LOCATION DEKOOM                  NV

Established Series
Rev. TEB/RLB/JBF
02/2016

DEKOOM SERIES

The Dekoom series consists of very deep, well drained soils that formed in residuum derived from limestone, dolomite, and calcareous shale. Dekoom soils are on side slopes of mountains. Slopes are 30 to 75 percent. The mean annual precipitation is about 360 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic Typic Cryrendolls

TYPICAL PEDON: Dekoom very gravelly loam--rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; brown (10YR 4/3) very gravelly loam, very dark grayish brown (10YR 3/2) moist; weak very thin platy structure; soft, very friable, slightly sticky and slightly plastic; many very fine and common fine roots; few very fine vesicular pores; 35 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (5 to 13 cm thick)

A2--8 to 33 cm; brown (10YR 4/3) gravelly silt loam, very dark grayish brown (10YR 3/2) moist; weak very thin platy structure; soft, very friable, slightly sticky and slightly plastic; many very fine and common fine, medium, and coarse roots; common very fine tubular pores; 30 percent gravel; thin carbonate coatings on undersides of gravel; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary (13 to 25 cm thick)

Bk1--33 to 53 cm; pale brown (10YR 6/3) very gravelly loam, brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; many very fine and few fine and medium roots; few very fine tubular pores; 50 percent gravel; few fine soft masses of carbonate and thin carbonate coatings on all sides of gravel; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (13 to 25 cm thick)

Bk2--53 to 94 cm; pale brown (10YR 6/3) very gravelly loam, brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine, fine, and medium roots; few very fine tubular pores; 55 percent gravel; few soft masses and thin carbonate coatings on all sides of gravel; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (25 to 40 cm thick)

C--94 to 152 cm; pale brown (10YR 6/3) extremely gravelly loam, brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; 70 percent gravel; strongly effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Pershing County, Nevada; near Star Peak, approximately 10 miles south of Imlay, about 1,600 feet south and 900 feet west of the northeast corner of section 29, T. 31 N., R. 34 E.; USGS Star Peak 7.5 minute topographic quadrangle; latitude 40 degrees 31 minutes 59 seconds N and longitude 118 degrees 10 minutes 41 seconds W; WGS84 Decimal Degrees 40.5330556 latitude, -118.1780556 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist late fall through early summer, dry late July through September; xeric soil moisture regime.
Mean annual soil temperature: 6 to 8 degrees C.
Average summer soil temperature: 12 to 15 degrees C.
Mollic epipedon thickness: 25 to 38 cm. Does not include the Bk horizons.
Thickness of A and Bk horizons: 50 to 100 cm.
Carbonates: Bk horizon has 1 to 4 percent more than the A horizons.
Carbonate equivalent: 40 to 60 percent.
Reaction: Moderately alkaline or strongly alkaline

Particle-size control section - Clay content: 10 to 18 percent.
Rock fragments: 40 to 60 percent, mainly gravel.

A horizon
Value: 4 or 5 dry.
Chroma: 2 or 3.
Structure: Platy or granular.

Bk horizon
Value: 4 through 6 dry, 3 or 4 moist.
Chroma: 3 or 4.
Texture: Very gravelly loam or very gravelly silt loam.
Clay content: 10 to 15 percent.
Rock fragments: 35 to 60 percent, mainly gravel.

C horizon
Value: 4 through 6 dry, 4 or 5 moist.
Chroma: 3 or 4.
Rock fragments: 50 to 75 percent, mainly gravel.

COMPETING SERIES: These are the Hatur and Redmanson series.

Hatur soils have bedrock within depths of 50 to 100 cm, 60 to 80 percent rock fragments in the particle-size control section, and a carbonate equivalent of 60 to 80 percent. Redmanson soils have a particle-size control section with a fine earth fraction that is typically silty clay loam or silt loam with 18 to 35 percent clay.

GEOGRAPHIC SETTING: Dekoom soils are on side slopes of mountains. These soils formed in residuum derived from limestone, dolomite, sandstone, chert and calcareous shale. Slopes are 30 to 75 percent. Elevations are 2,290 to 2,750 meters. The climate is cool, semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 360 to 410 mm, mean annual temperature is 4 to 7 degrees C, and the frost-free season is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the tentative Hummer and Pflum series. Hummer soils are moderately deep and have a carbonate equivalent of 20 to 35 percent. Pflum soils have a mollic epipedon 40 to 76 cm thick and a carbonate equivalent of 15 to 35 percent.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, rapid runoff; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly low sagebrush, spike fescue, Nevada bluegrass, Cusick bluegrass, bluebunch cheatgrass, and lupine.

DISTRIBUTION AND EXTENT: North-central Nevada. These soils are not extensive. MLRA 24.

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

SERIES ESTABLISHED: Pershing County, Nevada, East Part, 1986.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 33 cm (A1 and A2 horizons).
Particle-size control section - The zone from 25 to 100 cm (Bk1, Bk2 and part of the A2 and C horizons).

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National Cooperative Soil Survey
U.S.A.