through 6 dry, 3 through 5 moist, and chroma of 2 through 4. The upper part is darker than 3.5 moist and 5.5 dry to a depth of over 7 inches below the soil surface but less than 18 inches. This horizon is clay loam, clay or silty clay containing over 35 percent clay. It has moderate or strong prismatic parting to moderate or strong angular blocky structure. The Bt horizon is hard or very hard and firm or very firm.

COMPETING SERIES: These are no competing series.

GEOGRAPHIC SETTING: Black Ridge soils are on rolling to steep lava plains and lava flows of basalt at elevations of 6,000 to 6,800 feet. Slope ranges from 6 to 30 percent. Mean annual temperature is about 45 degrees to 48 degrees F., mean summer temperature is about 64 degrees to 66 degrees F. The average annual precipitation ranges from about 12 to 14 inches. The frost-free period ranges from 100 to 108 days.

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Phage soil. Phage soils are gravelly and very gravelly soils that lack petrocalcic and Bt horizons.

DRAINAGE AND PERMEABILITY: Well-drained; high runoff; slow permeability.

USE AND VEGETATION: Used for range, wildlife, and limited grazing. The present vegetation is black sagebrush, juniper, Wyoming big sagebrush, antelope bitterbrush, cliffrose, and bluebunch wheatgrass.

DISTRIBUTION AND EXTENT: Basalt areas in northeast Beaver County. These soils are not extensive. MLRA 28A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Beaver County, (Beaver-Cove Fort Area), Utah, 1971.

REMARKS: Diagnostic horizons and features in this pedon include:
Mollic epipedon - from a depth of 0 to 7 inches (A and Bt1 horizons).
Argillic horizon - from a depth of 7 to 14 inches (Bt2 horizon).
Petrocalcic horizon - from a depth of 15 to 36 inches (Bkm1, Bkm2 and Bkm3 horizons).


National Cooperative Soil Survey
U.S.A.