LOCATION MAHOGEE                 NV

Established Series
Rev. PWB-TM-JVC-JBF
07/2019

MAHOGEE SERIES

The Mahogee series consists of shallow, well drained soils that formed in residuum and colluvium derived from rhyolite. Mahogee soils are on mountains. Slopes are 15 to 75 percent. The mean annual precipitation is about 430 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy, mixed, superactive Lithic Argicryolls

TYPICAL PEDON: Mahogee gravelly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered by 30 percent gravel.

A--0 to 5 cm; dark gray (10YR 4/1) gravelly sandy loam, black (10YR 2/1) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine interstitial pores; 15 percent gravel; neutral (pH 6.6); abrupt smooth boundary. (5 to 10 cm thick)

Bt1--5 to 13 cm; grayish brown (10YR 5/2) gravelly coarse sandy loam, very dark gray (10YR 3/1) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, fine, and few medium roots; many very fine tubular pores; few faint clay films coating and bridging sand grains; 15 percent gravel; neutral (pH 6.8); abrupt smooth boundary. (8 to 13 cm thick)

Bt2--13 to 43 cm; grayish brown (10YR 5/2) gravelly coarse sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine, common fine, common medium, and few coarse roots; many very fine and few fine tubular pores; few faint clay films coating and bridging sand grains; 30 percent gravel; neutral (pH 7.0); abrupt wavy boundary. (20 to 36 cm thick)

R--43 cm; rhyolite bedrock.

TYPE LOCATION: Elko County, Nevada; on the Humboldt National Forest about 4.5 miles northeast of Merritt Mountain in The Mahoganies; about 600 feet north and 1,800 feet east of the southwest corner of section 10, T. 46 N., R. 55 E.; USGS Hicks Mountain 7.5 minute topographic quadrangle; latitude 41 degrees 53 minutes 03 seconds N and longitude 115 degrees 45 minutes 28 seconds W; NAD 83. WGS84 Decimal Degrees 41.8841667 latitude, -115.7577778 longitude

RANGE IN CHARACTERISTICS:
Soil moisture: Moist during late fall through spring, usually dry in summer through mid-fall; Moist in all parts for more than 120 days following the winter solstice; xeric soil moisture regime.
Mean annual soil temperature: 5 to 7 degrees C.
Mean summer soil temperature: 12 to 14 degrees C.
Mollic epipedon thickness: 36 to 50 cm, includes the Bt1 and Bt2 horizons.
Depth to bedrock: 36 to 50 cm to a lithic contact.

Particle-size control section - Clay content: 18 to 25 percent.
Rock fragments: 15 to 35 percent, mainly fine (2 to 5 mm diameter) gravel. Lithology of fragments are rhyolite.

A horizon
Value 4 or 5 dry, 2 or 3 moist.
Chroma: 1 or 2, dry or moist.
Organic matter content: 2 or 3 percent.

Bt horizons
Value 4 or 5 dry, 2 or 3 moist.
Texture: Gravelly coarse sandy loam or gravelly sandy clay loam.
Structure: Weak or moderate medium or coarse subangular blocky.
Organic matter content: 1 or 2 percent.

COMPETING SERIES: These are the Carbol, Chittum, Gilispie, and Katseanes series.

Carbol and Gilispie soils have an ustic moisture regime. Chittum soils have hue of 2.5YR or 5YR in the argillic horizon. Katseanes soils have 0 to 10 percent rock fragments in the particle-size control section and have mollic epipedons that are 25 to 33 cm thick.

GEOGRAPHIC SETTING: Mahogee soils are on mountains. They typically occur on shoulder and backslope positions. These soils formed in residuum and colluvium derived from rhyolite. Slopes are 15 to 75 percent. Elevations range from 1,985 to 2,445 meters. The climate is semiarid with cold, moist winters and cool, dry summers. The mean annual precipitation is 400 to 460 mm, mean annual temperature is 4 to 6 degrees C, and the frost-free period is 60 to 75 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Keman and Tweener soils. Keman soils are loamy-skeletal, very deep, and have thick mollic epipedons. Tweener soils are loamy-skeletal, very shallow and shallow to lithic contacts, and have a frigid temperature regime.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very high surface runoff; moderate permeability; moderatelyhigh saturated hydraulic conductivity.

USE AND VEGETATION: Mahogee soils are used for rangeland and wildlife habitat. The present vegetation is mainly curlleaf mountainmahogany, mountain big sagebrush, snowberry, bluebunch wheatgrass, and Idaho fescue.

DISTRIBUTION AND EXTENT: Northeastern Nevada. These soils are not extensive. MLRA 25.

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

SERIES ESTABLISHED: Elko County (Humboldt National Forest), Nevada, 2017. The name is coined from a nearby mountain range.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 43 cm (A, Bt1, and Bt2 horizons).
Argillic horizon - The zone from 5 to 43 cm (Bt1 and Bt2 horizons).
Lithic contact - The boundary at 43 cm to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 5 to 43 cm (Bt1 and Bt2 horizons).

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National Cooperative Soil Survey
U.S.A.